Programs & Examples On #Data paging

Reading Excel files from C#

We use ClosedXML in rather large systems.

  • Free
  • Easy to install
  • Straight forward coding
  • Very responsive support
  • Developer team is extremly open to new suggestions. Often new features and bug fixes are implemented within the same week

node.js require() cache - possible to invalidate?

There's a Simple Module for that (with tests)

We had this exact issue while testing our code (delete cached modules so they can be re-required in a fresh state) so we reviewed all the suggestions of people on the various StackOverflow Questions & Answers and put together a simple node.js module (with tests):

https://www.npmjs.com/package/decache

As you would expect, works for both published npm packages and locally defined modules. Windows, Mac, Linux, etc.

Build Status codecov.io Code Climate maintainability Dependencies Status devDependencies Status

How? (usage)

Usage is pretty simple:

install

Install the module from npm:

npm install decache --save-dev

Use it in your code:

// require the decache module:
const decache = require('decache');

// require a module that you wrote"
let mymod = require('./mymodule.js');

// use your module the way you need to:
console.log(mymod.count()); // 0   (the initial state for our counter is zero)
console.log(mymod.incrementRunCount()); // 1

// delete the cached module:
decache('./mymodule.js');

//
mymod = require('./mymodule.js'); // fresh start
console.log(mymod.count()); // 0   (back to initial state ... zero)

If you have any questions or need more examples, please create a GitHub issue: https://github.com/dwyl/decache/issues

How to create helper file full of functions in react native?

Quick note: You are importing a class, you can't call properties on a class unless they are static properties. Read more about classes here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes

There's an easy way to do this, though. If you are making helper functions, you should instead make a file that exports functions like this:

export function HelloChandu() {

}

export function HelloTester() {

}

Then import them like so:

import { HelloChandu } from './helpers'

or...

import functions from './helpers' then functions.HelloChandu

Adding form action in html in laravel

You need to set a name to your Routes. Like this:


    Route::get('/','WelcomeController@home')->name('welcome.home');
    Route::post('/', array('as' => 'log_in', 'uses' => 'WelcomeController@log_in'))->name('welcome.log_in');
    Route::get('home', 'HomeController@index')->name('home.index');

I just put name on Routes that need this. In my case, to call from tag form at blade template. Like this:

<form action="{{ route('home.index') }}" >

Or, You can do this:

<form action="/" >

SQL to LINQ Tool

I know that this isn't what you asked for but LINQPad is a really great tool to teach yourself LINQ (and it's free :o).

When time isn't critical, I have been using it for the last week or so instead or a query window in SQL Server and my LINQ skills are getting better and better.

It's also a nice little code snippet tool. Its only downside is that the free version doesn't have IntelliSense.

Is <img> element block level or inline level?

<img> is a replaced element; it has a display value of inline by default, but its default dimensions are defined by the embedded image's intrinsic values, like it were inline-block. You can set properties like border/border-radius, padding/margin, width, height, etc. on an image.

Replaced elements : They're elements whose contents are not affected by the current document's styles. The position of the replaced element can be affected using CSS, but not the contents of the replaced element itself.

Referenece : https://developer.mozilla.org/en-US/docs/Web/HTML/Element/img

How to use pip with Python 3.x alongside Python 2.x

If you don't want to have to specify the version every time you use pip:

Install pip:

$ curl https://raw.github.com/pypa/pip/master/contrib/get-pip.py | python3

and export the path:

$ export PATH=/Library/Frameworks/Python.framework/Versions/<version number>/bin:$PATH

Get Wordpress Category from Single Post

How about get_the_category?

You can then do

$category = get_the_category();
$firstCategory = $category[0]->cat_name;

How can I define fieldset border color?

If you don't want 3D border use:

border:#f00 1px solid;

How do I select the "last child" with a specific class name in CSS?

You can use the adjacent sibling selector to achieve something similar, that might help.

.list-item.other-class + .list-item:not(.other-class)

Will effectively target the immediately following element after the last element with the class other-class.

Read more here: https://css-tricks.com/almanac/selectors/a/adjacent-sibling/

Unable to launch the IIS Express Web server, Failed to register URL, Access is denied

What worked for me is disabling all other network adapters, except the one I'm currently using. The event in event viewer was: Unable to bind to the underlying transport for [::]:50064. The IP Listen-Only list may contain a reference to an interface which may not exist on this machine. The data field contains the error number.

Since I have VMware Workstation, Docker (and thus Hyper V) some VPN clients, I have a lot of network interfaces.

Best practice to look up Java Enum

If you want the lookup to be case insensitive you can loop through the values making it a little more friendly:

 public enum MyEnum {
   A, B, C, D;

      public static MyEnum lookup(String id) {
        boolean found = false;
        for(MyEnum enum: values()){
           if(enum.toString().equalsIgnoreCase(id)) found = true;
        }  
        if(!found) throw new RuntimeException("Invalid value for my enum: " +id);
       }
}

Array of PHP Objects

The best place to find answers to general (and somewhat easy questions) such as this is to read up on PHP docs. Specifically in your case you can read more on objects. You can store stdObject and instantiated objects within an array. In fact, there is a process known as 'hydration' which populates the member variables of an object with values from a database row, then the object is stored in an array (possibly with other objects) and returned to the calling code for access.

-- Edit --

class Car
{
    public $color;
    public $type;
}

$myCar = new Car();
$myCar->color = 'red';
$myCar->type = 'sedan';

$yourCar = new Car();
$yourCar->color = 'blue';
$yourCar->type = 'suv';

$cars = array($myCar, $yourCar);

foreach ($cars as $car) {
    echo 'This car is a ' . $car->color . ' ' . $car->type . "\n";
}

get original element from ng-click

Not a direct answer to this question but rather to the "issue" of $event.currentTarget apparently be set to null.

This is due to the fact that console.log shows deep mutable objects at the last state of execution, not at the state when console.log was called.

You can check this for more information: Consecutive calls to console.log produce inconsistent results

Tomcat is not deploying my web project from Eclipse

I have this similar problem where I'm able to start the tomcat server but however application not initialized or started, so I have Right clicked on my project --> Deployment Assembly --> Click 'Add' in the right side panel, select 'Java Build path entries' and click 'Next', Now select 'Maven dependencies' and click 'Finish'. Now I run the server and it started the application successfully.

enter image description here enter image description here
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Difference between iCalendar (.ics) and the vCalendar (.vcs)

The newer iCalendar format, with more data attached, includes information about the person who created the event, so that when it is imported into Outlook (for example), changes to that event are communicated via email to the creator. This can be helpful when you need to inform others of any changes.

