Programs & Examples On #Managed directx

Tools and techniques to use DirectX through managed code. Managed DirectX is also known as MDX.

How to loop through elements of forms with JavaScript?

You can use getElementsByTagName function, it returns a HTMLCollection of elements with the given tag name.

var elements = document.getElementsByTagName("input")
for (var i = 0; i < elements.length; i++) {
    if(elements[i].value == "") {
        alert('empty');
        //Do something here
    }
}

DEMO

You can also use document.myform.getElementsByTagName provided you have given a name to yoy form

DEMO with form Name

ExecuteNonQuery doesn't return results

If what you want is to get just a single integer from the query, use:

myCmdObject.ExecuteScalar()

Center icon in a div - horizontally and vertically

Here is a way to center content both vertically and horizontally in any situation, which is useful when you do not know the width or height or both:

CSS

#container {
    display: table;
    width: 300px; /* not required, just for example */
    height: 400px; /* not required, just for example */
}

#update {
    display: table-cell;
    vertical-align: middle;
    text-align: center;
}

HTML

<div id="container">
    <a id="update" href="#">
        <i class="icon-refresh"></i>
    </a>
</div>

JSFiddle

Note that the width and height values are just for demonstration here, you can change them to anything you want (or remove them entirely) and it will still work because the vertical centering here is a product of the way the table-cell display property works.

Is it possible to cast a Stream in Java 8?

Late to the party, but I think it is a useful answer.

flatMap would be the shortest way to do it.

Stream.of(objects).flatMap(o->(o instanceof Client)?Stream.of((Client)o):Stream.empty())

If o is a Client then create a Stream with a single element, otherwise use the empty stream. These streams will then be flattened into a Stream<Client>.

how to check redis instance version?

To support the answers given above, The details of the redis instance can be obtained by

$ redis-cli
$ INFO

This gives all the info you may need

# Server
redis_version:5.0.5
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:da75abdfe06a50f8
redis_mode:standalone
os:Linux 5.3.0-51-generic x86_64
arch_bits:64
multiplexing_api:epoll
atomicvar_api:atomic-builtin
gcc_version:7.5.0
process_id:14126
run_id:adfaeec5683d7381a2a175a2111f6159b6342830
tcp_port:6379
uptime_in_seconds:16860
uptime_in_days:0
hz:10
configured_hz:10
lru_clock:15766886
executable:/tmp/redis-5.0.5/src/redis-server
config_file:

# Clients
connected_clients:22
....More Verbose

The version lies in the second line :)

Reverse colormap in matplotlib

The solution is pretty straightforward. Suppose you want to use the "autumn" colormap scheme. The standard version:

cmap = matplotlib.cm.autumn

To reverse the colormap color spectrum, use get_cmap() function and append '_r' to the colormap title like this:

cmap_reversed = matplotlib.cm.get_cmap('autumn_r')

pthread function from a class

Too many times I've found ways to solve what you are asking for that, in my opinion are too complicated. For instance you have to define new class types, link library etc. So I decided to write a few lines of code that allow the end user to basically be able to "thread-ize" a "void ::method(void)" of whatever class. For sure this solution I implemented can be extended, improved etc, so, if you need more specific methods or features, add them and please be so kind to keep me in the loop.

Here are 3 files that show what I did.

    // A basic mutex class, I called this file Mutex.h
#ifndef MUTEXCONDITION_H_
#define MUTEXCONDITION_H_

#include <pthread.h>
#include <stdio.h>

class MutexCondition
{
private:
    bool init() {
        //printf("MutexCondition::init called\n");
        pthread_mutex_init(&m_mut, NULL);
        pthread_cond_init(&m_con, NULL);
        return true;
    }

    bool destroy() {
        pthread_mutex_destroy(&m_mut);
        pthread_cond_destroy(&m_con);
        return true;
    }

public:
    pthread_mutex_t m_mut;
    pthread_cond_t m_con;

    MutexCondition() {
        init();
    }
    virtual ~MutexCondition() {
        destroy();
    }

    bool lock() {
        pthread_mutex_lock(&m_mut);
        return true;
    }

    bool unlock() {
        pthread_mutex_unlock(&m_mut);
        return true;
    }

    bool wait() {
        lock();
        pthread_cond_wait(&m_con, &m_mut);
        unlock();
        return true;
    }

    bool signal() {
        pthread_cond_signal(&m_con);
        return true;
    }
};
#endif
// End of Mutex.h

// The class that incapsulates all the work to thread-ize a method (test.h):

#ifndef __THREAD_HANDLER___
#define __THREAD_HANDLER___

#include <pthread.h>
#include <vector>
#include <iostream>
#include "Mutex.h"

using namespace std;

template <class T> 
class CThreadInfo
{
  public:
    typedef void (T::*MHT_PTR) (void);
    vector<MHT_PTR> _threaded_methods;
    vector<bool> _status_flags;
    T *_data;
    MutexCondition _mutex;
    int _idx;
    bool _status;

    CThreadInfo(T* p1):_data(p1), _idx(0) {}
    void setThreadedMethods(vector<MHT_PTR> & pThreadedMethods)
    {
        _threaded_methods = pThreadedMethods;
      _status_flags.resize(_threaded_methods.size(), false);
    }
};

template <class T> 
class CSThread {
  protected:
    typedef void (T::*MHT_PTR) (void);
    vector<MHT_PTR> _threaded_methods;
    vector<string> _thread_labels;
    MHT_PTR _stop_f_pt;
    vector<T*> _elements;
    vector<T*> _performDelete;
    vector<CThreadInfo<T>*> _threadlds;
    vector<pthread_t*> _threads;
    int _totalRunningThreads;

    static void * gencker_(void * pArg)
    {
      CThreadInfo<T>* vArg = (CThreadInfo<T> *) pArg;
      vArg->_mutex.lock();
      int vIndex = vArg->_idx++;
      vArg->_mutex.unlock();

      vArg->_status_flags[vIndex]=true;

      MHT_PTR mhtCalledOne = vArg->_threaded_methods[vIndex];
      (vArg->_data->*mhtCalledOne)();
      vArg->_status_flags[vIndex]=false;
        return NULL;
    }

  public:
    CSThread ():_stop_f_pt(NULL), _totalRunningThreads(0)  {}
    ~CSThread()
    {
      for (int i=_threads.size() -1; i >= 0; --i)
          pthread_detach(*_threads[i]);

      for (int i=_threadlds.size() -1; i >= 0; --i)
        delete _threadlds[i];

      for (int i=_elements.size() -1; i >= 0; --i)
         if (find (_performDelete.begin(), _performDelete.end(), _elements[i]) != _performDelete.end())
              delete _elements[i];
    }
    int  runningThreadsCount(void) {return _totalRunningThreads;}
    int  elementsCount()        {return _elements.size();}
    void addThread (MHT_PTR p, string pLabel="") { _threaded_methods.push_back(p); _thread_labels.push_back(pLabel);}
    void clearThreadedMethods() { _threaded_methods.clear(); }
    void getThreadedMethodsCount() { return _threaded_methods.size(); }
    void addStopMethod(MHT_PTR p)  { _stop_f_pt  = p; }
    string getStatusStr(unsigned int _elementIndex, unsigned int pMethodIndex)
    {
      char ch[99];

      if (getStatus(_elementIndex, pMethodIndex) == true)
        sprintf (ch, "[%s] - TRUE\n", _thread_labels[pMethodIndex].c_str());
      else 
        sprintf (ch, "[%s] - FALSE\n", _thread_labels[pMethodIndex].c_str());

      return ch;
    }
    bool getStatus(unsigned int _elementIndex, unsigned int pMethodIndex)
    {
      if (_elementIndex > _elements.size()) return false;
      return _threadlds[_elementIndex]->_status_flags[pMethodIndex];
    }

    bool run(unsigned int pIdx) 
    {
      T * myElem = _elements[pIdx];
      _threadlds.push_back(new CThreadInfo<T>(myElem));
      _threadlds[_threadlds.size()-1]->setThreadedMethods(_threaded_methods);

      int vStart = _threads.size();
      for (int hhh=0; hhh<_threaded_methods.size(); ++hhh)
          _threads.push_back(new pthread_t);

      for (int currentCount =0; currentCount < _threaded_methods.size(); ++vStart, ++currentCount)
      {
                if (pthread_create(_threads[vStart], NULL, gencker_, (void*) _threadlds[_threadlds.size()-1]) != 0)
        {
                // cout <<"\t\tThread " << currentCount << " creation FAILED for element: " << pIdx << endl;
                    return false;
                }
        else
        {
            ++_totalRunningThreads;
             // cout <<"\t\tThread " << currentCount << " creation SUCCEDED for element: " << pIdx << endl;
                }
      }
      return true;
    }

    bool run() 
    {
            for (int vI = 0; vI < _elements.size(); ++vI) 
            if (run(vI) == false) return false;
          // cout <<"Number of currently running threads: " << _totalRunningThreads << endl;
        return true;
    }

    T * addElement(void)
    {
      int vId=-1;
      return addElement(vId);
    }

    T * addElement(int & pIdx)
    {
      T * myElem = new T();
      _elements.push_back(myElem);
      pIdx = _elements.size()-1;
      _performDelete.push_back(myElem);
      return _elements[pIdx];
    }

    T * addElement(T *pElem)
    {
      int vId=-1;
      return addElement(pElem, vId);
    }

    T * addElement(T *pElem, int & pIdx)
    {
      _elements.push_back(pElem);
      pIdx = _elements.size()-1;
      return pElem;
    }

    T * getElement(int pId) { return _elements[pId]; }

    void stopThread(int i)  
    {
      if (_stop_f_pt != NULL) 
      {
         ( _elements[i]->*_stop_f_pt)() ;
      }
      pthread_detach(*_threads[i]);
      --_totalRunningThreads;
    }

    void stopAll()  
    {
      if (_stop_f_pt != NULL) 
        for (int i=0; i<_elements.size(); ++i) 
        {
          ( _elements[i]->*_stop_f_pt)() ;
        }
      _totalRunningThreads=0;
    }
};
#endif
// end of test.h

// A usage example file "test.cc" that on linux I've compiled with The class that incapsulates all the work to thread-ize a method: g++ -o mytest.exe test.cc -I. -lpthread -lstdc++

#include <test.h>
#include <vector>
#include <iostream>
#include <Mutex.h>

using namespace std;

// Just a class for which I need to "thread-ize" a some methods
// Given that with OOP the objecs include both "functions" (methods)
// and data (attributes), then there is no need to use function arguments,
// just a "void xxx (void)" method.
// 
class TPuck
{
  public:
   bool _go;
   TPuck(int pVal):_go(true)
   {
     Value = pVal;
   }
   TPuck():_go(true)
   {
   }
   int Value;
   int vc;

   void setValue(int p){Value = p; }

   void super()
   {
     while (_go)
     {
      cout <<"super " << vc << endl;
            sleep(2);
         }
      cout <<"end of super " << vc << endl;
   }

   void vusss()
   {
     while (_go)
     {
      cout <<"vusss " << vc << endl;
      sleep(2);
     }
      cout <<"end of vusss " << vc << endl;
   }

   void fazz()
   {
     static int vcount =0;
     vc = vcount++;
     cout <<"Puck create instance: " << vc << endl;
     while (_go)
     {
       cout <<"fazz " << vc << endl;
       sleep(2);
     }
     cout <<"Completed TPuck..fazz instance "<<  vc << endl;
   }

   void stop()
   {
      _go=false;
      cout << endl << "Stopping TPuck...." << vc << endl;
   }
};


int main(int argc, char* argv[])
{
  // just a number of instances of the class I need to make threads
  int vN = 3;

  // This object will be your threads maker.
  // Just declare an instance for each class
  // you need to create method threads
  //
  CSThread<TPuck> PuckThreadMaker;
  //
  // Hera I'm telling which methods should be threaded
  PuckThreadMaker.addThread(&TPuck::fazz, "fazz1");
  PuckThreadMaker.addThread(&TPuck::fazz, "fazz2");
  PuckThreadMaker.addThread(&TPuck::fazz, "fazz3");
  PuckThreadMaker.addThread(&TPuck::vusss, "vusss");
  PuckThreadMaker.addThread(&TPuck::super, "super");

  PuckThreadMaker.addStopMethod(&TPuck::stop);

  for (int ii=0; ii<vN; ++ii)
  {
    // Creating instances of the class that I need to run threads.
    // If you already have your instances, then just pass them as a
    // parameter such "mythreadmaker.addElement(&myinstance);"
    TPuck * vOne = PuckThreadMaker.addElement();
  }

  if (PuckThreadMaker.run() == true)
  {
    cout <<"All running!" << endl;
  }
  else
  {
    cout <<"Error: not all threads running!" << endl;
  }

  sleep(1);
  cout <<"Totale threads creati: " << PuckThreadMaker.runningThreadsCount()  << endl;
  for (unsigned int ii=0; ii<vN; ++ii)
  {
    unsigned int kk=0;
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
  }

  sleep(2);
  PuckThreadMaker.stopAll();
  cout <<"\n\nAfter the stop!!!!" << endl;
  sleep(2);

  for (int ii=0; ii<vN; ++ii)
  {
    int kk=0;
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
    cout <<"status for element " << ii << " is " << PuckThreadMaker.getStatusStr(ii, kk++) << endl; 
  }

  sleep(5);
  return 0;
}

// End of test.cc

How do I create an average from a Ruby array?

I believe the simplest answer is

list.reduce(:+).to_f / list.size

Java how to sort a Linked List?

Elegant solution since JAVA 8:

LinkedList<String>list = new LinkedList<String>();
list.add("abc");
list.add("Bcd");
list.add("aAb");

list.sort(String::compareToIgnoreCase);

Another option would be using lambda expressions:

list.sort((o1, o2) -> o1.compareToIgnoreCase(o2));

How do I get the path to the current script with Node.js?

If you want something more like $0 in a shell script, try this:

var path = require('path');

var command = getCurrentScriptPath();

console.log(`Usage: ${command} <foo> <bar>`);

function getCurrentScriptPath () {
    // Relative path from current working directory to the location of this script
    var pathToScript = path.relative(process.cwd(), __filename);

    // Check if current working dir is the same as the script
    if (process.cwd() === __dirname) {
        // E.g. "./foobar.js"
        return '.' + path.sep + pathToScript;
    } else {
        // E.g. "foo/bar/baz.js"
        return pathToScript;
    }
}

Interfaces with static fields in java for sharing 'constants'

It's generally considered bad practice. The problem is that the constants are part of the public "interface" (for want of a better word) of the implementing class. This means that the implementing class is publishing all of these values to external classes even when they are only required internally. The constants proliferate throughout the code. An example is the SwingConstants interface in Swing, which is implemented by dozens of classes that all "re-export" all of its constants (even the ones that they don't use) as their own.

But don't just take my word for it, Josh Bloch also says it's bad:

The constant interface pattern is a poor use of interfaces. That a class uses some constants internally is an implementation detail. Implementing a constant interface causes this implementation detail to leak into the class's exported API. It is of no consequence to the users of a class that the class implements a constant interface. In fact, it may even confuse them. Worse, it represents a commitment: if in a future release the class is modified so that it no longer needs to use the constants, it still must implement the interface to ensure binary compatibility. If a nonfinal class implements a constant interface, all of its subclasses will have their namespaces polluted by the constants in the interface.

An enum may be a better approach. Or you could simply put the constants as public static fields in a class that cannot be instantiated. This allows another class to access them without polluting its own API.

sql: check if entry in table A exists in table B

The classical answer that works in almost every environment is

SELECT ID, Name, blah, blah
FROM TableB TB
LEFT JOIN TableA TA
ON TB.ID=TA.ID
WHERE TA.ID IS NULL

sometimes NOT EXISTS may be not implemented (not working).

ERROR 1115 (42000): Unknown character set: 'utf8mb4'

maybe whole database + tables + fields should have the same charset??!

i.e.

CREATE TABLE `politicas` (
  `ID` int(11) NOT NULL AUTO_INCREMENT,
  `Nombre` varchar(250) CHARACTER SET utf8 NOT NULL,
  -------------------------------------^here!!!!!!!!!!!
  PRIMARY KEY (`ID`)
) ENGINE=MyISAM AUTO_INCREMENT=3 DEFAULT CHARSET=utf8;
  -------------------------------------------------^here!!!!!!!!!

Passing dynamic javascript values using Url.action()

This answer might not be 100% relevant to the question. But it does address the problem. I found this simple way of achieving this requirement. Code goes below:

<a href="@Url.Action("Display", "Customer")?custId={{cust.Id}}"></a>

In the above example {{cust.Id}} is an AngularJS variable. However one can replace it with a JavaScript variable.

I haven't tried passing multiple variables using this method but I'm hopeful that also can be appended to the Url if required.

Closing Excel Application using VBA

I think your problem is that it's closing the document that calls the macro before sending the command to quit the application.

Your solution in that case is to not send a command to close the workbook. Instead, you could set the "Saved" state of the workbook to true, which would circumvent any messages about closing an unsaved book. Note: this does not save the workbook; it just makes it look like it's saved.

ThisWorkbook.Saved = True

and then, right after

Application.Quit

How to trigger a click on a link using jQuery

With the code you provided, you cannot expect anything to happen. I second @mashappslabs : first add an event handler :

$("selector").click(function() {
    console.log("element was clicked"); // or alert("click");
});

then trigger your event :

$("selector").click(); //or
$("selector").trigger("click");

and you should see the message in your console.

Bash write to file without echo?

awk ' BEGIN { print "Hello, world" } ' > test.txt

would do it

Calling another different view from the controller using ASP.NET MVC 4

Also, you can just set the ViewName:

return View("ViewName");

Full controller example:

public ActionResult SomeAction() {
    if (condition)
    {
        return View("CustomView");
    }else{
        return View();
    }
}

This works on MVC 5.

How to delete or add column in SQLITE?

I guess what you are wanting to do is database migration. 'Drop'ping a column does not exist in SQLite. But you can however, add an extra column by using the ALTER table query.

Validate decimal numbers in JavaScript - IsNumeric()

function isNumeric(n) {
    var isNumber = true;

    $.each(n.replace(/ /g,'').toString(), function(i, v){
        if(v!=',' && v!='.' && v!='-'){
            if(isNaN(v)){
               isNumber = false;
               return false;
            }
         }
     });

    return isNumber;
}

isNumeric(-3,4567.89);   // true <br>

isNumeric(3,4567.89);   // true <br>

isNumeric("-3,4567.89");   // true <br>

isNumeric(3d,4567.89);   // false

Efficient way to remove ALL whitespace from String?

Using Linq, you can write a readable method this way :

    public static string RemoveAllWhitespaces(this string source)
    {
        return string.IsNullOrEmpty(source) ? source : new string(source.Where(x => !char.IsWhiteSpace(x)).ToArray());
    }

Copy Image from Remote Server Over HTTP

If you have PHP5 and the HTTP stream wrapper enabled on your server, it's incredibly simple to copy it to a local file:

copy('http://somedomain.com/file.jpeg', '/tmp/file.jpeg');

This will take care of any pipelining etc. that's needed. If you need to provide some HTTP parameters there is a third 'stream context' parameter you can provide.

How to Use UTF-8 Collation in SQL Server database?

Looks like this will be finally supported in the SQL Server 2019! SQL Server 2019 - whats new?

From BOL:

UTF-8 support

Full support for the widely used UTF-8 character encoding as an import or export encoding, or as database-level or column-level collation for text data. UTF-8 is allowed in the CHAR and VARCHAR datatypes, and is enabled when creating or changing an object’s collation to a collation with the UTF8 suffix.

For example,LATIN1_GENERAL_100_CI_AS_SC to LATIN1_GENERAL_100_CI_AS_SC_UTF8. UTF-8 is only available to Windows collations that support supplementary characters, as introduced in SQL Server 2012. NCHAR and NVARCHAR allow UTF-16 encoding only, and remain unchanged.

This feature may provide significant storage savings, depending on the character set in use. For example, changing an existing column data type with ASCII strings from NCHAR(10) to CHAR(10) using an UTF-8 enabled collation, translates into nearly 50% reduction in storage requirements. This reduction is because NCHAR(10) requires 22 bytes for storage, whereas CHAR(10) requires 12 bytes for the same Unicode string.

2019-05-14 update:

Documentation seems to be updated now and explains our options staring in MSSQL 2019 in section "Collation and Unicode Support".

2019-07-24 update:

Article by Pedro Lopes - Senior Program Manager @ Microsoft about introducing UTF-8 support for Azure SQL Database

How to check if an app is installed from a web-page on an iPhone?

Didn't read all of these but may be use an iframe and adding the source to, "my app://whatever".

Then check regularly on set interval of the page is 404or not.

You could also use Ajax call. If 404 response then app is not installed.

How to read text file in JavaScript

Javascript doesn't have access to the user's filesystem for security reasons. FileReader is only for files manually selected by the user.

get selected value in datePicker and format it

$('#scheduleDate').datepicker({ dateFormat : 'dd, MM, yy'});

var dateFormat = $('#scheduleDate').datepicker('option', 'dd, MM, yy');

$('#scheduleDate').datepicker('option', 'dateFormat', 'dd, MM, yy');

var result = $('#scheduleDate').val();

alert('result: ' + result);

result: 20, April, 2012

ImportError: numpy.core.multiarray failed to import

I was able to solve the problem by updating my python to 3.8. I am using Macbook Air with Catalina. The problem started for me after updating TensorFlow. After updating it, the error doesn't disappear after I uninstalled and installed numpy several times.

Finally, I downloaded the python3.8 package from python website and installed. Then I installed numpy and it worked.

Chrome net::ERR_INCOMPLETE_CHUNKED_ENCODING error

this was happening for me for a different reason altogether. net::ERR_INCOMPLETE_CHUNKED_ENCODING 200 when i inspect the page and go to newtork tab, i see that the vendor.js page has failed to load. Upon checking it seems that the size of the js file is big ~ 6.5 mb.Thats when i realised that i needed to compress the js. I checked that I was using ng build command to build. Instead when i used ng build --prod --aot --vendor-chunk --common-chunk --delete-output-path --buildOptimizer it worked for me.see https://github.com/angular/angular-cli/issues/9016

How to write a shell script that runs some commands as superuser and some commands not as superuser, without having to babysit it?

You should run your entire script as superuser. If you want to run some command as non-superuser, use "-u" option of sudo:

#!/bin/bash

sudo -u username command1
command2
sudo -u username command3
command4

When running as root, sudo doesn't ask for a password.

Format number to always show 2 decimal places

Number(1).toFixed(2);         // 1.00
Number(1.341).toFixed(2);     // 1.34
Number(1.345).toFixed(2);     // 1.34 NOTE: See andy's comment below.
Number(1.3450001).toFixed(2); // 1.35

_x000D_
_x000D_
document.getElementById('line1').innerHTML = Number(1).toFixed(2);_x000D_
document.getElementById('line2').innerHTML = Number(1.341).toFixed(2);_x000D_
document.getElementById('line3').innerHTML = Number(1.345).toFixed(2);_x000D_
document.getElementById('line4').innerHTML = Number(1.3450001).toFixed(2);
_x000D_
<span id="line1"></span>_x000D_
<br/>_x000D_
<span id="line2"></span>_x000D_
<br/>_x000D_
<span id="line3"></span>_x000D_
<br/>_x000D_
<span id="line4"></span>
_x000D_
_x000D_
_x000D_

Python loop for inside lambda

To add on to chepner's answer for Python 3.0 you can alternatively do:

x = lambda x: list(map(print, x))

Of course this is only if you have the means of using Python > 3 in the future... Looks a bit cleaner in my opinion, but it also has a weird return value, but you're probably discarding it anyway.

I'll just leave this here for reference.

Manually Triggering Form Validation using jQuery

You can't trigger the native validation UI (see edit below), but you can easily take advantage of the validation API on arbitrary input elements:

$('input').blur(function(event) {
    event.target.checkValidity();
}).bind('invalid', function(event) {
    setTimeout(function() { $(event.target).focus();}, 50);
});

The first event fires checkValidity on every input element as soon as it loses focus, if the element is invalid then the corresponding event will be fired and trapped by the second event handler. This one sets the focus back to the element, but that could be quite annoying, I assume you have a better solution for notifying about the errors. Here's a working example of my code above.

EDIT: All modern browsers support the reportValidity() method for native HTML5 validation, per this answer.

How to inspect Javascript Objects

This is blatant rip-off of Christian's excellent answer. I've just made it a bit more readable:

/**
 * objectInspector digs through a Javascript object
 * to display all its properties
 *
 * @param object - a Javascript object to inspect
 * @param result - a string of properties with datatypes
 *
 * @return result - the concatenated description of all object properties
 */
function objectInspector(object, result) {
    if (typeof object != "object")
        return "Invalid object";
    if (typeof result == "undefined")
        result = '';

    if (result.length > 50)
        return "[RECURSION TOO DEEP. ABORTING.]";

    var rows = [];
    for (var property in object) {
        var datatype = typeof object[property];

        var tempDescription = result+'"'+property+'"';
        tempDescription += ' ('+datatype+') => ';
        if (datatype == "object")
            tempDescription += 'object: '+objectInspector(object[property],result+'  ');
        else
            tempDescription += object[property];

        rows.push(tempDescription);
    }//Close for

    return rows.join(result+"\n");
}//End objectInspector

Best way to use PHP to encrypt and decrypt passwords?

Security warning: This code is not secure.

working example

define('SALT', 'whateveryouwant'); 

function encrypt($text) 
{ 
    return trim(base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, SALT, $text, MCRYPT_MODE_ECB, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND)))); 
} 

function decrypt($text) 
{ 
    return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, SALT, base64_decode($text), MCRYPT_MODE_ECB, mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND))); 
} 

$encryptedmessage = encrypt("your message"); 
echo decrypt($encryptedmessage); 

What is the difference between `let` and `var` in swift?

The main difference is that var variable value can change, and let can't. If you want to have a user input data, you would use var so the value can be changed and use let datatype variable so the value can not be changed.

var str      = "dog"  // str value is "dog"
str          = "cat"  // str value is now "cat"

let strAnimal = "dog" // strAnimal value is "dog"
strAnimal     = "cat" // Error !

How do I convert NSInteger to NSString datatype?

Obj-C way =):

NSString *inStr = [@(month) stringValue];

Direct download from Google Drive using Google Drive API

https://github.com/google/skicka

I used this command line tool to download files from Google Drive. Just follow the instructions in Getting Started section and you should download files from Google Drive in minutes.

How to vertically center a "div" element for all browsers using CSS?

This is by far the easiest approach, works on non-blocking elements as well, the only downside is, it's Flexbox, thus, older browsers will not support this.

<div class="sweet-overlay">
    <img class="centered" src="http://jimpunk.com/Loading/loading83.gif" />
</div>

Link to codepen:

http://codepen.io/damianocel/pen/LNOdRp

The important point here is, for vertical centering, we need to define a parent element (container) and the img must have a smaller height than the parent element.

Why use HttpClient for Synchronous Connection

public static class AsyncHelper  
{
    private static readonly TaskFactory _taskFactory = new
        TaskFactory(CancellationToken.None,
                    TaskCreationOptions.None,
                    TaskContinuationOptions.None,
                    TaskScheduler.Default);

    public static TResult RunSync<TResult>(Func<Task<TResult>> func)
        => _taskFactory
            .StartNew(func)
            .Unwrap()
            .GetAwaiter()
            .GetResult();

    public static void RunSync(Func<Task> func)
        => _taskFactory
            .StartNew(func)
            .Unwrap()
            .GetAwaiter()
            .GetResult();
}

Then

AsyncHelper.RunSync(() => DoAsyncStuff());

if you use that class pass your async method as parameter you can call the async methods from sync methods in a safe way.

it's explained here : https://cpratt.co/async-tips-tricks/

Counting number of characters in a file through shell script

awk '{t+=length($0)}END{print t}' file3

Create list of object from another using Java 8 Streams

An addition to the solution by @Rafael Teles. The syntactic sugar Collectors.mapping does the same in one step:

//...
List<Employee> employees = persons.stream()
  .filter(p -> p.getLastName().equals("l1"))
  .collect(
    Collectors.mapping(
      p -> new Employee(p.getName(), p.getLastName(), 1000),
      Collectors.toList()));

Detailed example can be found here

What is the largest Safe UDP Packet Size on the Internet

I fear i incur upset reactions but nevertheless, to clarify for me if i'm wrong or those seeing this question and being interested in an answer:

my understanding of https://tools.ietf.org/html/rfc1122 whose status is "an official specification" and as such is the reference for the terminology used in this question and which is neither superseded by another RFC nor has errata contradicting the following:

theoretically, ie. based on the written spec., UDP like given by https://tools.ietf.org/html/rfc1122#section-4 has no "packet size". Thus the answer could be "indefinite"

In practice, which is what this questions likely seeked (and which could be updated for current tech in action), this might be different and I don't know.

I apologize if i caused upsetting. https://tools.ietf.org/html/rfc1122#page-8 The "Internet Protocol Suite" and "Architectural Assumptions" don't make clear to me the "assumption" i was on, based on what I heard, that the layers are separate. Ie. the layer UDP is in does not have to concern itself with the layer IP is in (and the IP layer does have things like Reassembly, EMTU_R, Fragmentation and MMS_R (https://tools.ietf.org/html/rfc1122#page-56))

Write a formula in an Excel Cell using VBA

I don't know why, but if you use

(...)Formula = "=SUM(D2,E2)"

(',' instead of ';'), it works.

If you step through your sub in the VB script editor (F8), you can add Range("F2").Formula to the watch window and see what the formular looks like from a VB point of view. It seems that the formular shown in Excel itself is sometimes different from the formular that VB sees...

Update style of a component onScroll in React.js

To expand on @Austin's answer, you should add this.handleScroll = this.handleScroll.bind(this) to your constructor:

constructor(props){
    this.handleScroll = this.handleScroll.bind(this)
}
componentDidMount: function() {
    window.addEventListener('scroll', this.handleScroll);
},

componentWillUnmount: function() {
    window.removeEventListener('scroll', this.handleScroll);
},

handleScroll: function(event) {
    let scrollTop = event.srcElement.body.scrollTop,
        itemTranslate = Math.min(0, scrollTop/3 - 60);

    this.setState({
      transform: itemTranslate
    });
},
...

This gives handleScroll() access to the proper scope when called from the event listener.

Also be aware you cannot do the .bind(this) in the addEventListener or removeEventListener methods because they will each return references to different functions and the event will not be removed when the component unmounts.

How to open a file / browse dialog using javascript?

Use this.

<script>
  function openFileOption()
{
  document.getElementById("file1").click();
}
</script>
     <input type="file" id="file1" style="display:none">
     <a href="#" onclick="openFileOption();return;">open File Dialog</a>

How to always show scrollbar

Simple and easy. Add this attribute to the ScrollBar:

android:fadeScrollbars="false"

Or you can do this in :

scrollView.setScrollbarFadingEnabled(false);

Or in :

scrollView.isScrollbarFadingEnabled = false

How to implement "select all" check box in HTML?