However, when I am just exporting an event from one of my calendars to another, I prefer to use vCalendar, since this does not require sending an email message to the creator (usually myself) if I make a change or delete something.

TypeError: 'undefined' is not an object

I'm not sure how you could just check if something isn't undefined and at the same time get an error that it is undefined. What browser are you using?

You could check in the following way (extra = and making length a truthy evaluation)

if (typeof(sub.from) !== 'undefined' && sub.from.length) {

[update]

I see that you reset sub and thereby reset sub.from but fail to re check if sub.from exist:

for (var i = 0; i < sub.from.length; i++) {//<== assuming sub.from.exist
            mainid = sub.from[i]['id'];
            var sub = afcHelper_Submissions[mainid]; // <== re setting sub

My guess is that the error is not on the if statement but on the for(i... statement. In Firebug you can break automatically on an error and I guess it'll break on that line (not on the if statement).

String Pattern Matching In Java

You can use the Pattern class for this. If you want to match only word characters inside the {} then you can use the following regex. \w is a shorthand for [a-zA-Z0-9_]. If you are ok with _ then use \w or else use [a-zA-Z0-9].

String URL = "https://localhost:8080/sbs/01.00/sip/dreamworks/v/01.00/cui/print/$fwVer/{$fwVer}/$lang/en/$model/{$model}/$region/us/$imageBg/{$imageBg}/$imageH/{$imageH}/$imageSz/{$imageSz}/$imageW/{$imageW}/movie/Kung_Fu_Panda_two/categories/3D_Pix/item/{item}/_back/2?$uniqueID={$uniqueID}";
Pattern pattern = Pattern.compile("/\\{\\w+\\}/");
Matcher matcher = pattern.matcher(URL);
if (matcher.find()) {
    System.out.println(matcher.group(0)); //prints /{item}/
} else {
    System.out.println("Match not found");
}

Adding minutes to date time in PHP

PHP's DateTime class has a useful modify method which takes in easy-to-understand text.

$dateTime = new DateTime('2011-11-17 05:05');
$dateTime->modify('+5 minutes');

You could also use string interpolation or concatenation to parameterize it:

$dateTime = new DateTime('2011-11-17 05:05');
$minutesToAdd = 5;
$dateTime->modify("+{$minutesToAdd} minutes");

Create empty file using python

Of course there IS a way to create files without opening. It's as easy as calling os.mknod("newfile.txt"). The only drawback is that this call requires root privileges on OSX.

How to get a time zone from a location using latitude and longitude coordinates?

For those of us using Javascript and looking to get a timezone from a zip code via Google APIs, here is one method.

  1. Fetch the lat/lng via geolocation
  2. fetch the timezone by pass that into the timezone API.
    • Using Luxon here for timezone conversion.

Note: my understanding is that zipcodes are not unique across countries, so this is likely best suited for use in the USA.

const googleMapsClient; // instantiate your client here
const zipcode = '90210'
const myDateThatNeedsTZAdjustment; // define your date that needs adjusting
// fetch lat/lng from google api by zipcode
const geocodeResponse = await googleMapsClient.geocode({ address: zipcode }).asPromise();
if (geocodeResponse.json.status === 'OK') {
  lat = geocodeResponse.json.results[0].geometry.location.lat;
  lng = geocodeResponse.json.results[0].geometry.location.lng;
} else {
  console.log('Geocode was not successful for the following reason: ' + status);
}

// prepare lat/lng and timestamp of profile created_at to fetch time zone
const location = `${lat},${lng}`;
const timestamp = new Date().valueOf() / 1000;
const timezoneResponse = await googleMapsClient
  .timezone({ location: location, timestamp: timestamp })
  .asPromise();

const timeZoneId = timezoneResponse.json.timeZoneId;
// adjust by setting timezone
const timezoneAdjustedDate = DateTime.fromJSDate(
  myDateThatNeedsTZAdjustment
).setZone(timeZoneId);

plot data from CSV file with matplotlib

I'm guessing

x= data[:,0]
y= data[:,1]

How to get the selected row values of DevExpress XtraGrid?

I found the solution as follows:

private void gridView1_RowCellClick(object sender, DevExpress.XtraGrid.Views.Grid.RowCellClickEventArgs e)
{
    TBGRNo.Text = gridView1.GetRowCellValue(gridView1.FocusedRowHandle, "GRNo").ToString();
    TBSName.Text = gridView1.GetRowCellValue(gridView1.FocusedRowHandle, "SName").ToString();
    TBFName.Text = gridView1.GetRowCellValue(gridView1.FocusedRowHandle, "FName").ToString();            
}

enter image description here

Basic communication between two fragments

The nicest and recommended way is to use a shared ViewModel.

https://developer.android.com/topic/libraries/architecture/viewmodel#sharing

From Google doc:

public class SharedViewModel extends ViewModel {
private final MutableLiveData<Item> selected = new MutableLiveData<Item>();

public void select(Item item) {
    selected.setValue(item);
}

public LiveData<Item> getSelected() {
    return selected;
}
}


public class MasterFragment extends Fragment {
private SharedViewModel model;
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    model = ViewModelProviders.of(getActivity()).get(SharedViewModel.class);
    itemSelector.setOnClickListener(item -> {
        model.select(item);
    });
}
}


public class DetailFragment extends Fragment {
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    SharedViewModel model = ViewModelProviders.of(getActivity()).get(SharedViewModel.class);
    model.getSelected().observe(this, { item ->
       // Update the UI.
    });
}
}

ps: two fragments never communicate directly

Create a File object in memory from a string in Java

The File class represents the "idea" of a file, not an actual handle to use for I/O. This is why the File class has a .exists() method, to tell you if the file exists or not. (How can you have a File object that doesn't exist?)

By contrast, constructing a new FileInputStream(new File("/my/file")) gives you an actual stream to read bytes from.