As I cannot comment, here as answer: I would write Can Berk Güder's solution in a more general way, so you may reuse the function for other checkboxes

<script language="JavaScript">
  function toggleCheckboxes(source, cbName) {
    checkboxes = document.getElementsByName(cbName);
    for (var i = 0, n = checkboxes.length; i < n; i++) {
      checkboxes[i].checked = source.checked;
    }
  }
</script>
<input type="checkbox" onClick="toggleCheckboxes(this,\'foo\')" /> Toggle All<br/>

<input type="checkbox" name="foo" value="bar1"> Bar 1<br/>
<input type="checkbox" name="foo" value="bar2"> Bar 2<br/>
<input type="checkbox" name="foo" value="bar3"> Bar 3<br/>
<input type="checkbox" name="foo" value="bar4"> Bar 4<br/>
<input type="checkbox" name="foo" value="bar5"> Bar 5<br/>

How to use a WSDL

I would fire up Visual Studio, create a web project (or console app - doesn't matter).

For .Net Standard:

  1. I would right-click on the project and pick "Add Service Reference" from the Add context menu.
  2. I would click on Advanced, then click on Add Service Reference.
  3. I would get the complete file path of the wsdl and paste into the address bar. Then fire the Arrow (go button).
  4. If there is an error trying to load the file, then there must be a broken and unresolved url the file needs to resolve as shown below: enter image description here Refer to this answer for information on how to fix: Stackoverflow answer to: Unable to create service reference for wsdl file

If there is no error, you should simply set the NameSpace you want to use to access the service and it'll be generated for you.

For .Net Core

  1. I would right click on the project and pick Connected Service from the Add context menu.
  2. I would select Microsoft WCF Web Service Reference Provider from the list.
  3. I would press browse and select the wsdl file straight away, Set the namespace and I am good to go. Refer to the error fix url above if you encounter any error.

Any of the methods above will generate a simple, very basic WCF client for you to use. You should find a "YourservicenameClient" class in the generated code.

For reference purpose, the generated cs file can be found in your Obj/debug(or release)/XsdGeneratedCode and you can still find the dlls in the TempPE folder.

The created Service(s) should have methods for each of the defined methods on the WSDL contract.

Instantiate the client and call the methods you want to call - that's all there is!

YourServiceClient client = new YourServiceClient();
client.SayHello("World!");

If you need to specify the remote URL (not using the one created by default), you can easily do this in the constructor of the proxy client:

YourServiceClient client = new YourServiceClient("configName", "remoteURL");

where configName is the name of the endpoint to use (you will use all the settings except the URL), and the remoteURL is a string representing the URL to connect to (instead of the one contained in the config).

Short rot13 function - Python

This works for uppercase and lowercase. I don't know how elegant you deem it to be.

def rot13(s):
    rot=lambda x:chr(ord(x)+13) if chr(ord(x.lower())+13).isalpha()==True else chr(ord(x)-13)
    s=[rot(i) for i in filter(lambda x:x!=',',map(str,s))]
    return ''.join(s)

How do I make a fully statically linked .exe with Visual Studio Express 2005?

My experience in Visual Studio 2010 is that there are two changes needed so as to not need DLL's. From the project property page (right click on the project name in the Solution Explorer window):

  1. Under Configuration Properties --> General, change the "Use of MFC" field to "Use MFC in a Static Library".

  2. Under Configuration Properties --> C/C++ --> Code Generation, change the "Runtime Library" field to "Multi-Threaded (/MT)"

Not sure why both were needed. I used this to remove a dependency on glut32.dll.

Added later: When making these changes to the configurations, you should make them to "All Configurations" --- you can select this at the top of the Properties window. If you make the change to just the Debug configuration, it won't apply to the Release configuration, and vice-versa.

How do I get values from a SQL database into textboxes using C#?

Make a connection and open it.

con = new OracleConnection("Data Source=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1521)))(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=<database_name>)));User Id =<userid>; Password =<password>");
con.Open();

Write the select query:

string sql = "select * from Pending_Tasks";

Create a command object:

OracleCommand cmd = new OracleCommand(sql, con);

Execute the command and put the result in a object to read it.

OracleDataReader r = cmd.ExecuteReader();

now start reading from it.

while (read.Read())
{
 CustID.Text = (read["Customer_ID"].ToString());
 CustName.Text = (read["Customer_Name"].ToString());
 Add1.Text = (read["Address_1"].ToString());
 Add2.Text = (read["Address_2"].ToString());
 PostBox.Text = (read["Postcode"].ToString());
 PassBox.Text = (read["Password"].ToString());
 DatBox.Text = (read["Data_Important"].ToString());
 LanNumb.Text = (read["Landline"].ToString());
 MobNumber.Text = (read["Mobile"].ToString());
 FaultRep.Text = (read["Fault_Report"].ToString());
}
read.Close();

Add this too using Oracle.ManagedDataAccess.Client;

Timing a command's execution in PowerShell

Here's a function I wrote which works similarly to the Unix time command:

function time {
    Param(
        [Parameter(Mandatory=$true)]
        [string]$command,
        [switch]$quiet = $false
    )
    $start = Get-Date
    try {
        if ( -not $quiet ) {
            iex $command | Write-Host
        } else {
            iex $command > $null
        }
    } finally {
        $(Get-Date) - $start
    }
}

Source: https://gist.github.com/bender-the-greatest/741f696d965ed9728dc6287bdd336874

How can I specify the schema to run an sql file against in the Postgresql command line

The PGOPTIONS environment variable may be used to achieve this in a flexible way.

In an Unix shell:

PGOPTIONS="--search_path=my_schema_01" psql -d myDataBase -a -f myInsertFile.sql

If there are several invocations in the script or sub-shells that need the same options, it's simpler to set PGOPTIONS only once and export it.

PGOPTIONS="--search_path=my_schema_01"
export PGOPTIONS

psql -d somebase
psql -d someotherbase
...

or invoke the top-level shell script with PGOPTIONS set from the outside

PGOPTIONS="--search_path=my_schema_01"  ./my-upgrade-script.sh

In Windows CMD environment, set PGOPTIONS=value should work the same.

How to submit an HTML form on loading the page?

using javascript

 <form id="frm1" action="file.php"></form>
    <script>document.getElementById('frm1').submit();</script>

How to call python script on excel vba?

This code will works:

 your_path= ActiveWorkbook.Path & "\your_python_file.py" 
 Shell "RunDll32.Exe Url.Dll,FileProtocolHandler " & your_path, vbNormalFocus 

ActiveWorkbook.Path return the current directory of the workbook. The shell command open the file through the shell of Windows.

How to check if a variable is an integer or a string?

Depending on your definition of shortly, you could use one of the following options:

Select from where field not equal to Mysql Php

You can use like

NOT columnA = 'x'

Or

columnA != 'x'

Or

columnA <> 'x'

And like Jeffly Bake's query, for including null values, you don't have to write like

(NOT columnA = 'x' OR columnA IS NULL)

You can make it simple by

Not columnA <=> 'x'

<=> is the Null Safe equal to Operator, which includes results from even null values.

vue.js 'document.getElementById' shorthand

You can use the directive v-el to save an element and then use it later.

https://vuejs.org/api/#vm-els

<div v-el:my-div></div>
<!-- this.$els.myDiv --->

Edit: This is deprecated in Vue 2, see ??? answer

Check Postgres access for a user

You could query the table_privileges table in the information schema:

SELECT table_catalog, table_schema, table_name, privilege_type
FROM   information_schema.table_privileges 
WHERE  grantee = 'MY_USER'

How to check if an element is in an array

(Swift 3)

Check if an element exists in an array (fulfilling some criteria), and if so, proceed working with the first such element

If the intent is:

  1. To check whether an element exist in an array (/fulfils some boolean criteria, not necessarily equality testing),
  2. And if so, proceed and work with the first such element,

Then an alternative to contains(_:) as blueprinted Sequence is to first(where:) of Sequence:

let elements = [1, 2, 3, 4, 5]

if let firstSuchElement = elements.first(where: { $0 == 4 }) {
    print(firstSuchElement) // 4
    // ...
}

In this contrived example, its usage might seem silly, but it's very useful if querying arrays of non-fundamental element types for existence of any elements fulfilling some condition. E.g.

struct Person {
    let age: Int
    let name: String
    init(_ age: Int, _ name: String) {
        self.age = age
        self.name = name
    }
}

let persons = [Person(17, "Fred"),   Person(16, "Susan"),
               Person(19, "Hannah"), Person(18, "Sarah"),
               Person(23, "Sam"),    Person(18, "Jane")]

if let eligableDriver = persons.first(where: { $0.age >= 18 }) {
    print("\(eligableDriver.name) can possibly drive the rental car in Sweden.")
    // ...
} // Hannah can possibly drive the rental car in Sweden.

let daniel = Person(18, "Daniel")
if let sameAgeAsDaniel = persons.first(where: { $0.age == daniel.age }) {
    print("\(sameAgeAsDaniel.name) is the same age as \(daniel.name).")
    // ...
} // Sarah is the same age as Daniel.

Any chained operations using .filter { ... some condition }.first can favourably be replaced with first(where:). The latter shows intent better, and have performance advantages over possible non-lazy appliances of .filter, as these will pass the full array prior to extracting the (possible) first element passing the filter.


Check if an element exists in an array (fulfilling some criteria), and if so, remove the first such element

A comment below queries:

How can I remove the firstSuchElement from the array?

A similar use case to the one above is to remove the first element that fulfils a given predicate. To do so, the index(where:) method of Collection (which is readily available to array collection) may be used to find the index of the first element fulfilling the predicate, whereafter the index can be used with the remove(at:) method of Array to (possible; given that it exists) remove that element.

var elements = ["a", "b", "c", "d", "e", "a", "b", "c"]

if let indexOfFirstSuchElement = elements.index(where: { $0 == "c" }) {
    elements.remove(at: indexOfFirstSuchElement)
    print(elements) // ["a", "b", "d", "e", "a", "b", "c"]
}

Or, if you'd like to remove the element from the array and work with, apply Optional:s map(_:) method to conditionally (for .some(...) return from index(where:)) use the result from index(where:) to remove and capture the removed element from the array (within an optional binding clause).

var elements = ["a", "b", "c", "d", "e", "a", "b", "c"]

if let firstSuchElement = elements.index(where: { $0 == "c" })
    .map({ elements.remove(at: $0) }) {

    // if we enter here, the first such element have now been
    // remove from the array
    print(elements) // ["a", "b", "d", "e", "a", "b", "c"]

    // and we may work with it
    print(firstSuchElement) // c
}

Note that in the contrived example above the array members are simple value types (String instances), so using a predicate to find a given member is somewhat over-kill, as we might simply test for equality using the simpler index(of:) method as shown in @DogCoffee's answer. If applying the find-and-remove approach above to the Person example, however, using index(where:) with a predicate is appropriate (since we no longer test for equality but for fulfilling a supplied predicate).

Script to Change Row Color when a cell changes text

I used GENEGC's script, but I found it quite slow.

It is slow because it scans whole sheet on every edit.

So I wrote way faster and cleaner method for myself and I wanted to share it.

function onEdit(e) {
    if (e) { 
        var ss = e.source.getActiveSheet();
        var r = e.source.getActiveRange(); 

        // If you want to be specific
        // do not work in first row
        // do not work in other sheets except "MySheet"
        if (r.getRow() != 1 && ss.getName() == "MySheet") {

            // E.g. status column is 2nd (B)
            status = ss.getRange(r.getRow(), 2).getValue();

            // Specify the range with which You want to highlight
            // with some reading of API you can easily modify the range selection properties
            // (e.g. to automatically select all columns)
            rowRange = ss.getRange(r.getRow(),1,1,19);

            // This changes font color
            if (status == 'YES') {
                rowRange.setFontColor("#999999");
            } else if (status == 'N/A') {
                rowRange.setFontColor("#999999");
            // DEFAULT
            } else if (status == '') { 
                rowRange.setFontColor("#000000");
            }   
        }
    }
}

How to integrate Dart into a Rails app

If you run pub build --mode=debug the build directory contains the application without symlinks. The Dart code should be retained when --mode=debug is used.

Here is some discussion going on about this topic too Dart and it's place in Rails Assets Pipeline

Attach event to dynamic elements in javascript

I've made a simple function for this.

The _case function allows you to not only get the target, but also get the parent element where you bind the event on.

The callback function returns the event which holds the target (evt.target) and the parent element matching the selector (this). Here you can do the stuff you need after the element is clicked.

I've not yet decided which is better, the if-else or the switch

_x000D_
_x000D_
var _case = function(evt, selector, cb) {_x000D_
  var _this = evt.target.closest(selector);_x000D_
  if (_this && _this.nodeType) {_x000D_
    cb.call(_this, evt);_x000D_
    return true;_x000D_
  } else { return false; }_x000D_
}_x000D_
_x000D_
document.getElementById('ifelse').addEventListener('click', function(evt) {_x000D_
  if (_case(evt, '.parent1', function(evt) {_x000D_
      console.log('1: ', this, evt.target);_x000D_
    })) return false;_x000D_
_x000D_
  if (_case(evt, '.parent2', function(evt) {_x000D_
      console.log('2: ', this, evt.target);_x000D_
    })) return false;_x000D_
_x000D_
  console.log('ifelse: ', this);_x000D_
})_x000D_
_x000D_
_x000D_
document.getElementById('switch').addEventListener('click', function(evt) {_x000D_
  switch (true) {_x000D_
    case _case(evt, '.parent3', function(evt) {_x000D_
      console.log('3: ', this, evt.target);_x000D_
    }): break;_x000D_
    case _case(evt, '.parent4', function(evt) {_x000D_
      console.log('4: ', this, evt.target);_x000D_
    }): break;_x000D_
    default:_x000D_
      console.log('switch: ', this);_x000D_
      break;_x000D_
  }_x000D_
})
_x000D_
#ifelse {_x000D_
  background: red;_x000D_
  height: 100px;_x000D_
}_x000D_
#switch {_x000D_
  background: yellow;_x000D_
  height: 100px;_x000D_
}
_x000D_
<div id="ifelse">_x000D_
  <div class="parent1">_x000D_
    <div class="child1">Click me 1!</div>_x000D_
  </div>_x000D_
  <div class="parent2">_x000D_
    <div class="child2">Click me 2!</div>_x000D_
  </div>_x000D_
</div>_x000D_
_x000D_
<div id="switch">_x000D_
  <div class="parent3">_x000D_
    <div class="child3">Click me 3!</div>_x000D_
  </div>_x000D_
  <div class="parent4">_x000D_
    <div class="child4">Click me 4!</div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Hope it helps!

how to calculate percentage in python

Percent calculation that worked for me:

(new_num - old_num) / old_num * 100.0

The data-toggle attributes in Twitter Bootstrap

From the Bootstrap Docs:

<!--Activate a modal without writing JavaScript. Set data-toggle="modal" on a 
controller element, like a button, along with a data-target="#foo" or href="#foo" 
to target a specific modal to toggle.-->

<button type="button" data-toggle="modal" data-target="#myModal">Launch modal</button>

When I catch an exception, how do I get the type, file, and line number?