Firebase onMessageReceived not called when app in background

Override the handleIntent Method of the FirebaseMessageService works for me.

here the code in C# (Xamarin)

public override void HandleIntent(Intent intent)
{
    try
    {
        if (intent.Extras != null)
        {
            var builder = new RemoteMessage.Builder("MyFirebaseMessagingService");

            foreach (string key in intent.Extras.KeySet())
            {
                builder.AddData(key, intent.Extras.Get(key).ToString());
            }

            this.OnMessageReceived(builder.Build());
        }
        else
        {
            base.HandleIntent(intent);
        }
    }
    catch (Exception)
    {
        base.HandleIntent(intent);
    }
}

and thats the Code in Java

public void handleIntent(Intent intent)
{
    try
    {
        if (intent.getExtras() != null)
        {
            RemoteMessage.Builder builder = new RemoteMessage.Builder("MyFirebaseMessagingService");

            for (String key : intent.getExtras().keySet())
            {
                builder.addData(key, intent.getExtras().get(key).toString());
            }

            onMessageReceived(builder.build());
        }
        else
        {
            super.handleIntent(intent);
        }
    }
    catch (Exception e)
    {
        super.handleIntent(intent);
    }
}

Installing Python packages from local file system folder to virtualenv with pip

I am installing pyfuzzybut is is not in PyPI; it returns the message: No matching distribution found for pyfuzzy.

I tried the accepted answer

pip install  --no-index --find-links=file:///Users/victor/Downloads/pyfuzzy-0.1.0 pyfuzzy

But it does not work either and returns the following error:

Ignoring indexes: https://pypi.python.org/simple Collecting pyfuzzy Could not find a version that satisfies the requirement pyfuzzy (from versions: ) No matching distribution found for pyfuzzy

At last , I have found a simple good way there: https://pip.pypa.io/en/latest/reference/pip_install.html

Install a particular source archive file.
$ pip install ./downloads/SomePackage-1.0.4.tar.gz
$ pip install http://my.package.repo/SomePackage-1.0.4.zip

So the following command worked for me:

pip install ../pyfuzzy-0.1.0.tar.gz.

Hope it can help you.

Why does Date.parse give incorrect results?

Another solution is to build an associative array with date format and then reformat data.

This method is useful for date formatted in an unussual way.

An example:

    mydate='01.02.12 10:20:43':
    myformat='dd/mm/yy HH:MM:ss';


    dtsplit=mydate.split(/[\/ .:]/);
    dfsplit=myformat.split(/[\/ .:]/);

    // creates assoc array for date
    df = new Array();
    for(dc=0;dc<6;dc++) {
            df[dfsplit[dc]]=dtsplit[dc];
            }

    // uses assc array for standard mysql format
    dstring[r] = '20'+df['yy']+'-'+df['mm']+'-'+df['dd'];
    dstring[r] += ' '+df['HH']+':'+df['MM']+':'+df['ss'];

Modify a Column's Type in sqlite3

It is possible by recreating table.Its work for me please follow following step:

  1. create temporary table using as select * from your table
  2. drop your table, create your table using modify column type
  3. now insert records from temp table to your newly created table
  4. drop temporary table

do all above steps in worker thread to reduce load on uithread

Scroll to a div using jquery

No need too these. Just simply add div id to href of a < a > tag

<li><a id = "aboutlink" href="#about">auck</a></li>

Just like that.

Undefined reference to 'vtable for xxx'

If a class defines virtual methods outside that class, then g++ generates the vtable only in the object file that contains the outside-of-class definition of the virtual method that was declared first:

//test.h
struct str
{
   virtual void f();
   virtual void g();
};

//test1.cpp
#include "test.h"
void str::f(){}

//test2.cpp
#include "test.h"
void str::g(){}

The vtable will be in test1.o, but not in test2.o

This is an optimisation g++ implements to avoid having to compile in-class-defined virtual methods that would get pulled in by the vtable.

The link error you describe suggests that the definition of a virtual method (str::f in the example above) is missing in your project.

When to use AtomicReference in Java?

Here's a very simple use case and has nothing to do with thread safety.

To share an object between lambda invocations, the AtomicReference is an option:

public void doSomethingUsingLambdas() {

    AtomicReference<YourObject> yourObjectRef = new AtomicReference<>();

    soSomethingThatTakesALambda(() -> {
        yourObjectRef.set(youObject);
    });

    soSomethingElseThatTakesALambda(() -> {
        YourObject yourObject = yourObjectRef.get();
    });
}

I'm not saying this is good design or anything (it's just a trivial example), but if you have have the case where you need to share an object between lambda invocations, the AtomicReference is an option.

In fact you can use any object that holds a reference, even a Collection that has only one item. However, the AtomicReference is a perfect fit.

Undo a Git merge that hasn't been pushed yet

If you want a command-line solution, I suggest to just go with MBO's answer.

If you're a newbie, you might like the graphical approach:

  1. Kick off gitk (from the command line, or right click in file browser if you have that)
  2. You can easily spot the merge commit there - the first node from the top with two parents
  3. Follow the link to the first/left parent (the one on your current branch before the merge, usually red for me)
  4. On the selected commit, right-click "Reset branch to here", pick the hard reset there

XXHDPI and XXXHDPI dimensions in dp for images and icons in android

try like this. hope it works

drawable-sw720dp-xxhdpi and values-sw720dp-xxhdpi

drawable-sw720dp-xxxhdpi and values-sw720dp-xxxhdpi

link might destroy so pasted ans

reference Android xxx-hdpi real devices

xxxhdpi was only introduced because of the way that launcher icons are scaled on the nexus 5's launcher Because the nexus 5's default launcher uses bigger icons, xxxhdpi was introduced so that icons would still look good on the nexus 5's launcher.

also check these links

Different resolution support android

Application Skeleton to support multiple screen

Is there a list of screen resolutions for all Android based phones and tablets?

Unzip a file with php

you can use prepacked function

function unzip_file($file, $destination){
    // create object
    $zip = new ZipArchive() ;
    // open archive
    if ($zip->open($file) !== TRUE) {
        return false;
    }
    // extract contents to destination directory
    $zip->extractTo($destination);
    // close archive
    $zip->close();
        return true;
}

How to use it.

if(unzip_file($file["name"],'uploads/')){
echo 'zip archive extracted successfully';
}else{
  echo 'zip archive extraction failed';
}

Ansible - Use default if a variable is not defined

If you have a single play that you want to loop over the items, define that list in group_vars/all or somewhere else that makes sense:

all_items:
  - first
  - second
  - third
  - fourth

Then your task can look like this:

  - name: List items or default list
    debug:
      var: item
    with_items: "{{ varlist | default(all_items) }}"

Pass in varlist as a JSON array:

ansible-playbook <playbook_name> --extra-vars='{"varlist": [first,third]}'

Prior to that, you might also want a task that checks that each item in varlist is also in all_items:

  - name: Ensure passed variables are in all_items
    fail:
      msg: "{{ item }} not  in all_items list"
    when: item not in all_items
    with_items: "{{ varlist | default(all_items) }}"

Warning: Cannot modify header information - headers already sent by ERROR

Those blank lines between your ?> and <?php tags are being sent to the client.

When the first one of those is sent, it causes your headers to be sent first.

Once that happens, you can't modify the headers any more.

Remove those unnecessary tags, have it all in one big <?php block.

How to make a PHP SOAP call using the SoapClient class

getLastRequest():

This method works only if the SoapClient object was created with the trace option set to TRUE.

TRUE in this case is represented by 1

$wsdl = storage_path('app/mywsdl.wsdl');
try{

  $options = array(
               // 'soap_version'=>SOAP_1_1,
               'trace'=>1,
               'exceptions'=>1,

                'cache_wsdl'=>WSDL_CACHE_NONE,
             //   'stream_context' => stream_context_create($arrContextOptions)
        );
           // $client = new \SoapClient($wsdl, array('cache_wsdl' => WSDL_CACHE_NONE) );
        $client = new \SoapClient($wsdl, array('cache_wsdl' => WSDL_CACHE_NONE));
        $client     = new \SoapClient($wsdl,$options); 

worked for me.

Windows 7 - Add Path

Another method that worked for me on Windows 7 that did not require administrative privileges:

Click on the Start menu, search for "environment," click "Edit environment variables for your account."

In the window that opens, select "PATH" under "User variables for username" and click the "Edit..." button. Add your new path to the end of the existing Path, separated by a semi-colon (%PATH%;C:\Python27;...;C:\NewPath). Click OK on all the windows, open a new CMD window, and test the new variable.

How to hide element using Twitter Bootstrap and show it using jQuery?

$(function(){

$("#my-div").toggle();

$("#my-div").click(function(){$("#my-div").toggle()})

})

// you don't even have to set the #my-div .hide nor !important, just paste/repeat the toggle in the event function.

Android 'Unable to add window -- token null is not for an application' exception

I got the same exception. what i do to fix this is to pass instance of the dialog as parameter into function and use it instead of pass only context then using getContext(). this solution solve my problem, hope it can help

Html.EditorFor Set Default Value

Its not right to set default value in View. The View should perform display work, not more. This action breaks ideology of MVC pattern. So the right place to set defaults - create method of controller class.

Multi-Line Comments in Ruby?

#!/usr/bin/env ruby

=begin
Between =begin and =end, any number
of lines may be written. All of these
lines are ignored by the Ruby interpreter.
=end

puts "Hello world!"

How can I remove duplicate rows?

DELETE 
FROM MyTable
WHERE NOT EXISTS (
              SELECT min(RowID)
              FROM Mytable
              WHERE (SELECT RowID 
                     FROM Mytable
                     GROUP BY Col1, Col2, Col3
                     ))
               );

PHP header() redirect with POST variables

It would be beneficial to verify the form's data before sending it via POST. You should create a JavaScript function to check the form for errors and then send the form. This would prevent the data from being sent over and over again, possibly slowing the browser and using transfer volume on the server.

Edit:

If security is a concern, performing an AJAX request to verify the data would be the best way. The response from the AJAX request would determine whether the form should be submitted.

How to allow only one radio button to be checked?

All radio buttons have to have the same name:

<input type='radio' name='foo'>

Only 1 radio button of each group of buttons with the same name can be checked.

Using Mockito to stub and execute methods for testing

So, the idea of mocking the class under test is anathima to testing practice. You should NOT do this. Because you have done so, your test is entering Mockito's mocking classes not your class under test.

Spying will also not work because this only provides a wrapper / proxy around the spied class. Once execution is inside the class it will not go through the proxy and therefore not hit the spy. UPDATE: although I believe this to be true of Spring proxies it appears to not be true of Mockito spies. I set up a scenario where method m1() calls m2(). I spy the object and stub m2() to doNothing. When I invoke m1() in my test, m2() of the class is not reached. Mockito invokes the stub. So using a spy to accomplish what is being asked is possible. However, I would reiterate that I would consider it bad practice (IMHO).

You should mock all the classes on which the class under test depends. This will allow you to control the behavior of the methods invoked by the method under test in that you control the class that those methods invoke.

If your class creates instances of other classes, consider using factories.

What is 'PermSize' in Java?

A quick definition of the "permanent generation":

"The permanent generation is used to hold reflective data of the VM itself such as class objects and method objects. These reflective objects are allocated directly into the permanent generation, and it is sized independently from the other generations." [ref]

In other words, this is where class definitions go (and this explains why you may get the message OutOfMemoryError: PermGen space if an application loads a large number of classes and/or on redeployment).

Note that PermSize is additional to the -Xmx value set by the user on the JVM options. But MaxPermSize allows for the JVM to be able to grow the PermSize to the amount specified. Initially when the VM is loaded, the MaxPermSize will still be the default value (32mb for -client and 64mb for -server) but will not actually take up that amount until it is needed. On the other hand, if you were to set BOTH PermSize and MaxPermSize to 256mb, you would notice that the overall heap has increased by 256mb additional to the -Xmx setting.

Calling other function in the same controller?

Yes. Problem is in wrong notation. Use:

$this->sendRequest($uri)

Instead. Or

self::staticMethod()

for static methods. Also read this for getting idea of OOP - http://www.php.net/manual/en/language.oop5.basic.php

How do I insert a JPEG image into a python Tkinter window?

from tkinter import *
from PIL import ImageTk, Image

window = Tk()
window.geometry("1000x300")

path = "1.jpg"

image = PhotoImage(Image.open(path))

panel = Label(window, image = image)

panel.pack()

window.mainloop()

Spring MVC - Why not able to use @RequestBody and @RequestParam together

The @RequestBody javadoc states

Annotation indicating a method parameter should be bound to the body of the web request.

It uses registered instances of HttpMessageConverter to deserialize the request body into an object of the annotated parameter type.

And the @RequestParam javadoc states

Annotation which indicates that a method parameter should be bound to a web request parameter.

  1. Spring binds the body of the request to the parameter annotated with @RequestBody.

  2. Spring binds request parameters from the request body (url-encoded parameters) to your method parameter. Spring will use the name of the parameter, ie. name, to map the parameter.

  3. Parameters are resolved in order. The @RequestBody is processed first. Spring will consume all the HttpServletRequest InputStream. When it then tries to resolve the @RequestParam, which is by default required, there is no request parameter in the query string or what remains of the request body, ie. nothing. So it fails with 400 because the request can't be correctly handled by the handler method.