Source (Py v2.7.3) for traceback.format_exception() and called/related functions helps greatly. Embarrassingly, I always forget to Read the Source. I only did so for this after searching for similar details in vain. A simple question, "How to recreate the same output as Python for an exception, with all the same details?" This would get anybody 90+% to whatever they're looking for. Frustrated, I came up with this example. I hope it helps others. (It sure helped me! ;-)

import sys, traceback

traceback_template = '''Traceback (most recent call last):
  File "%(filename)s", line %(lineno)s, in %(name)s
%(type)s: %(message)s\n''' # Skipping the "actual line" item

# Also note: we don't walk all the way through the frame stack in this example
# see hg.python.org/cpython/file/8dffb76faacc/Lib/traceback.py#l280
# (Imagine if the 1/0, below, were replaced by a call to test() which did 1/0.)

try:
    1/0
except:
    # http://docs.python.org/2/library/sys.html#sys.exc_info
    exc_type, exc_value, exc_traceback = sys.exc_info() # most recent (if any) by default

    '''
    Reason this _can_ be bad: If an (unhandled) exception happens AFTER this,
    or if we do not delete the labels on (not much) older versions of Py, the
    reference we created can linger.

    traceback.format_exc/print_exc do this very thing, BUT note this creates a
    temp scope within the function.
    '''

    traceback_details = {
                         'filename': exc_traceback.tb_frame.f_code.co_filename,
                         'lineno'  : exc_traceback.tb_lineno,
                         'name'    : exc_traceback.tb_frame.f_code.co_name,
                         'type'    : exc_type.__name__,
                         'message' : exc_value.message, # or see traceback._some_str()
                        }

    del(exc_type, exc_value, exc_traceback) # So we don't leave our local labels/objects dangling
    # This still isn't "completely safe", though!
    # "Best (recommended) practice: replace all exc_type, exc_value, exc_traceback
    # with sys.exc_info()[0], sys.exc_info()[1], sys.exc_info()[2]

    print
    print traceback.format_exc()
    print
    print traceback_template % traceback_details
    print

In specific answer to this query:

sys.exc_info()[0].__name__, os.path.basename(sys.exc_info()[2].tb_frame.f_code.co_filename), sys.exc_info()[2].tb_lineno

How to multiply all integers inside list

Try a list comprehension:

l = [x * 2 for x in l]

This goes through l, multiplying each element by two.

Of course, there's more than one way to do it. If you're into lambda functions and map, you can even do

l = map(lambda x: x * 2, l)

to apply the function lambda x: x * 2 to each element in l. This is equivalent to:

def timesTwo(x):
    return x * 2

l = map(timesTwo, l)

Note that map() returns a map object, not a list, so if you really need a list afterwards you can use the list() function afterwards, for instance:

l = list(map(timesTwo, l))

Thanks to Minyc510 in the comments for this clarification.

Get selected key/value of a combo box using jQuery

I assume by "key" and "value" you mean:

<select>
    <option value="KEY">VALUE</option>
</select>

If that's the case, this will get you the "VALUE":

$(this).find('option:selected').text();

And you can get the "KEY" like this:

$(this).find('option:selected').val();

Error: The 'brew link' step did not complete successfully

by the Finder, Delete this file:

/usr/local/lib/dtrace/node.d

in terminal:

$ brew link --overwrite --dry-run node

then:

$ brew link node

What is the difference between x86 and x64

x64 is a generic name for the 64-bit extensions to Intel's and AMD's 32-bit x86 instruction set architecture (ISA). AMD introduced the first version of x64, initially called x86-64 and later renamed AMD64. Intel named their implementation IA-32e and then EMT64.

How to use variables in a command in sed?

This may also can help

input="inputtext"
output="outputtext"
sed "s/$input/${output}/" inputfile > outputfile

The type List is not generic; it cannot be parameterized with arguments [HTTPClient]

Try to import

java.util.List;

instead of

java.awt.List;

Passing variables to the next middleware using next() in Express.js

This is what the res.locals object is for. Setting variables directly on the request object is not supported or documented. res.locals is guaranteed to hold state over the life of a request.

res.locals

An object that contains response local variables scoped to the request, and therefore available only to the view(s) rendered during that request / response cycle (if any). Otherwise, this property is identical to app.locals.

This property is useful for exposing request-level information such as the request path name, authenticated user, user settings, and so on.

app.use(function(req, res, next) {
    res.locals.user = req.user;  
    res.locals.authenticated = !req.user.anonymous;
    next();
});

To retrieve the variable in the next middleware:

app.use(function(req, res, next) {
    if (res.locals.authenticated) {
        console.log(res.locals.user.id);
    }
    next();
});

How do I set default value of select box in angularjs

After searching and trying multiple non working options to get my select default option working. I find a clean solution at: http://www.undefinednull.com/2014/08/11/a-brief-walk-through-of-the-ng-options-in-angularjs/

<select class="ajg-stereo-fader-input-name ajg-select-left"  ng-options="option.name for option in selectOptions" ng-model="inputLeft"></select>
<select class="ajg-stereo-fader-input-name ajg-select-right" ng-options="option.name for option in selectOptions" ng-model="inputRight"></select>

 scope.inputLeft =  scope.selectOptions[0];
 scope.inputRight = scope.selectOptions[1];

Octave/Matlab: Adding new elements to a vector

As mentioned before, the use of x(end+1) = newElem has the advantage that it allows you to concatenate your vector with a scalar, regardless of whether your vector is transposed or not. Therefore it is more robust for adding scalars.

However, what should not be forgotten is that x = [x newElem] will also work when you try to add multiple elements at once. Furthermore, this generalizes a bit more naturally to the case where you want to concatenate matrices. M = [M M1 M2 M3]


All in all, if you want a solution that allows you to concatenate your existing vector x with newElem that may or may not be a scalar, this should do the trick:

 x(end+(1:numel(newElem)))=newElem

Is it possible to ping a server from Javascript?

You can't do regular ping in browser Javascript, but you can find out if remote server is alive by for example loading an image from the remote server. If loading fails -> server down.

You can even calculate the loading time by using onload-event. Here's an example how to use onload event.

How to add style from code behind?

You can't.

So just don't apply styles directly like that, and apply a class "foo", and then define that in your CSS specification:

a.foo { color : orange; }
a.foo:hover { font-weight : bold; }

REST API - Bulk Create or Update in single request

I think that you could use a POST or PATCH method to handle this since they typically design for this.

  • Using a POST method is typically used to add an element when used on list resource but you can also support several actions for this method. See this answer: How to Update a REST Resource Collection. You can also support different representation formats for the input (if they correspond to an array or a single elements).

    In the case, it's not necessary to define your format to describe the update.

  • Using a PATCH method is also suitable since corresponding requests correspond to a partial update. According to RFC5789 (http://tools.ietf.org/html/rfc5789):

    Several applications extending the Hypertext Transfer Protocol (HTTP) require a feature to do partial resource modification. The existing HTTP PUT method only allows a complete replacement of a document. This proposal adds a new HTTP method, PATCH, to modify an existing HTTP resource.

    In the case, you have to define your format to describe the partial update.

I think that in this case, POST and PATCH are quite similar since you don't really need to describe the operation to do for each element. I would say that it depends on the format of the representation to send.

The case of PUT is a bit less clear. In fact, when using a method PUT, you should provide the whole list. As a matter of fact, the provided representation in the request will be in replacement of the list resource one.

You can have two options regarding the resource paths.

  • Using the resource path for doc list

In this case, you need to explicitely provide the link of docs with a binder in the representation you provide in the request.

Here is a sample route for this /docs.

The content of such approach could be for method POST:

[
    { "doc_number": 1, "binder": 4, (other fields in the case of creation) },
    { "doc_number": 2, "binder": 4, (other fields in the case of creation) },
    { "doc_number": 3, "binder": 5, (other fields in the case of creation) },
    (...)
]
  • Using sub resource path of binder element

In addition you could also consider to leverage sub routes to describe the link between docs and binders. The hints regarding the association between a doc and a binder doesn't have now to be specified within the request content.

Here is a sample route for this /binder/{binderId}/docs. In this case, sending a list of docs with a method POST or PATCH will attach docs to the binder with identifier binderId after having created the doc if it doesn't exist.

The content of such approach could be for method POST:

[
    { "doc_number": 1, (other fields in the case of creation) },
    { "doc_number": 2, (other fields in the case of creation) },
    { "doc_number": 3, (other fields in the case of creation) },
    (...)
]

Regarding the response, it's up to you to define the level of response and the errors to return. I see two levels: the status level (global level) and the payload level (thinner level). It's also up to you to define if all the inserts / updates corresponding to your request must be atomic or not.

  • Atomic

In this case, you can leverage the HTTP status. If everything goes well, you get a status 200. If not, another status like 400 if the provided data aren't correct (for example binder id not valid) or something else.

  • Non atomic

In this case, a status 200 will be returned and it's up to the response representation to describe what was done and where errors eventually occur. ElasticSearch has an endpoint in its REST API for bulk update. This could give you some ideas at this level: http://www.elasticsearch.org/guide/en/elasticsearch/guide/current/bulk.html.

  • Asynchronous

You can also implement an asynchronous processing to handle the provided data. In this case, the HTTP status returns will be 202. The client needs to pull an additional resource to see what happens.

Before finishing, I also would want to notice that the OData specification addresses the issue regarding relations between entities with the feature named navigation links. Perhaps could you have a look at this ;-)

The following link can also help you: https://templth.wordpress.com/2014/12/15/designing-a-web-api/.

Hope it helps you, Thierry

reCAPTCHA ERROR: Invalid domain for site key

I had a similar problem due to the fact that I forgot to show the render parameter

<script src='https://www.google.com/recaptcha/api.js?render=SITE_KEY' async defer></script>

This version of the application is not configured for billing through Google Play

If you want to debug IAB what do you have to do is:

  1. Submit to google play a version of your app with the IAB permission on the manifest:

  2. Add a product to your app on google play: Administering In-app Billing

  3. Set a custom debug keystore signed: Configure Eclipse to use signed keystore

How to tag docker image with docker-compose

you can try:

services:
  nameis:
    container_name: hi_my
    build: .
    image: hi_my_nameis:v1.0.0

XPath contains(text(),'some string') doesn't work when used with node with more than one Text subnode

It took me a little while but finally figured out. Custom xpath that contains some text below worked perfectly for me.

//a[contains(text(),'JB-')]

Create Git branch with current changes

To add new changes to a new branch and push to remote:

git branch branch/name
git checkout branch/name
git push origin branch/name

Often times I forget to add the origin part to push and get confused why I don't see the new branch/commit in bitbucket

Create Word Document using PHP in Linux

By far the easiest way to create DOC files on Linux, using PHP is with the Zend Framework component phpLiveDocx.

From the project web site:

"phpLiveDocx allows developers to generate documents by combining structured data from PHP with a template, created in a word processor. The resulting document can be saved as a PDF, DOCX, DOC or RTF file. The concept is the same as with mail-merge."

How can I store the result of a system command in a Perl variable?

Use backticks for system commands, which helps to store their results into Perl variables.

my $pid = 5892;
my $not = ``top -H -p $pid -n 1 | grep myprocess | wc -l`; 
print "not = $not\n";

How to clean node_modules folder of packages that are not in package.json?

I have added few lines inside package.json:

"scripts": {
  ...
  "clean": "rmdir /s /q node_modules",
  "reinstall": "npm run clean && npm install",
  "rebuild": "npm run clean && npm install && rmdir /s /q dist && npm run build --prod",
  ...
}

If you want to clean only you can use this rimraf node_modules or rm -rf node_modules.

It works fine

Count the number of Occurrences of a Word in a String

This will work

int word_count(String text,String key){
   int count=0;
   while(text.contains(key)){
      count++;
      text=text.substring(text.indexOf(key)+key.length());
   }
   return count;
}

How to define and use function inside Jenkins Pipeline config?

First off, you shouldn't add $ when you're outside of strings ($class in your first function being an exception), so it should be:

def doCopyMibArtefactsHere(projectName) {
    step ([
        $class: 'CopyArtifact',
        projectName: projectName,
        filter: '**/**.mib',
        fingerprintArtifacts: true, 
        flatten: true
    ]);
}

def BuildAndCopyMibsHere(projectName, params) {
    build job: project, parameters: params
    doCopyMibArtefactsHere(projectName)
}
...

Now, as for your problem; the second function takes two arguments while you're only supplying one argument at the call. Either you have to supply two arguments at the call:

...
node { 
    stage('Prepare Mib'){
        BuildAndCopyMibsHere('project1', null)
    }
}

... or you need to add a default value to the functions' second argument:

def BuildAndCopyMibsHere(projectName, params = null) {
    build job: project, parameters: params
    doCopyMibArtefactsHere($projectName)
}

Opening A Specific File With A Batch File?

If you are trying to open a file in the same directory it would be:

./PROGRAM TRYING TO OPEN
./FILE NAME/PROGRAM TRYING TO OPEN (or this)

Or, if trying to backtrack from the same directory it would be:

../PROGRAM TRYING TO OPEN
../FILE NAME/PROGRAM TRYING TO OPEN (or this)

Else, if you need a straight one from start, it would be:

(DIRECTORY TYPE)\Users\%username%\(FILE DIRECTORY)
(ex) C:\Users\ajste\Desktop\Henlo.cmd

How can I rename column in laravel using migration?

Renaming Columns (Laravel 5.x)

To rename a column, you may use the renameColumn method on the Schema builder. *Before renaming a column, be sure to add the doctrine/dbal dependency to your composer.json file.*

Or you can simply required the package using composer...

composer require doctrine/dbal

Source: https://laravel.com/docs/5.0/schema#renaming-columns

Note: Use make:migration and not migrate:make for Laravel 5.x

How can I convert an image into a Base64 string?

Use this code:

byte[] decodedString = Base64.decode(Base64String.getBytes(), Base64.DEFAULT);

Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);

Difference between attr_accessor and attr_accessible

attr_accessor is a Ruby method that gives you setter and getter methods to an instance variable of the same name. So it is equivalent to

class MyModel
  def my_variable
    @my_variable
  end
  def my_variable=(value)
    @my_variable = value
  end
end

attr_accessible is a Rails method that determines what variables can be set in a mass assignment.

When you submit a form, and you have something like MyModel.new params[:my_model] then you want to have a little bit more control, so that people can't submit things that you don't want them to.

You might do attr_accessible :email so that when someone updates their account, they can change their email address. But you wouldn't do attr_accessible :email, :salary because then a person could set their salary through a form submission. In other words, they could hack their way to a raise.

That kind of information needs to be explicitly handled. Just removing it from the form isn't enough. Someone could go in with firebug and add the element into the form to submit a salary field. They could use the built in curl to submit a new salary to the controller update method, they could create a script that submits a post with that information.

So attr_accessor is about creating methods to store variables, and attr_accessible is about the security of mass assignments.

Troubleshooting BadImageFormatException

For anyone who may arrive here at a later time...
For Desktop solution I got BadImageFormatException exception.
All project's build options was fine (all x86). But StartUp project of solution was changed to some other project(class library project).

Changing StartUp project to the original(.exe application project) was a solution in my case

Sleep function Visual Basic

This one is much easie.

Threading.Thread.Sleep(3000)

"document.getElementByClass is not a function"

you spelt it wrongly, it should be " getElementsByClassName ",

var objs = document.getElementsByClassName("stopButton");
var stopMusicExt = objs[0]; //retrieve the first node in the stack

//your remaining function goes down here.. 
document['player'].stopMusicExt(ta.value);
ta.value = "";

document.getElementsByClassName - returns a stack of nodes with more than one item, since CLASS attributes are used to assign to multiple objects...

What is the difference between #import and #include in Objective-C?

I agree with Jason.

I got caught out doing this:

#import <sys/time.h>  // to use gettimeofday() function
#import <time.h>      // to use time() function

For GNU gcc, it kept complaining that time() function was not defined.

So then I changed #import to #include and all went ok.

Reason:

You #import <sys/time.h>:
    <sys/time.h> includes only a part of <time.h> by using #defines

You #import <time.h>:
    No go. Even though only part of <time.h> was already included, as
    far as #import is concerned, that file is now already completely included.

Bottom line:

C/C++ headers traditionally includes parts of other include files.
So for C/C++ headers, use #include.
For objc/objc++ headers, use #import.

How do I get the picture size with PIL?

Since scipy's imread is deprecated, use imageio.imread.