  4. The handler for @RequestParam acts first, reading what it can of the HttpServletRequest InputStream to map the request parameter, ie. the whole query string/url-encoded parameters. It does so and gets the value abc mapped to the parameter name. When the handler for @RequestBody runs, there's nothing left in the request body, so the argument used is the empty string.

  5. The handler for @RequestBody reads the body and binds it to the parameter. The handler for @RequestParam can then get the request parameter from the URL query string.

  6. The handler for @RequestParam reads from both the body and the URL query String. It would usually put them in a Map, but since the parameter is of type String, Spring will serialize the Map as comma separated values. The handler for @RequestBody then, again, has nothing left to read from the body.

Remove duplicated rows

just isolate your data frame to the columns you need, then use the unique function :D

# in the above example, you only need the first three columns
deduped.data <- unique( yourdata[ , 1:3 ] )
# the fourth column no longer 'distinguishes' them, 
# so they're duplicates and thrown out.

Detecting locked tables (locked by LOCK TABLE)

The following answer was written by Eric Leschinki in 2014/15 at https://stackoverflow.com/a/26743484/1709587 (now deleted):

Mini walkthrough on how to detect locked tables:

This may prevent the database from enforcing atomicity in the affected tables and rows. The locks were designed to make sure things stay consistent and this procedure will prevent that process from taking place as designed.

Create your table, insert some rows

create table penguins(spam int, ham int);
insert into penguins(spam, ham) values (3, 4);

show open tables:

show open tables like "penguins"

prints:

your_database penguins    0   0

Penguins isn't locked, lets lock it:

LOCK TABLES penguins READ;

Check if it's locked:

show open tables like "penguins"

Prints:

your_database, penguins 1, 0

Aha! It is locked! Lets unlock it:

unlock tables

Now it is unlocked:

show open tables like "penguins"

Prints:

your_database penguins    0   0

show all current locks

show open tables where in_use <> 0

It would be much more helpful if the MySQL developers put this information in a regular table (so I can do a select my_items from my_table where my_clauses), rather than this stripped down 'show table' syntax from system variables.

Why is the minidlna database not being refreshed?

Resolved with crontab root

10 * * * * /usr/bin/minidlnad -r

Cannot insert explicit value for identity column in table 'table' when IDENTITY_INSERT is set to OFF

In my CASE I was inserting more character than defined in table.

In My Table column was defined with nvarchar(3) and I was passing more than 3 characters and same ERROR message was coming .

Its not answer but may be in some case problem is similar

Git Push Error: insufficient permission for adding an object to repository database

Linux, macOS:

cd .git/
sudo chown -R name:group *

where name is your username and group is the group that your username belongs to.

Android Service Stops When App Is Closed

make you service like this in your Mainifest

 <service
            android:name=".sys.service.youservice"
            android:exported="true"
        android:process=":ServiceProcess" />

then your service will run on other process named ServiceProcess


if you want make your service never die :

  1. onStartCommand() return START_STICKY

  2. onDestroy() -> startself

  3. create a Deamon service

  4. jin -> create a Native Deamon process, you can find some open-source projects on github

  5. startForeground() , there is a way to startForeground without Notification ,google it

Handling null values in Freemarker

Starting from freemarker 2.3.7, you can use this syntax :

${(object.attribute)!}

or, if you want display a default text when the attribute is null :

${(object.attribute)!"default text"}

Wildcards in a Windows hosts file

I found a posting about Using the Windows Hosts File that also says "No wildcards are allowed."

In the past, I have just added the additional entries to the hosts file, because (as previously said), it's not that much extra work when you already are editing the apache config file.

Generating Unique Random Numbers in Java

I have easy solution for this problem, With this we can easily generate n number of unique random numbers, Its just logic anyone can use it in any language.

for(int i=0;i<4;i++)
        {
            rn[i]= GenerateRandomNumber();
            for (int j=0;j<i;j++)
            {
                if (rn[i] == rn[j])
                {
                    i--;
                }
            }
        }

Initializing a static std::map<int, int> in C++

If you are stuck with C++98 and don't want to use boost, here there is the solution I use when I need to initialize a static map:

typedef std::pair< int, char > elemPair_t;
elemPair_t elemPairs[] = 
{
    elemPair_t( 1, 'a'), 
    elemPair_t( 3, 'b' ), 
    elemPair_t( 5, 'c' ), 
    elemPair_t( 7, 'd' )
};

const std::map< int, char > myMap( &elemPairs[ 0 ], &elemPairs[ sizeof( elemPairs ) / sizeof( elemPairs[ 0 ] ) ] );

Recommended way of making React component/div draggable

Here's a simple modern approach to this with useState, useEffect and useRef in ES6.

import React, { useRef, useState, useEffect } from 'react'

const quickAndDirtyStyle = {
  width: "200px",
  height: "200px",
  background: "#FF9900",
  color: "#FFFFFF",
  display: "flex",
  justifyContent: "center",
  alignItems: "center"
}

const DraggableComponent = () => {
  const [pressed, setPressed] = useState(false)
  const [position, setPosition] = useState({x: 0, y: 0})
  const ref = useRef()

  // Monitor changes to position state and update DOM
  useEffect(() => {
    if (ref.current) {
      ref.current.style.transform = `translate(${position.x}px, ${position.y}px)`
    }
  }, [position])

  // Update the current position if mouse is down
  const onMouseMove = (event) => {
    if (pressed) {
      setPosition({
        x: position.x + event.movementX,
        y: position.y + event.movementY
      })
    }
  }

  return (
    <div
      ref={ ref }
      style={ quickAndDirtyStyle }
      onMouseMove={ onMouseMove }
      onMouseDown={ () => setPressed(true) }
      onMouseUp={ () => setPressed(false) }>
      <p>{ pressed ? "Dragging..." : "Press to drag" }</p>
    </div>
  )
}

export default DraggableComponent

How to Bulk Insert from XLSX file extension?

you can save the xlsx file as a tab-delimited text file and do

BULK INSERT TableName
        FROM 'C:\SomeDirectory\my table.txt'
            WITH
    (
                FIELDTERMINATOR = '\t',
                ROWTERMINATOR = '\n'
    )
GO

Unicode via CSS :before

In CSS, FontAwesome unicode works only when the correct font family is declared (version 4 or less):

font-family: "FontAwesome";
content: "\f066";

Update - Version 5 has different names:

Free

font-family: "Font Awesome 5 Free"

Pro

font-family: "Font Awesome 5 Pro"

Brands

font-family: "Font Awesome 5 Brands"

See this related answer: https://stackoverflow.com/a/48004111/2575724

As per comment (BuddyZ) some more info here https://fontawesome.com/how-to-use/on-the-desktop/setup/getting-started

JavaScript click event listener on class

Yow can use querySelectorAll to select all the classes and loop through them to assign the eventListener. The if condition checks if it contains the class name.

const arrClass = document.querySelectorAll(".className");
for (let i of arrClass) {
  i.addEventListener("click", (e) => {
    if (e.target.classList.contains("className")) {
        console.log("Perfrom Action")
    }
  })
}

Android webview slow

The solution for us was the opposite. We disabled hardware acceleration on the WebView only (rather than on the entire app in the manifest) by using this code:

if (Build.VERSION.SDK_INT >= 11){
    webview.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
}

CSS3 animations are smoother now. We are using Android 4.0.

More info here: https://code.google.com/p/android/issues/detail?id=17352

How to create a connection string in asp.net c#

string connectionstring="DataSource=severname;InitialCatlog=databasename;Uid=; password=;"
SqlConnection con=new SqlConnection(connectionstring)

How can I conditionally import an ES6 module?

You can't import conditionally, but you can do the opposite: export something conditionally. It depends on your use case, so this work around might not be for you.

You can do:

api.js

import mockAPI from './mockAPI'
import realAPI from './realAPI'

const exportedAPI = shouldUseMock ? mockAPI : realAPI
export default exportedAPI

apiConsumer.js

import API from './api'
...

I use that to mock analytics libs like mixpanel, etc... because I can't have multiple builds or our frontend currently. Not the most elegant, but works. I just have a few 'if' here and there depending on the environment because in the case of mixpanel, it needs initialization.

Jackson JSON: get node name from json-tree

For Jackson 2+ (com.fasterxml.jackson), the methods are little bit different:

Iterator<Entry<String, JsonNode>> nodes = rootNode.get("foo").fields();

while (nodes.hasNext()) {
  Map.Entry<String, JsonNode> entry = (Map.Entry<String, JsonNode>) nodes.next();

  logger.info("key --> " + entry.getKey() + " value-->" + entry.getValue());
}

Create a folder if it doesn't already exist

Faster way to create folder:

if (!is_dir('path/to/directory')) {
    mkdir('path/to/directory', 0777, true);
}

Using CMake with GNU Make: How can I see the exact commands?

It is convenient to set the option in the CMakeLists.txt file as:

set(CMAKE_VERBOSE_MAKEFILE ON)

JavaScript: set dropdown selected item based on option text

var textToFind = 'Google';

var dd = document.getElementById('MyDropDown');
for (var i = 0; i < dd.options.length; i++) {
    if (dd.options[i].text === textToFind) {
        dd.selectedIndex = i;
        break;
    }
}

running a command as a super user from a python script

Another way is to make your user a password-less sudo user.

Type the following on command line:

sudo visudo

Then add the following and replace the <username> with yours:

<username> ALL=(ALL) NOPASSWD: ALL

This will allow the user to execute sudo command without having to ask for password (including application launched by the said user. This might be a security risk though

Count character occurrences in a string in C++

Using the lambda function to check the character is "_" then only count will be incremented else not a valid character

std::string s = "a_b_c";
size_t count = std::count_if( s.begin(), s.end(), []( char c ){if(c =='_') return true; });
std::cout << "The count of numbers: " << count << std::endl;

How to prevent rm from reporting that a file was not found?

Yes, -f is the most suitable option for this.

Convert a string to datetime in PowerShell

Hope below helps!

PS C:\Users\aameer>$invoice = $object.'Invoice Month'
$invoice = "01-" + $invoice
[datetime]$Format_date =$invoice

Now type is converted. You can use method or can access any property.

Example :$Format_date.AddDays(5)

Access multiple elements of list knowing their index

Alternatives:

>>> map(a.__getitem__, b)
[1, 5, 5]

>>> import operator
>>> operator.itemgetter(*b)(a)
(1, 5, 5)

Hashing a file in Python

For the correct and efficient computation of the hash value of a file (in Python 3):

  • Open the file in binary mode (i.e. add 'b' to the filemode) to avoid character encoding and line-ending conversion issues.
  • Don't read the complete file into memory, since that is a waste of memory. Instead, sequentially read it block by block and update the hash for each block.
  • Eliminate double buffering, i.e. don't use buffered IO, because we already use an optimal block size.
  • Use readinto() to avoid buffer churning.

Example:

import hashlib

def sha256sum(filename):
    h  = hashlib.sha256()
    b  = bytearray(128*1024)
    mv = memoryview(b)
    with open(filename, 'rb', buffering=0) as f:
        for n in iter(lambda : f.readinto(mv), 0):
            h.update(mv[:n])
    return h.hexdigest()

How to check if a process id (PID) exists

The best way is:

if ps -p $PID > /dev/null
then
   echo "$PID is running"
   # Do something knowing the pid exists, i.e. the process with $PID is running
fi

The problem with:

kill -0 $PID

is the exit code will be non-zero even if the pid is running and you dont have permission to kill it. For example:

kill -0 1

and

kill -0 $non-running-pid

have an indistinguishable (non-zero) exit code for a normal user, but the init process (PID 1) is certainly running.

DISCUSSION

The answers discussing kill and race conditions are exactly right if the body of the test is a "kill". I came looking for the general "how do you test for a PID existence in bash".

The /proc method is interesting, but in some sense breaks the spirit of the "ps" command abstraction, i.e. you dont need to go looking in /proc because what if Linus decides to call the "exe" file something else?

package javax.servlet.http does not exist

If you use elcipse with tomcat server, you can open setting properties by right click project -> choose Properties (or Alt+Enter), continue do same below picture. It will resolve your problem.

enter image description here

Set Canvas size using javascript

Try this:

var setCanvasSize = function() {
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
}

What does O(log n) mean exactly?

But what exactly is O(log n)

What it means precisely is "as n tends towards infinity, the time tends towards a*log(n) where a is a constant scaling factor".

Or actually, it doesn't quite mean that; more likely it means something like "time divided by a*log(n) tends towards 1".

"Tends towards" has the usual mathematical meaning from 'analysis': for example, that "if you pick any arbitrarily small non-zero constant k, then I can find a corresponding value X such that ((time/(a*log(n))) - 1) is less than k for all values of n greater than X."