  1. Install - pip install imageio
  2. Use height, width, channels = imageio.imread(filepath).shape

How to fix date format in ASP .NET BoundField (DataFormatString)?

https://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.boundfield.dataformatstring(v=vs.110).aspx?cs-save-lang=1&cs-lang=csharp#code-snippet-1 


In The above link you will find the answer

**C or c**

    Displays numeric values in currency format. You can specify the number of decimal places.
    Example:

Format: {0:C}
123.456 -> $123.46

**D or d**

    Displays integer values in decimal format. You can specify the number of digits. (Although the type is referred to as "decimal", the numbers are formatted as integers.)
    Example:
        Format: {0:D}
    1234 -> 1234
    Format: {0:D6}
    1234 -> 001234

    **E or e**
    Displays numeric values in scientific (exponential) format. You can specify the number of decimal places.
    Example:
    Format: {0:E}
    1052.0329112756 -> 1.052033E+003
    Format: {0:E2}
    -1052.0329112756 -> -1.05e+003

**F or f**
Displays numeric values in fixed format. You can specify the number of decimal places.
Example:
Format: {0:F}
1234.567 -> 1234.57
Format: {0:F3}
1234.567 -> 1234.567

**G or g**
Displays numeric values in general format (the most compact of either fixed-point or scientific notation). You can specify the number of significant digits.
Example:
Format: {0:G}
-123.456 -> -123.456
Format: {0:G2}
-123.456 -> -120

F or f
Displays numeric values in fixed format. You can specify the number of decimal places.
Format: {0:F}
1234.567 -> 1234.57
Format: {0:F3}
1234.567 -> 1234.567

G or g
Displays numeric values in general format (the most compact of either fixed-point or scientific notation). You can specify the number of significant digits.
Format: {0:G}
-123.456 -> -123.456
Format: {0:G2}
-123.456 -> -120

N or n
Displays numeric values in number format (including group separators and optional negative sign). You can specify the number of decimal places.
Format: {0:N}
1234.567 -> 1,234.57
Format: {0:N4}
1234.567 -> 1,234.5670

P or p
Displays numeric values in percent format. You can specify the number of decimal places.
Format: {0:P}
1 -> 100.00%
Format: {0:P1}
.5 -> 50.0%

R or r
Displays Single, Double, or BigInteger values in round-trip format.
Format: {0:R}
123456789.12345678 -> 123456789.12345678

X or x
Displays integer values in hexadecimal format. You can specify the number of digits.
Format: {0:X}
255 -> FF
Format: {0:x4}
255 -> 00ff

Ruby on Rails: how to render a string as HTML?

You are mixing your business logic with your content. Instead, I'd recommend sending the data to your page and then using something like JQuery to place the data where you need it to go.

This has the advantage of keeping all your HTML in the HTML pages where it belongs so your web designers can modify the HTML later without having to pour through server side code.

Or if you're not wanting to use JavaScript, you could try this:

@str = "Hi"

<b><%= @str ></b>

At least this way your HTML is in the HTML page where it belongs.

How to include files outside of Docker's build context?

I believe the simpler workaround would be to change the 'context' itself.

So, for example, instead of giving:

docker build -t hello-demo-app .

which sets the current directory as the context, let's say you wanted the parent directory as the context, just use:

docker build -t hello-demo-app ..

Keeping ASP.NET Session Open / Alive

Whenever you make a request to the server the session timeout resets. So you can just make an ajax call to an empty HTTP handler on the server, but make sure the handler's cache is disabled, otherwise the browser will cache your handler and won't make a new request.

KeepSessionAlive.ashx.cs

public class KeepSessionAlive : IHttpHandler, IRequiresSessionState
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
            context.Response.Cache.SetExpires(DateTime.UtcNow.AddMinutes(-1));
            context.Response.Cache.SetNoStore();
            context.Response.Cache.SetNoServerCaching();
        }
    }

.JS:

window.onload = function () {
        setInterval("KeepSessionAlive()", 60000)
}

 function KeepSessionAlive() {
 url = "/KeepSessionAlive.ashx?";
        var xmlHttp = new XMLHttpRequest();
        xmlHttp.open("GET", url, true);
        xmlHttp.send();
        }

@veggerby - There is no need for the overhead of storing variables in the session. Just preforming a request to the server is enough.

postgres, ubuntu how to restart service on startup? get stuck on clustering after instance reboot

ENABLE is what you are looking for

USAGE: type this command once and then you are good to go. Your service will start automaticaly at boot up

 sudo systemctl enable postgresql

DISABLE exists as well ofc

Some DOC: freedesktop man systemctl

How to configure multi-module Maven + Sonar + JaCoCo to give merged coverage report?

I'll post my solution as it it subtly different from others and also took me a solid day to get right, with the assistance of the existing answers.

For a multi-module Maven project:

ROOT
|--WAR
|--LIB-1
|--LIB-2
|--TEST

Where the WAR project is the main web app, LIB 1 and 2 are additional modules the WAR depends on and TEST is where the integration tests live. TEST spins up an embedded Tomcat instance (not via Tomcat plugin) and runs WAR project and tests them via a set of JUnit tests. The WAR and LIB projects both have their own unit tests.

The result of all this is the integration and unit test coverage being separated and able to be distinguished in SonarQube.

ROOT pom.xml

<!-- Sonar properties-->
<sonar.jacoco.itReportPath>${project.basedir}/../target/jacoco-it.exec</sonar.jacoco.itReportPath>
<sonar.jacoco.reportPath>${project.basedir}/../target/jacoco.exec</sonar.jacoco.reportPath>
<sonar.language>java</sonar.language>
<sonar.java.coveragePlugin>jacoco</sonar.java.coveragePlugin>

<!-- build/plugins (not build/pluginManagement/plugins!) -->
<plugin>
    <groupId>org.jacoco</groupId>
    <artifactId>jacoco-maven-plugin</artifactId>
    <version>0.7.6.201602180812</version>
    <executions>
        <execution>
            <id>agent-for-ut</id>
            <goals>
                <goal>prepare-agent</goal>
            </goals>
            <configuration>
                <append>true</append>
                <destFile>${sonar.jacoco.reportPath}</destFile>
            </configuration>
        </execution>
        <execution>
            <id>agent-for-it</id>
            <goals>
                <goal>prepare-agent-integration</goal>
            </goals>
            <configuration>
                <append>true</append>
                <destFile>${sonar.jacoco.itReportPath}</destFile>
            </configuration>
        </execution>
    </executions>
</plugin>

WAR, LIB and TEST pom.xml will inherit the the JaCoCo plugins execution.

TEST pom.xml

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-failsafe-plugin</artifactId>
    <version>2.19.1</version>
    <executions>
        <execution>
            <goals>
                <goal>integration-test</goal>
                <goal>verify</goal>
            </goals>
            <configuration>
                <skipTests>${skip.tests}</skipTests>
                <argLine>${argLine} -Duser.timezone=UTC -Xms256m -Xmx256m</argLine>
                <includes>
                    <includes>**/*Test*</includes>
                </includes>
            </configuration>
        </execution>
    </executions>
</plugin>

I also found Petri Kainulainens blog post 'Creating Code Coverage Reports for Unit and Integration Tests With the JaCoCo Maven Plugin' to be valuable for the JaCoCo setup side of things.

React JS Error: is not defined react/jsx-no-undef

Strangely enough, the reason for my failure was about the CamelCase that I was applying to the component name. MyComponent was giving me this error but then I renamed it to Mycomponent and voila, it worked!!!

What's the difference between JavaScript and Java?

Don't be confused with name..
Java was created at Sun Microsystems (now Oracle).
But, JavaScript was created at Netscape (now Mozilla) in the early days of the Web, and technically, “Java-Script” is a trademark licensed from Sun Microsystems used to describe Netscape’s implementation of the language. Netscape submitted the language for standardization to ECMA (European Computer Manufacturer’s Association) and because of trademark issues, the standardized version of the language was stuck with the awkward name “ECMAScript.” For the same trademark reasons, Microsoft’s version of the language is formally known as “JScript.” In practice, just about everyone calls the language JavaScript. The real name is “ECMAScript”.

Both are fully different languages!!!

Cast IList to List

If you have an IList containing interfaces, you can cast it like this:

List to IList

List<Foo> Foos = new List<Foo>(); 
IList<IFoo> IFoos = Foos.ToList<IFoo>();

IList to List

IList<IFoo> IFoos = new List<IFoo>();
List<Foo> Foos = new List<Foo>(IFoos.Select(x => (Foo)x));

This assumes Foo has IFoo interfaced.

Asyncio.gather vs asyncio.wait

asyncio.wait is more low level than asyncio.gather.

As the name suggests, asyncio.gather mainly focuses on gathering the results. It waits on a bunch of futures and returns their results in a given order.

asyncio.wait just waits on the futures. And instead of giving you the results directly, it gives done and pending tasks. You have to manually collect the values.

Moreover, you could specify to wait for all futures to finish or just the first one with wait.

React JS onClick event handler

Here is how you define a react onClick event handler, which was answering the question title... using es6 syntax

import React, { Component } from 'react';

export default class Test extends Component {
  handleClick(e) {
    e.preventDefault()
    console.log(e.target)
  }

  render() {
    return (
      <a href='#' onClick={e => this.handleClick(e)}>click me</a>
    )
  }
}

Where is the visual studio HTML Designer?

Go to [Tools, Options], section "Web Forms Designer" and enable the option "Enable Web Forms Designer". That should give you the Design and Split option again.

Java: How to check if object is null?

if (yourObject instanceof yourClassName) will evaluate to false if yourObject is null.

ASP.NET MVC Razor: How to render a Razor Partial View's HTML inside the controller action

I saw that someone was wondering how to do it for another controller.

In my case I had all of my email templates in the Views/Email folder, but you could modify this to pass in the controller in which you have views associated for.

public static string RenderViewToString(Controller controller, string viewName, object model)
    {
        var oldController = controller.RouteData.Values["controller"].ToString();

        if (controller.GetType() != typeof(EmailController))
            controller.RouteData.Values["controller"] = "Email";

        var oldModel = controller.ViewData.Model;
        controller.ViewData.Model = model;
        try
        {
            using (var sw = new StringWriter())
            {
                var viewResult = ViewEngines.Engines.FindView(controller.ControllerContext, viewName,
                                                                           null);

                var viewContext = new ViewContext(controller.ControllerContext, viewResult.View, controller.ViewData, controller.TempData, sw);
                viewResult.View.Render(viewContext, sw);

                //Cleanup
                controller.ViewData.Model = oldModel;
                controller.RouteData.Values["controller"] = oldController;

                return sw.GetStringBuilder().ToString();
            }
        }
        catch (Exception ex)
        {
            Elmah.ErrorSignal.FromCurrentContext().Raise(ex);

            throw ex;
        }
    }

Essentially what this does is take a controller, such as AccountController and modify it to think it's an EmailController so that the code will look in the Views/Email folder. It's necessary to do this because the FindView method doesn't take a straight up path as a parameter, it wants a ControllerContext.

Once done rendering the string, it returns the AccountController back to its initial state to be used by the Response object.

How do I redirect a user when a button is clicked?

If, like me, you don't like to rely on JavaScript for links on buttons. You can also use a anchor and style it like your buttons using CSS.

<a href="/Controller/View" class="Button">Text</a>

Response.Redirect to new window

You can use this as extension method

public static class ResponseHelper
{ 
    public static void Redirect(this HttpResponse response, string url, string target, string windowFeatures) 
    { 

        if ((String.IsNullOrEmpty(target) || target.Equals("_self", StringComparison.OrdinalIgnoreCase)) && String.IsNullOrEmpty(windowFeatures)) 
        { 
            response.Redirect(url); 
        } 
        else 
        { 
            Page page = (Page)HttpContext.Current.Handler; 

            if (page == null) 
            { 
                throw new InvalidOperationException("Cannot redirect to new window outside Page context."); 
            } 
            url = page.ResolveClientUrl(url); 

            string script; 
            if (!String.IsNullOrEmpty(windowFeatures)) 
            { 
                script = @"window.open(""{0}"", ""{1}"", ""{2}"");"; 
            } 
            else 
            { 
                script = @"window.open(""{0}"", ""{1}"");"; 
            }
            script = String.Format(script, url, target, windowFeatures); 
            ScriptManager.RegisterStartupScript(page, typeof(Page), "Redirect", script, true); 
        } 
    }
}

With this you get nice override on the actual Response object

Response.Redirect(redirectURL, "_blank", "menubar=0,scrollbars=1,width=780,height=900,top=10");

Get element from within an iFrame

Above answers gave good solutions using Javscript. Here is a simple jQuery solution:

$('#iframeId').contents().find('div')

The trick here is jQuery's .contents() method, unlike .children() which can only get HTML elements, .contents() can get both text nodes and HTML elements. That's why one can get document contents of an iframe by using it.

Further reading about jQuery .contents(): .contents()

Note that the iframe and page have to be on the same domain.

How to copy to clipboard using Access/VBA?

VB 6 provides a Clipboard object that makes all of this extremely simple and convenient, but unfortunately that's not available from VBA.

If it were me, I'd go the API route. There's no reason to be scared of calling native APIs; the language provides you with the ability to do that for a reason.

However, a simpler alternative is to use the DataObject class, which is part of the Forms library. I would only recommend going this route if you are already using functionality from the Forms library in your app. Adding a reference to this library only to use the clipboard seems a bit silly.

For example, to place some text on the clipboard, you could use the following code:

Dim clipboard As MSForms.DataObject
Set clipboard = New MSForms.DataObject
clipboard.SetText "A string value"
clipboard.PutInClipboard

Or, to copy text from the clipboard into a string variable:

Dim clipboard As MSForms.DataObject
Dim strContents As String

Set clipboard = New MSForms.DataObject
clipboard.GetFromClipboard
strContents = clipboard.GetText

WPF Data Binding and Validation Rules Best Practices

From MS's Patterns & Practices documentation:

Data Validation and Error Reporting

Your view model or model will often be required to perform data validation and to signal any data validation errors to the view so that the user can act to correct them.

Silverlight and WPF provide support for managing data validation errors that occur when changing individual properties that are bound to controls in the view. For single properties that are data-bound to a control, the view model or model can signal a data validation error within the property setter by rejecting an incoming bad value and throwing an exception. If the ValidatesOnExceptions property on the data binding is true, the data binding engine in WPF and Silverlight will handle the exception and display a visual cue to the user that there is a data validation error.

However, throwing exceptions with properties in this way should be avoided where possible. An alternative approach is to implement the IDataErrorInfo or INotifyDataErrorInfo interfaces on your view model or model classes. These interfaces allow your view model or model to perform data validation for one or more property values and to return an error message to the view so that the user can be notified of the error.

The documentation goes on to explain how to implement IDataErrorInfo and INotifyDataErrorInfo.

Multiple INSERT statements vs. single INSERT with multiple VALUES

The issue probably has to do with the time it takes to compile the query.

If you want to speed up the inserts, what you really need to do is wrap them in a transaction:

BEGIN TRAN;
INSERT INTO T_TESTS (TestId, FirstName, LastName, Age) 
   VALUES ('6f3f7257-a3d8-4a78-b2e1-c9b767cfe1c1', 'First 0', 'Last 0', 0);
INSERT INTO T_TESTS (TestId, FirstName, LastName, Age) 
   VALUES ('32023304-2e55-4768-8e52-1ba589b82c8b', 'First 1', 'Last 1', 1);
...
INSERT INTO T_TESTS (TestId, FirstName, LastName, Age) 
   VALUES ('f34d95a7-90b1-4558-be10-6ceacd53e4c4', 'First 999', 'Last 999', 999);
COMMIT TRAN;

From C#, you might also consider using a table valued parameter. Issuing multiple commands in a single batch, by separating them with semicolons, is another approach that will also help.

Default string initialization: NULL or Empty?

+1 for distinguishing between "empty" and NULL. I agree that "empty" should mean "valid, but blank" and "NULL" should mean "invalid."