In lay terms, it means that the equation for time may have some other components: e.g. it may have some constant startup time; but these other components pale towards insignificance for large values of n, and the a*log(n) is the dominating term for large n.

Note that if the equation were, for example ...

time(n) = a + blog(n) + cn + dnn

... then this would be O(n squared) because, no matter what the values of the constants a, b, c, and non-zero d, the d*n*n term would always dominate over the others for any sufficiently large value of n.

That's what bit O notation means: it means "what is the order of dominant term for any sufficiently large n".

How do I configure different environments in Angular.js?

I'm a little late to the thread, but if you're using Grunt I've had great success with grunt-ng-constant.

The config section for ngconstant in my Gruntfile.js looks like

ngconstant: {
  options: {
    name: 'config',
    wrap: '"use strict";\n\n{%= __ngModule %}',
    space: '  '
  },
  development: {
    options: {
      dest: '<%= yeoman.app %>/scripts/config.js'
    },
    constants: {
      ENV: 'development'
    }
  },
  production: {
    options: {
      dest: '<%= yeoman.dist %>/scripts/config.js'
    },
    constants: {
      ENV: 'production'
    }
  }
}

The tasks that use ngconstant look like

grunt.registerTask('server', function (target) {
  if (target === 'dist') {
    return grunt.task.run([
      'build',
      'open',
      'connect:dist:keepalive'
    ]);
  }

  grunt.task.run([
    'clean:server',
    'ngconstant:development',
    'concurrent:server',
    'connect:livereload',
    'open',
    'watch'
  ]);
});

grunt.registerTask('build', [
  'clean:dist',
  'ngconstant:production',
  'useminPrepare',
  'concurrent:dist',
  'concat',
  'copy',
  'cdnify',
  'ngmin',
  'cssmin',
  'uglify',
  'rev',
  'usemin'
]);

So running grunt server will generate a config.js file in app/scripts/ that looks like

"use strict";
angular.module("config", []).constant("ENV", "development");

Finally, I declare the dependency on whatever modules need it:

// the 'config' dependency is generated via grunt
var app = angular.module('myApp', [ 'config' ]);

Now my constants can be dependency injected where needed. E.g.,

app.controller('MyController', ['ENV', function( ENV ) {
  if( ENV === 'production' ) {
    ...
  }
}]);

How to implement Enums in Ruby?

Sometimes all I need is to be able to fetch enum's value and identify its name similar to java world.

module Enum
     def get_value(str)
       const_get(str)
     end
     def get_name(sym)
       sym.to_s.upcase
     end
 end

 class Fruits
   include Enum
   APPLE = "Delicious"
   MANGO = "Sweet"
 end

 Fruits.get_value('APPLE') #'Delicious'
 Fruits.get_value('MANGO') # 'Sweet'

 Fruits.get_name(:apple) # 'APPLE'
 Fruits.get_name(:mango) # 'MANGO'

This to me serves the purpose of enum and keeps it very extensible too. You can add more methods to the Enum class and viola get them for free in all the defined enums. for example. get_all_names and stuff like that.

Can't find System.Windows.Media namespace?

You can add PresentationCore.dll more conveniently by editing the project file. Add the following code into your csproj file:

<ItemGroup>
   <FrameworkReference Include="Microsoft.WindowsDesktop.App" />
</ItemGroup>

In your solution explorer, you now should see this framework listed, now. With that, you then can also refer to the classes provided by PresentationCore.dll.

What's the best way to calculate the size of a directory in .NET?

The fastest way that I came up is using EnumerateFiles with SearchOption.AllDirectories. This method also allows updating the UI while going through the files and counting the size. Long path names don't cause any problems since FileInfo or DirectoryInfo are not tried to be created for the long path name. While enumerating files even though the filename is long the FileInfo returned by the EnumerateFiles don't cause problems as long as the starting directory name is not too long. There is still a problem with UnauthorizedAccess.

    private void DirectoryCountEnumTest(string sourceDirName)
    {
        // Get the subdirectories for the specified directory.
        long dataSize = 0;
        long fileCount = 0;
        string prevText = richTextBox1.Text;

        if (Directory.Exists(sourceDirName))
        {
            DirectoryInfo dir = new DirectoryInfo(sourceDirName);
            foreach (FileInfo file in dir.EnumerateFiles("*", SearchOption.AllDirectories))
            {
                fileCount++;
                try
                {
                    dataSize += file.Length;
                    richTextBox1.Text = prevText + ("\nCounting size: " + dataSize.ToString());
                }
                catch (Exception e)
                {
                    richTextBox1.AppendText("\n" + e.Message);
                }
            }
            richTextBox1.AppendText("\n files:" + fileCount.ToString());
        }
    }

Remove all html tags from php string

For my this is best solution.

function strip_tags_content($string) { 
    // ----- remove HTML TAGs ----- 
    $string = preg_replace ('/<[^>]*>/', ' ', $string); 
    // ----- remove control characters ----- 
    $string = str_replace("\r", '', $string);
    $string = str_replace("\n", ' ', $string);
    $string = str_replace("\t", ' ', $string);
    // ----- remove multiple spaces ----- 
    $string = trim(preg_replace('/ {2,}/', ' ', $string));
    return $string; 

}

Javascript Error Null is not an Object

Any JS code which executes and deals with DOM elements should execute after the DOM elements have been created. JS code is interpreted from top to down as layed out in the HTML. So, if there is a tag before the DOM elements, the JS code within script tag will execute as the browser parses the HTML page.

So, in your case, you can put your DOM interacting code inside a function so that only function is defined but not executed.

Then you can add an event listener for document load to execute the function.

That will give you something like:

<script>
  function init() {
    var myButton = document.getElementById("myButton");
    var myTextfield = document.getElementById("myTextfield");
    myButton.onclick = function() {
      var userName = myTextfield.value;
      greetUser(userName);
    }
  }

  function greetUser(userName) {
    var greeting = "Hello " + userName + "!";
    document.getElementsByTagName ("h2")[0].innerHTML = greeting;
  }

  document.addEventListener('readystatechange', function() {
    if (document.readyState === "complete") {
      init();
    }
  });

</script>
<h2>Hello World!</h2>
<p id="myParagraph">This is an example website</p>

<form>
  <input type="text" id="myTextfield" placeholder="Type your name" />
  <input type="button" id="myButton" value="Go" />
</form>

Fiddle at - http://jsfiddle.net/poonia/qQMEg/4/

Where does PHP's error log reside in XAMPP?