So I'd answer your question like this:

empty when I want a valid default value that may or may not be changed, for example, a user's middle name.

NULL when it is an error if the ensuing code does not set the value explicitly.

Cannot connect to Database server (mysql workbench)

Did you try to determine if this is a problem with Workbench or a general connection problem? Try this:

  1. Open a terminal
  2. Type mysql -u root -p -h 127.0.0.1 -P 3306
  3. If you can connect successfully you will see a mysql prompt after you type your password (type quit and Enter there to exit).

Report back how this worked.

how to get multiple checkbox value using jquery

Since u have the same class name against all check box, thus

   $(".ads_Checkbox") 

will give u all the checkboxes, and then you can iterate them using each loop like

$(".ads_Checkbox:checked").each(function(){
   alert($(this).val());
});

How to get year, month, day, hours, minutes, seconds and milliseconds of the current moment in Java?

Look at the API documentation for the java.util.Calendar class and its derivatives (you may be specifically interested in the GregorianCalendar class).

Display an image into windows forms

Here (http://www.dotnetperls.com/picturebox) there 3 ways to do this:

  • Like you are doing.
  • Using ImageLocation property of the PictureBox like:

    private void Form1_Load(object sender, EventArgs e)
    {
        PictureBox pb1 = new PictureBox();            
        pb1.ImageLocation = "../SamuderaJayaMotor.png";
        pb1.SizeMode = PictureBoxSizeMode.AutoSize;
    }
    
  • Using an image from the web like:

    private void Form1_Load(object sender, EventArgs e)
    {
        PictureBox pb1 = new PictureBox();            
        pb1.ImageLocation = "http://www.dotnetperls.com/favicon.ico";
        pb1.SizeMode = PictureBoxSizeMode.AutoSize;
    }
    

And please, be sure that "../SamuderaJayaMotor.png" is the correct path of the image that you are using.

How to get a jqGrid selected row cells value

yo have to declarate de vars...

var selectedRowId = $('#list').jqGrid ('getGridParam', 'selrow');
var columnName = $('#list').jqGrid('getCell', selectedRowId, 'columnName');

var nombre_img_articulo = $('#list').jqGrid('getCell', selectedRowId, 'img_articulo');

Twitter bootstrap progress bar animation on page load

EDIT

  • Class name changed from bar to progress-bar in v3.1.1

HTML

<div class="container">
    <div class="progress progress-striped active">
        <div class="bar" style="width: 0%;"></div>
    </div>
</div>?

CSS

@import url('http://twitter.github.com/bootstrap/assets/css/bootstrap.css');

.container {
    margin-top: 30px;
    width: 400px;
}?

jQuery used in the fiddle below and on the document.ready

$(document).ready(function(){

    var progress = setInterval(function() {
        var $bar = $('.bar');

        if ($bar.width()>=400) {
            clearInterval(progress);
            $('.progress').removeClass('active');
        } else {
            $bar.width($bar.width()+40);
        }
        $bar.text($bar.width()/4 + "%");
    }, 800);

});?

Demo

JSFiddle

Updated JSFiddle

How to refresh app upon shaking the device?

Here is an example code. Put this into your activity class:

  /* put this into your activity class */
  private SensorManager mSensorManager;
  private float mAccel; // acceleration apart from gravity
  private float mAccelCurrent; // current acceleration including gravity
  private float mAccelLast; // last acceleration including gravity

  private final SensorEventListener mSensorListener = new SensorEventListener() {

    public void onSensorChanged(SensorEvent se) {
      float x = se.values[0];
      float y = se.values[1];
      float z = se.values[2];
      mAccelLast = mAccelCurrent;
      mAccelCurrent = (float) Math.sqrt((double) (x*x + y*y + z*z));
      float delta = mAccelCurrent - mAccelLast;
      mAccel = mAccel * 0.9f + delta; // perform low-cut filter
    }

    public void onAccuracyChanged(Sensor sensor, int accuracy) {
    }
  };

  @Override
  protected void onResume() {
    super.onResume();
    mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
  }

  @Override
  protected void onPause() {
    mSensorManager.unregisterListener(mSensorListener);
    super.onPause();
  }

And add this to your onCreate method:

    /* do this in onCreate */
    mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
    mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
    mAccel = 0.00f;
    mAccelCurrent = SensorManager.GRAVITY_EARTH;
    mAccelLast = SensorManager.GRAVITY_EARTH;

You can then ask "mAccel" wherever you want in your application for the current acceleration, independent from the axis and cleaned from static acceleration such as gravity. It will be approx. 0 if there is no movement, and, lets say >2 if the device is shaked.

Based on the comments - to test this:

if (mAccel > 12) {
    Toast toast = Toast.makeText(getApplicationContext(), "Device has shaken.", Toast.LENGTH_LONG);
    toast.show();
}

Notes:

The accelometer should be deactivated onPause and activated onResume to save resources (CPU, Battery). The code assumes we are on planet Earth ;-) and initializes the acceleration to earth gravity. Otherwise you would get a strong "shake" when the application starts and "hits" the ground from free-fall. However, the code gets used to the gravitation due to the low-cut filter and would work also on other planets or in free space, once it is initialized. (you never know how long your application will be in use...;-)

Display a float with two decimal places in Python

If you want to get a floating point value with two decimal places limited at the time of calling input,

Check this out ~

a = eval(format(float(input()), '.2f'))   # if u feed 3.1415 for 'a'.
print(a)                                  # output 3.14 will be printed.

Should I test private methods or only public ones?

What is the purpose of testing?

The majority of the answers so far are saying that private methods are implementation details which don't (or at least shouldn't) matter so long as the public interface is well-tested and working. That's absolutely correct if your only purpose for testing is to guarantee that the public interface works.

Personally, my primary use for code tests is to ensure that future code changes don't cause problems and to aid my debugging efforts if they do. I find that testing the private methods just as thoroughly as the public interface (if not more so!) furthers that purpose.

Consider: You have public method A which calls private method B. A and B both make use of method C. C is changed (perhaps by you, perhaps by a vendor), causing A to start failing its tests. Wouldn't it be useful to have tests for B also, even though it's private, so that you know whether the problem is in A's use of C, B's use of C, or both?

Testing private methods also adds value in cases where test coverage of the public interface is incomplete. While this is a situation we generally want to avoid, the efficiency unit testing depends both on the tests finding bugs and the associated development and maintenance costs of those tests. In some cases, the benefits of 100% test coverage may be judged insufficient to warrant the costs of those tests, producing gaps in the public interface's test coverage. In such cases, a well-targeted test of a private method can be a very effective addition to the code base.

Reading a UTF8 CSV file with Python

The link to the help page is the same for python 2.6 and as far as I know there was no change in the csv module since 2.5 (besides bug fixes). Here is the code that just works without any encoding/decoding (file da.csv contains the same data as the variable data). I assume that your file should be read correctly without any conversions.

test.py:

## -*- coding: utf-8 -*-
#
# NOTE: this first line is important for the version b) read from a string(unicode) variable
#

import csv

data = \
"""0665000FS10120684,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Bleu
0665000FS10120689,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Gris
0665000FS10120687,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Vert"""

# a) read from a file
print 'reading from a file:'
for (f1, f2, f3) in csv.reader(open('da.csv'), dialect=csv.excel):
    print (f1, f2, f3)

# b) read from a string(unicode) variable
print 'reading from a list of strings:'
reader = csv.reader(data.split('\n'), dialect=csv.excel)
for (f1, f2, f3) in reader:
    print (f1, f2, f3)

da.csv:

0665000FS10120684,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Bleu
0665000FS10120689,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Gris
0665000FS10120687,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Vert

Display Parameter(Multi-value) in Report

Hopefully someone else finds this useful:

Using the Join is the best way to use a multi-value parameter. But what if you want to have an efficient 'Select All'? If there are 100s+ then the query will be very inefficient.

To solve this instead of using a SQL Query as is, change it to using an expression (click the Fx button top right) then build your query something like this (speech marks are necessary):

= "Select * from tProducts Where 1 = 1 " 
IIF(Parameters!ProductID.Value(0)=-1,Nothing," And ProductID In (" & Join(Parameters!ProductID.Value,"','") & ")")

In your Parameter do the following:

    SELECT -1 As ProductID, 'All' as ProductName Union All
    Select  
    tProducts.ProductID,tProducts.ProductName
    FROM
    tProducts

By building the query as an expression means you can make the SQL Statement more efficient but also handle the difficulty SQL Server has with handling values in an 'In' statement.

PostgreSQL Exception Handling

Just want to add my two cents on this old post:

In my opinion, almost all of relational database engines include a commit transaction execution automatically after execute a DDL command even when you have autocommit=false, So you don't need to start a transaction to avoid a potential truncated object creation because It is completely unnecessary.

RecyclerView expand/collapse items

There is simply no need of using third party libraries. A little tweak in the method demonstrated in Google I/O 2016 and Heisenberg on this topic, does the trick.

Since notifyDataSetChanged() redraws the complete RecyclerView, notifyDataItemChanged() is a better option (not the best) because we have the position and the ViewHolder at our disposal, and notifyDataItemChanged() only redraws the particular ViewHolder at a given position.

But the problem is that the premature disappearence of the ViewHolder upon clicking and it's emergence is not eliminated even if notifyDataItemChanged() is used.

The following code does not resort to notifyDataSetChanged() or notifyDataItemChanged() and is Tested on API 23 and works like a charm when used on a RecyclerView where each ViewHolder has a CardView as it's root element:

holder.itemView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            final boolean visibility = holder.details.getVisibility()==View.VISIBLE;

            if (!visibility)
            {
                holder.itemView.setActivated(true);
                holder.details.setVisibility(View.VISIBLE);
                if (prev_expanded!=-1 && prev_expanded!=position)
                {
                    recycler.findViewHolderForLayoutPosition(prev_expanded).itemView.setActivated(false);
                    recycler.findViewHolderForLayoutPosition(prev_expanded).itemView.findViewById(R.id.cpl_details).setVisibility(View.GONE);
                }
                prev_expanded = position;
            }
            else
            {
                holder.itemView.setActivated(false);
                holder.details.setVisibility(View.GONE);
            }
            TransitionManager.beginDelayedTransition(recycler);              
        }
});

prev_position is an global integer initialized to -1. details is the complete view which is shown when expanded and cloaked when collapsed.

As said, the root element of ViewHolder is a CardView with foreground and stateListAnimator attributes defined exactly as said by Heisenberg on this topic.

UPDATE: The above demonstration will collapse previosuly expanded item if one of them in expanded. To modify this behaviour and keep the an expanded item as it is even when another item is expanded, you'll need the following code.

if (row.details.getVisibility()!=View.VISIBLE)
    {
        row.details.setVisibility(View.VISIBLE);
        row.root.setActivated(true);
        row.details.animate().alpha(1).setStartDelay(500);
    }
    else
    {
        row.root.setActivated(false);
        row.details.setVisibility(View.GONE);
        row.details.setAlpha(0);
    }
    TransitionManager.beginDelayedTransition(recycler);

UPDATE: When expanding the last items on the list, it may not be brought into full visibility because the expanded portion goes below the screen. To get the full item within screen use the following code.

LinearLayoutManager manager = (LinearLayoutManager) recycler.getLayoutManager();
    int distance;
    View first = recycler.getChildAt(0);
    int height = first.getHeight();
    int current = recycler.getChildAdapterPosition(first);
    int p = Math.abs(position - current);
    if (p > 5) distance = (p - (p - 5)) * height;
    else       distance = p * height;
    manager.scrollToPositionWithOffset(position, distance);

IMPORTANT: For the above demonstrations to work, one must keep in their code an instance of the RecyclerView & it's LayoutManager (the later for flexibility)

How to strip HTML tags from string in JavaScript?

Using the browser's parser is the probably the best bet in current browsers. The following will work, with the following caveats:

  • Your HTML is valid within a <div> element. HTML contained within <body> or <html> or <head> tags is not valid within a <div> and may therefore not be parsed correctly.
  • textContent (the DOM standard property) and innerText (non-standard) properties are not identical. For example, textContent will include text within a <script> element while innerText will not (in most browsers). This only affects IE <=8, which is the only major browser not to support textContent.
  • The HTML does not contain <script> elements.
  • The HTML is not null
  • The HTML comes from a trusted source. Using this with arbitrary HTML allows arbitrary untrusted JavaScript to be executed. This example is from a comment by Mike Samuel on the duplicate question: <img onerror='alert(\"could run arbitrary JS here\")' src=bogus>

Code:

var html = "<p>Some HTML</p>";
var div = document.createElement("div");
div.innerHTML = html;
var text = div.textContent || div.innerText || "";

How can I programmatically get the MAC address of an iphone

A lot of these questions only address the Mac address. If you also require the IP address I just wrote this, may need some work but seems to work well on my machine...

- (NSString *)getLocalIPAddress
{
    NSArray *ipAddresses = [[NSHost currentHost] addresses];
    NSArray *sortedIPAddresses = [ipAddresses sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];

    NSNumberFormatter *numberFormatter = [[NSNumberFormatter alloc] init];
    numberFormatter.allowsFloats = NO;

    for (NSString *potentialIPAddress in sortedIPAddresses)
    {
        if ([potentialIPAddress isEqualToString:@"127.0.0.1"]) {
            continue;
        }

        NSArray *ipParts = [potentialIPAddress componentsSeparatedByString:@"."];

        BOOL isMatch = YES;

        for (NSString *ipPart in ipParts) {
            if (![numberFormatter numberFromString:ipPart]) {
                isMatch = NO;
                break;
            }
        }
        if (isMatch) {
            return potentialIPAddress;
        }
    }

    // No IP found
    return @"?.?.?.?";
}

How to use "like" and "not like" in SQL MSAccess for the same field?

If you're doing it in VBA (and not in a query) then: where field like "AA" and field not like "BB" then would not work.

You'd have to use: where field like "AA" and field like "BB" = false then

Appropriate datatype for holding percent values?

Use numeric(n,n) where n has enough resolution to round to 1.00. For instance:

declare @discount numeric(9,9)
    , @quantity int
select @discount = 0.999999999
    , @quantity = 10000

select convert(money, @discount * @quantity)

Get the Id of current table row with Jquery

Your code would be more like so:

$('tr input[type=button]').click(function(){
    id = $(this).closest('tr').attr('id');
});

How to show hidden divs on mouseover?

There is a really simple way to do this in a CSS only way.

Apply an opacity to 0, therefore making it invisible, but it will still react to JavaScript events and CSS selectors. In the hover selector, make it visible by changing the opacity value.

_x000D_
_x000D_
#mouse_over {_x000D_
  opacity: 0;_x000D_
}_x000D_
_x000D_
#mouse_over:hover {_x000D_
  opacity: 1;_x000D_
}
_x000D_
<div style='border: 5px solid black; width: 120px; font-family: sans-serif'>_x000D_
<div style='height: 20px; width: 120px; background-color: cyan;' id='mouse_over'>Now you see me</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to get all options of a select using jQuery?

I don't know jQuery, but I do know that if you get the select element, it contains an 'options' object.

var myOpts = document.getElementById('yourselect').options;
alert(myOpts[0].value) //=> Value of the first option

how to call service method from ng-change of select in angularjs?

You have at least two issues in your code:

  • ng-change="getScoreData(Score)

    Angular doesn't see getScoreData method that refers to defined service

  • getScoreData: function (Score, callback)

    We don't need to use callback since GET returns promise. Use then instead.

Here is a working example (I used random address only for simulation):

HTML

<select ng-model="score"
        ng-change="getScoreData(score)" 
        ng-options="score as score.name for score in  scores"></select>
    <pre>{{ScoreData|json}}</pre> 

JS

var fessmodule = angular.module('myModule', ['ngResource']);

fessmodule.controller('fessCntrl', function($scope, ScoreDataService) {

    $scope.scores = [{
        name: 'Bukit Batok Street 1',
        URL: 'http://maps.googleapis.com/maps/api/geocode/json?address=Singapore, SG, Singapore, 153 Bukit Batok Street 1&sensor=true'
    }, {
        name: 'London 8',
        URL: 'http://maps.googleapis.com/maps/api/geocode/json?address=Singapore, SG, Singapore, London 8&sensor=true'
    }];

    $scope.getScoreData = function(score) {
        ScoreDataService.getScoreData(score).then(function(result) {
            $scope.ScoreData = result;
        }, function(result) {
            alert("Error: No data returned");
        });
    };

});

fessmodule.$inject = ['$scope', 'ScoreDataService'];

fessmodule.factory('ScoreDataService', ['$http', '$q', function($http) {

    var factory = {
        getScoreData: function(score) {
            console.log(score);
            var data = $http({
                method: 'GET',
                url: score.URL
            });


            return data;
        }
    }
    return factory;
}]);

Demo Fiddle

Debugging with command-line parameters in Visual Studio

Even if you do start the executable outside Visual Studio, you can still use the "Attach" command to connect Visual Studio to your already-running executable. This can be useful e.g. when your application is run as a plug-in within another application.

ImportError: No module named xlsxwriter

I am not sure what caused this but it went all well once I changed the path name from Lib into lib and I was finally able to make it work.

Java Scanner class reading strings

This because in.nextInt() only receive a int number, doesn't receive a new line. So you input 3 and press "Enter", the end of line is read by in.nextline().

Here is my code:

int nnames;
String names[];

System.out.print("How many names are you going to save: ");
Scanner in = new Scanner(System.in);
nnames = in.nextInt();
in.nextLine();
names = new String[nnames];

for (int i = 0; i < names.length; i++){
        System.out.print("Type a name: ");
        names[i] = in.nextLine();
}

Measuring text height to be drawn on Canvas ( Android )

The height is the text size you have set on the Paint variable.

Another way to find out the height is

mPaint.getTextSize();

Returning JSON response from Servlet to Javascript/JSP page

I used JSONObject as shown below in Servlet.

    JSONObject jsonReturn = new JSONObject();

    NhAdminTree = AdminTasks.GetNeighborhoodTreeForNhAdministrator( connection, bwcon, userName);

    map = new HashMap<String, String>();
    map.put("Status", "Success");
    map.put("FailureReason", "None");
    map.put("DataElements", "2");

    jsonReturn = new JSONObject();
    jsonReturn.accumulate("Header", map);

    List<String> list = new ArrayList<String>();
    list.add(NhAdminTree);
    list.add(userName);

    jsonReturn.accumulate("Elements", list);

The Servlet returns this JSON object as shown below:

    response.setContentType("application/json");
    response.getWriter().write(jsonReturn.toString());

This Servlet is called from Browser using AngularJs as below

$scope.GetNeighborhoodTreeUsingPost = function(){
    alert("Clicked GetNeighborhoodTreeUsingPost : " + $scope.userName );

    $http({

        method: 'POST',
        url : 'http://localhost:8080/EPortal/xlEPortalService',
        headers: {
           'Content-Type': 'application/json'
         },
        data : {
            'action': 64,
            'userName' : $scope.userName
        }
    }).success(function(data, status, headers, config){
        alert("DATA.header.status : " + data.Header.Status);
        alert("DATA.header.FailureReason : " + data.Header.FailureReason);
        alert("DATA.header.DataElements : " + data.Header.DataElements);
        alert("DATA.elements : " + data.Elements);

    }).error(function(data, status, headers, config) {
        alert(data + " : " + status + " : " + headers + " : " + config);
    });

};

This code worked and it is showing correct data in alert dialog box:

Data.header.status : Success

Data.header.FailureReason : None

Data.header.DetailElements : 2

Data.Elements : Coma seperated string values i.e. NhAdminTree, userName

MySQL foreign key constraints, cascade delete

I think (I'm not certain) that foreign key constraints won't do precisely what you want given your table design. Perhaps the best thing to do is to define a stored procedure that will delete a category the way you want, and then call that procedure whenever you want to delete a category.

CREATE PROCEDURE `DeleteCategory` (IN category_ID INT)
LANGUAGE SQL
NOT DETERMINISTIC
MODIFIES SQL DATA
SQL SECURITY DEFINER
BEGIN

DELETE FROM
    `products`
WHERE
    `id` IN (
        SELECT `products_id`
        FROM `categories_products`
        WHERE `categories_id` = category_ID
    )
;

DELETE FROM `categories`
WHERE `id` = category_ID;

END

You also need to add the following foreign key constraints to the linking table:

ALTER TABLE `categories_products` ADD
    CONSTRAINT `Constr_categoriesproducts_categories_fk`
    FOREIGN KEY `categories_fk` (`categories_id`) REFERENCES `categories` (`id`)
    ON DELETE CASCADE ON UPDATE CASCADE,
    CONSTRAINT `Constr_categoriesproducts_products_fk`
    FOREIGN KEY `products_fk` (`products_id`) REFERENCES `products` (`id`)
    ON DELETE CASCADE ON UPDATE CASCADE

The CONSTRAINT clause can, of course, also appear in the CREATE TABLE statement.

Having created these schema objects, you can delete a category and get the behaviour you want by issuing CALL DeleteCategory(category_ID) (where category_ID is the category to be deleted), and it will behave how you want. But don't issue a normal DELETE FROM query, unless you want more standard behaviour (i.e. delete from the linking table only, and leave the products table alone).

Hadoop: «ERROR : JAVA_HOME is not set»

You should set JAVA_HOME in the hadoop-env.sh file also which is in the Hadoop configuration directory. By default the JAVA_HOME setting line is commented.

PHP Fatal error: Using $this when not in object context

You are calling a non-static method :

public function foobarfunc() {
    return $this->foo();
}

Using a static-call :

foobar::foobarfunc();

When using a static-call, the function will be called (even if not declared as static), but, as there is no instance of an object, there is no $this.

So :

  • You should not use static calls for non-static methods
  • Your static methods (or statically-called methods) can't use $this, which normally points to the current instance of the class, as there is no class instance when you're using static-calls.


Here, the methods of your class are using the current instance of the class, as they need to access the $foo property of the class.

This means your methods need an instance of the class -- which means they cannot be static.

This means you shouldn't use static calls : you should instanciate the class, and use the object to call the methods, like you did in your last portion of code :

$foobar = new foobar();
$foobar->foobarfunc();


For more informations, don't hesitate to read, in the PHP manual :


Also note that you probably don't need this line in your __construct method :

global $foo;

Using the global keyword will make the $foo variable, declared outside of all functions and classes, visibile from inside that method... And you probably don't have such a $foo variable.

To access the $foo class-property, you only need to use $this->foo, like you did.

Converting an OpenCV Image to Black and White

Here's a two line code I found online that might be helpful for a beginner

# Absolute value of the 32/64
abs_image_in32_64 = np.absolute(image_in32_64)

image_8U = np.uint8(abs_image_in32_64)

How do I change the select box arrow

You can skip the container or background image with pure css arrow:

select {

  /* make arrow and background */

  background:
    linear-gradient(45deg, transparent 50%, blue 50%),
    linear-gradient(135deg, blue 50%, transparent 50%),
    linear-gradient(to right, skyblue, skyblue);
  background-position:
    calc(100% - 21px) calc(1em + 2px),
    calc(100% - 16px) calc(1em + 2px),
    100% 0;
  background-size:
    5px 5px,
    5px 5px,
    2.5em 2.5em;
  background-repeat: no-repeat;

  /* styling and reset */

  border: thin solid blue;
  font: 300 1em/100% "Helvetica Neue", Arial, sans-serif;
  line-height: 1.5em;
  padding: 0.5em 3.5em 0.5em 1em;

  /* reset */

  border-radius: 0;
  margin: 0;      
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
  -webkit-appearance:none;
  -moz-appearance:none;
}

Sample here

Connect to SQL Server Database from PowerShell

I did remove integrated security ... my goal is to log onto a sql server using a connection string WITH active directory username / password. When I do that it always fails. Does not matter the format ... sam company\user ... upn [email protected] ... basic username.

New Line Issue when copying data from SQL Server 2012 to Excel

Once Data is exported to excel, highlight the date column and format to fit your needs or use the custom field. Worked for me like a charm!

Differences between JDK and Java SDK

Best example for this Question, SDK - Software Development Kit - Ex: Netbeans JDK - Java Development Kit.(This is Java compiler). Without JDK, we unable to run java programs in SDK.

How to solve SyntaxError on autogenerated manage.py?

Have you entered the virtual environment for django? Run python -m venv myvenv if you have not yet installed.

Deleting a local branch with Git

If you have created multiple worktrees with git worktree, you'll need to run git prune before you can delete the branch

babel-loader jsx SyntaxError: Unexpected token

The following way has helped me (includes react-hot, babel loaders and es2015, react presets):

loaders: [
      {
        test: /\.jsx?$/,
        exclude: /node_modules/,
        loaders: ['react-hot', 'babel?presets[]=es2015&presets[]=react']
      }
]

Show div #id on click with jQuery

This is simple way to Display Div using:-

$("#musicinfo").show();  //or
$("#musicinfo").css({'display':'block'});  //or
$("#musicinfo").toggle("slow");   //or
$("#musicinfo").fadeToggle();    //or

CSS/Javascript to force html table row on a single line

This trick here is using the esoteric table-layout:fixed rule

This CSS ought to work against your sample HTML:

table {table-layout:fixed}
td {overflow:hidden; white-space:nowrap}

You also ought to specify explicit column widths for the <td>s.

The table-layout:fixed rule says "The cell widths of this table depend on what I say, not on the actual content in the cells". This is useful normally because the browser can begin displaying the table after it has received the first <tr>. Otherwise, the browser has to receive the entire table before it can compute the column widths.

Laravel Advanced Wheres how to pass variable into function?

You can pass the necessary variables from the parent scope into the closure with the use keyword.

For example:

DB::table('users')->where(function ($query) use ($activated) {
    $query->where('activated', '=', $activated);
})->get();

More on that here.

EDIT (2019 update):

PHP 7.4 (will be released at November 28, 2019) introduces a shorter variation of the anonymous functions called arrow functions which makes this a bit less verbose.

An example using PHP 7.4 which is functionally nearly equivalent (see the 3rd bullet point below):

DB::table('users')->where(fn($query) => $query->where('activated', '=', $activated))->get();

Differences compared to the regular syntax:

  • fn keyword instead of function.
  • No need to explicitly list all variables which should be captured from the parent scope - this is now done automatically by-value. See the lack of use keyword in the latter example.
  • Arrow functions always return a value. This also means that it's impossible to use void return type when declaring them.
  • The return keyword must be omitted.
  • Arrow functions must have a single expression which is the return statement. Multi-line functions aren't supported at the moment. You can still chain methods though.

CSS Custom Dropdown Select that works across all browsers IE7+ FF Webkit

The pointer-events could be useful for this problem as you would be able to put a div over the arrow button, but still be able to click the arrow button.

The pointer-events css makes it possible to click through a div.

This approach will not work for IE versions older than IE11, however. You could something working in IE8 and IE9 if the element you put on top of the arrow button is an SVG element, but it will be more complicated to style the button the way you want proceeding like this.

Here a Js fiddle example: http://jsfiddle.net/e7qnqzx6/2/

Save and retrieve image (binary) from SQL Server using Entity Framework 6

Convert the image to a byte[] and store that in the database.


Add this column to your model:

public byte[] Content { get; set; }

Then convert your image to a byte array and store that like you would any other data:

public byte[] ImageToByteArray(System.Drawing.Image imageIn)
{
    using(var ms = new MemoryStream())
    {
        imageIn.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);

        return ms.ToArray();
    }
}

public Image ByteArrayToImage(byte[] byteArrayIn)
{
     using(var ms = new MemoryStream(byteArrayIn))
     {
         var returnImage = Image.FromStream(ms);

         return returnImage;
     }
}

Source: Fastest way to convert Image to Byte array

var image = new ImageEntity()
{
   Content = ImageToByteArray(image)
};

_context.Images.Add(image);
_context.SaveChanges();

When you want to get the image back, get the byte array from the database and use the ByteArrayToImage and do what you wish with the Image

This stops working when the byte[] gets to big. It will work for files under 100Mb

c# open a new form then close the current form?

This code may help you:

Master frm = new Master();

this.Hide();

frm.ShowDialog();

this.Close();

Get nth character of a string in Swift programming language

In Swift 3 without extensions to the String class, as simple as I can make it!

let myString = "abcedfg"
let characterLocationIndex = myString.index(myString.startIndex, offsetBy: 3)
let myCharacter = myString[characterLocationIndex]

myCharacter is "3" in this example.

Better way to find control in ASP.NET

https://blog.codinghorror.com/recursive-pagefindcontrol/

Page.FindControl("DataList1:_ctl0:TextBox3");

OR

private Control FindControlRecursive(Control root, string id)
{
    if (root.ID == id)
    {
        return root;
    }
    foreach (Control c in root.Controls)
    {
        Control t = FindControlRecursive(c, id);
        if (t != null)
        {
            return t;
        }
    }
    return null;
}

Cannot stop or restart a docker container

Check if there is any zombie process using "top" command.

docker ps | grep <<container name>> 

Get the container id.

ps -ef | grep <<container id>>

ps -ef|grep defunct | grep java

And kill the container by Parent PID .

What’s the difference between "Array()" and "[]" while declaring a JavaScript array?

There's more to this than meets the eye. Most other answers are correct BUT ALSO..

new Array(n)

  • Allows engine to reallocates space for n elements
  • Optimized for array creation
  • Created array is marked sparse which has the least performant array operations, that's because each index access has to check bounds, see if value exists and walk the prototype chain
  • If array is marked as sparse, there's no way back (at least in V8), it'll always be slower during its lifetime, even if you fill it up with content (packed array) 1ms or 2 hours later, doesn't matter

[1, 2, 3] || []

  • Created array is marked packed (unless you use delete or [1,,3] syntax)
  • Optimized for array operations (for .., forEach, map, etc)
  • Engine needs to reallocate space as the array grows

This probably isn't the case for older browser versions/browsers.

How to make EditText not editable through XML in Android?

Please try this!, it may help some people

<EditText  
android:enabled="false"
android:textColor="#000000"/>

Start new Activity and finish current one in Android?

FLAG_ACTIVITY_NO_HISTORY when starting the activity you wish to finish after the user goes to another one.

http://developer.android.com/reference/android/content/Intent.html#FLAG%5FACTIVITY%5FNO%5FHISTORY

What does ==$0 (double equals dollar zero) mean in Chrome Developer Tools?

It's the last selected DOM node index. Chrome assigns an index to each DOM node you select. So $0 will always point to the last node you selected, while $1 will point to the node you selected before that. Think of it like a stack of most recently selected nodes.

As an example, consider the following

<div id="sunday"></div>
<div id="monday"></div>
<div id="tuesday"></div>

Now you opened the devtools console and selected #sunday, #monday and #tuesday in the mentioned order, you will get ids like:

$0 -> <div id="tuesday"></div> 
$1 -> <div id="monday"></div>
$2 -> <div id="sunday"></div>

Note: It Might be useful to know that the node is selectable in your scripts (or console), for example one popular use for this is angular element selector, so you can simply pick your node, and run this:

angular.element($0).scope()

Voila you got access to node scope via console.

how to insert a new line character in a string to PrintStream then use a scanner to re-read the file

The linefeed character \n is not the line separator in certain operating systems (such as windows, where it's "\r\n") - my suggestion is that you use \r\n instead, then it'll both see the line-break with only \n and \r\n, I've never had any problems using it.

Also, you should look into using a StringBuilder instead of concatenating the String in the while-loop at BookCatalog.toString(), it is a lot more effective. For instance:

public String toString() {
        BookNode current = front;
        StringBuilder sb = new StringBuilder();
        while (current!=null){
            sb.append(current.getData().toString()+"\r\n ");
            current = current.getNext();
        }
        return sb.toString();
}

How to add to an existing hash in Ruby

x = {:ca => "Canada", :us => "United States"}
x[:de] = "Germany"
p x

How to hide the bar at the top of "youtube" even when mouse hovers over it?

Since YouTube has deprecated the showinfo parameter you can trick the player. Youtube will always try to center its video but logo, title, watch later button etc.. will always stay at the left and right side respectively.

So what you can do is put your Youtube iframe inside some div:

<div class="frame-container">
   <iframe></iframe>
</div>

Then you can increase the size of frame-container to be out of browser window, while aligning it so that the iframe video comes to the center. Example:

.frame-container {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 */  
    padding-top: 25px;
    width: 300%; /* enlarge beyond browser width */
    left: -100%; /* center */
}

.frame-container iframe {
    position: absolute; 
    top: 0; 
    left: 0; 
    width: 100%; 
    height: 100%;
}

Finnaly put everything inside a wrapper div to prevent page stretching due to 300% width:

<div class="wrapper">
   <div class="frame-container">
      <iframe></iframe>
   </div>
</div>

.wrapper {
   overflow: hidden;
   max-width: 100%;
}

Convert ASCII TO UTF-8 Encoding

If you know for sure that your current encoding is pure ASCII, then you don't have to do anything because ASCII is already a valid UTF-8.

But if you still want to convert, just to be sure that its UTF-8, then you can use iconv

$string = iconv('ASCII', 'UTF-8//IGNORE', $string);

The IGNORE will discard any invalid characters just in case some were not valid ASCII.

How does System.out.print() work?

It is a very sensitive point to understand how to work System.out.print. If the first element is String then plus(+) operator works as String concate operator. If the first element is integer plus(+) operator works as mathematical operator.

public static void main(String args[]) {
    System.out.println("String" + 8 + 8); //String88
    System.out.println(8 + 8+ "String"); //16String
}

How to delete file from public folder in laravel 5.1

Using PHP unlink() function, will have the file deleted

$path = public_path()."/uploads/".$from_db->image_name;
unlink($path);

The above will delete an image returned by $from_db->image_name located at public/uploads folder

Add an image in a WPF button

In the case of a 'missing' image there are several things to consider:

  1. When XAML can't locate a resource it might ignore it (when it won't throw a XamlParseException)

  2. The resource must be properly added and defined:

    • Make sure it exists in your project where expected.

    • Make sure it is built with your project as a resource.

      (Right click ? Properties ? BuildAction='Resource')

Snippet

Another thing to try in similar cases, which is also useful for reusing of the image (or any other resource):

Define your image as a resource in your XAML:

<UserControl.Resources>
     <Image x:Key="MyImage" Source.../>
</UserControl.Resources>

And later use it in your desired control(s):

<Button Content="{StaticResource MyImage}" />

Call a method of a controller from another controller using 'scope' in AngularJS

The best approach for you to communicate between the two controllers is to use events.

Scope Documentation

In this check out $on, $broadcast and $emit.

In general use case the usage of angular.element(catapp).scope() was designed for use outside the angular controllers, like within jquery events.

Ideally in your usage you would write an event in controller 1 as:

$scope.$on("myEvent", function (event, args) {
   $scope.rest_id = args.username;
   $scope.getMainCategories();
});

And in the second controller you'd just do

$scope.initRestId = function(){
   $scope.$broadcast("myEvent", {username: $scope.user.username });
};

Edit: Realised it was communication between two modules

Can you try including the firstApp module as a dependency to the secondApp where you declare the angular.module. That way you can communicate to the other app.

AngularJs directive not updating another directive's scope

Just wondering why you are using 2 directives?

It seems like, in this case it would be more straightforward to have a controller as the parent - handle adding the data from your service to its $scope, and pass the model you need from there into your warrantyDirective.

Or for that matter, you could use 0 directives to achieve the same result. (ie. move all functionality out of the separate directives and into a single controller).

It doesn't look like you're doing any explicit DOM transformation here, so in this case, perhaps using 2 directives is overcomplicating things.

Alternatively, have a look at the Angular documentation for directives: http://docs.angularjs.org/guide/directive The very last example at the bottom of the page explains how to wire up dependent directives.

An invalid form control with name='' is not focusable

For other AngularJS 1.x users out there, this error appeared because I was hiding a form control from displaying instead of removing it from the DOM entirely when I didn't need the control to be completed.

I fixed this by using ng-if instead of ng-show/ng-hide on the div containing the form control requiring validation.

Hope this helps you fellow edge case users.

Generics/templates in python?

If you using Python 2 or want to rewrite java code. Their is not real solution for this. Here is what I get working in a night: https://github.com/FlorianSteenbuck/python-generics I still get no compiler so you currently using it like that:

class A(GenericObject):
    def __init__(self, *args, **kwargs):
        GenericObject.__init__(self, [
            ['b',extends,int],
            ['a',extends,str],
            [0,extends,bool],
            ['T',extends,float]
        ], *args, **kwargs)

    def _init(self, c, a, b):
        print "success c="+str(c)+" a="+str(a)+" b="+str(b)

TODOs

  • Compiler
  • Get Generic Classes and Types working (For things like <? extends List<Number>>)
  • Add super support
  • Add ? support
  • Code Clean Up

Refused to load the font 'data:font/woff.....'it violates the following Content Security Policy directive: "default-src 'self'". Note that 'font-src'

I also faced the same issue today in my running code. Well, I found a lot of answers here. But the important thing I want to mention is that this error message is quite ambiguous and doesn't explicitly point out the exact error.

Some faced it due to browser extensions, some due to incorrect URL patterns and I faced this due to an error in my formGroup instance used in a pop-up in that screen. So, I would suggest everyone that before making any new changes in your code, please debug your code and verify that you don't have any such errors. You will certainly find the actual reason by debugging.

If nothing else works then check your URL as that is the most common reason for this issue.

How in node to split string by newline ('\n')?

It looks like regex /\r\n|\r|\n/ handles CR, LF, and CRLF line endings, their mixed sequences, and keeps all the empty lines inbetween. Try that!

_x000D_
_x000D_
    function splitLines(t) { return t.split(/\r\n|\r|\n/); }

    // single newlines
    console.log(splitLines("AAA\rBBB\nCCC\r\nDDD"));
    // double newlines
    console.log(splitLines("EEE\r\rFFF\n\nGGG\r\n\r\nHHH"));
    // mixed sequences
    console.log(splitLines("III\n\r\nJJJ\r\r\nKKK\r\n\nLLL\r\n\rMMM"));
_x000D_
_x000D_
_x000D_

You should get these arrays as a result:

[ "AAA", "BBB", "CCC", "DDD" ]
[ "EEE", "", "FFF", "", "GGG", "", "HHH" ]
[ "III", "", "JJJ", "", "KKK", "", "LLL", "", "MMM" ]

You can also teach that regex to recognize other legit Unicode line terminators by adding |\xHH or |\uHHHH parts, where H's are hexadecimal digits of the additional terminator character codepoint (as seen in Wikipedia article as U+HHHH).

Get current location of user in Android without using GPS or internet

No, you cannot currently get location without using GPS or internet.

Location techniques based on WiFi, Cellular, or Bluetooth work with the help of a large database that is constantly being updated. A device scans for transmitter IDs and then sends these in a query through the internet to a service such as Google, Apple, or Skyhook. That service responds with a location based on previous wireless surveys from known locations. Without internet access, you have to have a local copy of such a database and keep this up to date. For global usage, this is very impractical.

Theoretically, a mobile provider could provide local data service only but no access to the internet, and then answer location queries from mobile devices. Mobile providers don't do this; no one wants to pay for this kind of restricted data access. If you have data service through your mobile provider, then you have internet access.

In short, using LocationManager.NETWORK_PROVIDER or android.hardware.location.network to get location requires use of the internet.

Using the last known position requires you to have had GPS or internet access very recently. If you just had internet, presumably you can adjust your position or settings to get internet again. If your device has not had GPS or internet access, the last known position feature will not help you.

Without GPS or internet, you could:

  1. Take pictures of the night sky and use the current time to estimate your location based on a star chart. This would probably require additional equipment to ensure that the angles for your pictures are correctly measured.
  2. Use an accelerometer to track location starting from a known position. The accumulation of error in this kind of approach makes it impractical for most situations.

How to create a box when mouse over text in pure CSS?

You can also do it by toggling between display: block on hover and display:none without hover to produce the effect.

Delete multiple objects in django

You can delete any QuerySet you'd like. For example, to delete all blog posts with some Post model

Post.objects.all().delete()

and to delete any Post with a future publication date

Post.objects.filter(pub_date__gt=datetime.now()).delete()

You do, however, need to come up with a way to narrow down your QuerySet. If you just want a view to delete a particular object, look into the delete generic view.

EDIT:

Sorry for the misunderstanding. I think the answer is somewhere between. To implement your own, combine ModelForms and generic views. Otherwise, look into 3rd party apps that provide similar functionality. In a related question, the recommendation was django-filter.

How to disable copy/paste from/to EditText

If you are using API level 11 or above then you can stop copy,paste,cut and custom context menus from appearing by.

edittext.setCustomSelectionActionModeCallback(new ActionMode.Callback() {

            public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
                return false;
            }

            public void onDestroyActionMode(ActionMode mode) {                  
            }

            public boolean onCreateActionMode(ActionMode mode, Menu menu) {
                return false;
            }

            public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
                return false;
            }
        });

Returning false from onCreateActionMode(ActionMode, Menu) will prevent the action mode from being started(Select All, Cut, Copy and Paste actions).

ImportError: No module named apiclient.discovery

This can also happen if the interpreter on your IDE is pointing to the wrong virtual environment. In VSCODE I've set it manually to the correct interpreter and my problem was solved.

Adding a Scrollable JTextArea (Java)

  1. Open design view
  2. Right click to textArea
  3. open surround with option
  4. select "...JScrollPane".

HTML5 video won't play in Chrome only

Try this

<video autoplay loop id="video-background" muted plays-inline>
            <source src="https://player.vimeo.com/external/158148793.hd.mp4?s=8e8741dbee251d5c35a759718d4b0976fbf38b6f&profile_id=119&oauth2_token_id=57447761" type="video/mp4">
            </video>

Thanks

How can I convert JSON to CSV?

I was having trouble with Dan's proposed solution, but this worked for me:

import json
import csv 

f = open('test.json')
data = json.load(f)
f.close()

f=csv.writer(open('test.csv','wb+'))

for item in data:
  f.writerow([item['pk'], item['model']] + item['fields'].values())

Where "test.json" contained the following:

[ 
{"pk": 22, "model": "auth.permission", "fields": 
  {"codename": "add_logentry", "name": "Can add log entry", "content_type": 8 } }, 
{"pk": 23, "model": "auth.permission", "fields": 
  {"codename": "change_logentry", "name": "Can change log entry", "content_type": 8 } }, {"pk": 24, "model": "auth.permission", "fields": 
  {"codename": "delete_logentry", "name": "Can delete log entry", "content_type": 8 } }
]

How to clear APC cache entries?

The stable of APC is having option to clear a cache in its interface itself. To clear those entries you must login to apc interface.

APC is having option to set username and password in apc.php file.

enter image description here

Disable elastic scrolling in Safari

None of the 'overflow' solutions worked for me. I'm coding a parallax effect with JavaScript using jQuery. In Chrome and Safari on OSX the elastic/rubber-band effect was messing up my scroll numbers, since it actually scrolls past the document's height and updates the window variables with out-of-boundary numbers. What I had to do was check if the scrolled amount was larger than the actual document's height, like so:

$(window).scroll(
    function() {
        if ($(window).scrollTop() + $(window).height() > $(document).height()) return;
        updateScroll(); // my own function to do my parallaxing stuff
    }
);

What's the difference between a null pointer and a void pointer?

A null pointer is guaranteed to not compare equal to a pointer to any object. It's actual value is system dependent and may vary depending on the type. To get a null int pointer you would do

int* p = 0;

A null pointer will be returned by malloc on failure.

We can test if a pointer is null, i.e. if malloc or some other function failed simply by testing its boolean value:

if (p) {
    /* Pointer is not null */
} else {
    /* Pointer is null */
}

A void pointer can point to any type and it is up to you to handle how much memory the referenced objects consume for the purpose of dereferencing and pointer arithmetic.

How to create a simple checkbox in iOS?

Yeah, no checkbox for you in iOS (-:

Here, this is what I did to create a checkbox:

UIButton *checkbox;
BOOL checkBoxSelected;
checkbox = [[UIButton alloc] initWithFrame:CGRectMake(x,y,20,20)];
// 20x20 is the size of the checkbox that you want
// create 2 images sizes 20x20 , one empty square and
// another of the same square with the checkmark in it
// Create 2 UIImages with these new images, then:

[checkbox setBackgroundImage:[UIImage imageNamed:@"notselectedcheckbox.png"]
                    forState:UIControlStateNormal];
[checkbox setBackgroundImage:[UIImage imageNamed:@"selectedcheckbox.png"]
                    forState:UIControlStateSelected];
[checkbox setBackgroundImage:[UIImage imageNamed:@"selectedcheckbox.png"]
                    forState:UIControlStateHighlighted];
checkbox.adjustsImageWhenHighlighted=YES;
[checkbox addTarget:(nullable id) action:(nonnull SEL) forControlEvents:(UIControlEvents)];
[self.view addSubview:checkbox];

Now in the target method do the following:

-(void)checkboxSelected:(id)sender
{
    checkBoxSelected = !checkBoxSelected; /* Toggle */
    [checkbox setSelected:checkBoxSelected];
}

That's it!

How to return dictionary keys as a list in Python?

If you need to store the keys separately, here's a solution that requires less typing than every other solution presented thus far, using Extended Iterable Unpacking (python3.x+).

newdict = {1: 0, 2: 0, 3: 0}
*k, = newdict

k
# [1, 2, 3]

            +---------------------------------------------------------+
            ¦ k = list(d)   ¦   9 characters (excluding whitespace)   ¦
            +---------------+-----------------------------------------¦
            ¦ k = [*d]      ¦   6 characters                          ¦
            +---------------+-----------------------------------------¦
            ¦ *k, = d       ¦   5 characters                          ¦
            +---------------------------------------------------------+

How to get the first non-null value in Java?

This situation calls for some preprocessor. Because if you write a function (static method) which picks the first not null value, it evaluates all items. It is problem if some items are method calls (may be time expensive method calls). And this methods are called even if any item before them is not null.

Some function like this

public static <T> T coalesce(T ...items) …

should be used but before compiling into byte code there should be a preprocessor which find usages of this „coalesce function“ and replaces it with construction like

a != null ? a : (b != null ? b : c)

Update 2014-09-02:

Thanks to Java 8 and Lambdas there is possibility to have true coalesce in Java! Including the crucial feature: particular expressions are evaluated only when needed – if earlier one is not null, then following ones are not evaluated (methods are not called, computation or disk/network operations are not done).

I wrote an article about it Java 8: coalesce – hledáme neNULLové hodnoty – (written in Czech, but I hope that code examples are understandable for everyone).

Playing a MP3 file in a WinForm application

  1. first go to the properties of your project
  2. click on add references
  3. add the library under COM object for window media player then type your code where you want


    Source:

        WMPLib.WindowsMediaPlayer wplayer = new WMPLib.WindowsMediaPlayer();
    
        wplayer.URL = @"C:\Users\Adil M\Documents\Visual Studio 2012\adil.mp3";
        wplayer.controls.play();