\xampp\apache\logs\error.log is the default location of error logs in php.

detect back button click in browser

best way I know

         window.onbeforeunload = function (e) {
            var e = e || window.event;
            var msg = "Do you really want to leave this page?"

            // For IE and Firefox
            if (e) {
                e.returnValue = msg;
            }

            // For Safari / chrome
            return msg;
         };

Accuracy Score ValueError: Can't Handle mix of binary and continuous target

The error is because difference in datatypes of y_pred and y_true. y_true might be dataframe and y_pred is arraylist. If you convert both to arrays, then issue will get resolved.

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

I was facing similar issue.

  1. You need to remove all the CSP parameter which are picked up by default and understand why each attribute is required.

font-src - is to tell the browser to load the font's from src which is specified after that. font-src: 'self' - this tells to load font family within the same origin or system. font-src: 'self' data: - this tells load font-family within the same origin and the calls made to get data:

You might also get warning "** Failed to decode downloaded font, OTS parsing error: invalid version tag **" Add the following entry in CSP.

font-src: 'self' font

This should now load with no errors.

What is the difference between GitHub and gist?

You can access Gist by visiting the following url gist.github.com. Alternatively you can access it from within your Github account (after logging in) as shown in the picture below:

how to access gist from within the github console

 

Github: A hosting service that houses a web-based git repository. It includes all the fucntionality of git with additional features added in.

 

Gist: Is an additional feature added to github to allow the sharing of code snippets, notes, to do lists and more. You can save your Gists as secret or public. Secret Gists are hidden from search engines but visible to anyone you share the url with.

For example. If you wanted to write a private to-do list. You could write one using Github Markdown as follows:

how to write a private to do list

NB: It is important to preserve the whitespace as shown above between the dash and brackets. It is also important that you save the file with the extension .md because we want the markdown to format properly. Remember to save this Gist as secret if you do not want others to see it.

 

The end result looks like the image below. The checkboxes are clickable because we saved this Gist with the extension .md

What the to do list looks like if you have formatted it properly

How to print like printf in Python3?

print("Name={}, balance={}".format(var-name, var-balance))

Login to website, via C#

You can continue using WebClient to POST (instead of GET, which is the HTTP verb you're currently using with DownloadString), but I think you'll find it easier to work with the (slightly) lower-level classes WebRequest and WebResponse.

There are two parts to this - the first is to post the login form, the second is recovering the "Set-cookie" header and sending that back to the server as "Cookie" along with your GET request. The server will use this cookie to identify you from now on (assuming it's using cookie-based authentication which I'm fairly confident it is as that page returns a Set-cookie header which includes "PHPSESSID").


POSTing to the login form

Form posts are easy to simulate, it's just a case of formatting your post data as follows:

field1=value1&field2=value2

Using WebRequest and code I adapted from Scott Hanselman, here's how you'd POST form data to your login form:

string formUrl = "http://www.mmoinn.com/index.do?PageModule=UsersAction&Action=UsersLogin"; // NOTE: This is the URL the form POSTs to, not the URL of the form (you can find this in the "action" attribute of the HTML's form tag
string formParams = string.Format("email_address={0}&password={1}", "your email", "your password");
string cookieHeader;
WebRequest req = WebRequest.Create(formUrl);
req.ContentType = "application/x-www-form-urlencoded";
req.Method = "POST";
byte[] bytes = Encoding.ASCII.GetBytes(formParams);
req.ContentLength = bytes.Length;
using (Stream os = req.GetRequestStream())
{
    os.Write(bytes, 0, bytes.Length);
}
WebResponse resp = req.GetResponse();
cookieHeader = resp.Headers["Set-cookie"];

Here's an example of what you should see in the Set-cookie header for your login form:

PHPSESSID=c4812cffcf2c45e0357a5a93c137642e; path=/; domain=.mmoinn.com,wowmine_referer=directenter; path=/; domain=.mmoinn.com,lang=en; path=/;domain=.mmoinn.com,adt_usertype=other,adt_host=-

GETting the page behind the login form

Now you can perform your GET request to a page that you need to be logged in for.

string pageSource;
string getUrl = "the url of the page behind the login";
WebRequest getRequest = WebRequest.Create(getUrl);
getRequest.Headers.Add("Cookie", cookieHeader);
WebResponse getResponse = getRequest.GetResponse();
using (StreamReader sr = new StreamReader(getResponse.GetResponseStream()))
{
    pageSource = sr.ReadToEnd();
}

EDIT:

If you need to view the results of the first POST, you can recover the HTML it returned with:

using (StreamReader sr = new StreamReader(resp.GetResponseStream()))
{
    pageSource = sr.ReadToEnd();
}

Place this directly below cookieHeader = resp.Headers["Set-cookie"]; and then inspect the string held in pageSource.

Is the size of C "int" 2 bytes or 4 bytes?

There's no specific answer. It depends on the platform. It is implementation-defined. It can be 2, 4 or something else.

The idea behind int was that it was supposed to match the natural "word" size on the given platform: 16 bit on 16-bit platforms, 32 bit on 32-bit platforms, 64 bit on 64-bit platforms, you get the idea. However, for backward compatibility purposes some compilers prefer to stick to 32-bit int even on 64-bit platforms.

The time of 2-byte int is long gone though (16-bit platforms?) unless you are using some embedded platform with 16-bit word size. Your textbooks are probably very old.

Two models in one view in ASP MVC 3

You can use the presentation pattern http://martinfowler.com/eaaDev/PresentationModel.html

This presentation "View" model can contain both Person and Order, this new
class can be the model your view references.

Detecting a long press with Android

option: custom detector class

abstract public class
Long_hold
extends View.OnTouchListener
{
  public@Override boolean
  onTouch(View view, MotionEvent touch)
  {
    switch(touch.getAction())
    {
    case ACTION_DOWN: down(touch); return true;
    case ACTION_MOVE: move(touch);
    }
    return true;
  }

  private long
  time_0;
  private float
  x_0, y_0;

  private void
  down(MotionEvent touch)
  {
    time_0= touch.getEventTime();
    x_0= touch.getX();
    y_0= touch.getY();
  }

  private void
  move(MotionEvent touch)
  {
    if(held_too_short(touch) {return;}
    if(moved_too_much(touch)) {return;}

    long_press(touch);
  }
  abstract protected void
  long_hold(MotionEvent touch);
}

use

private double
moved_too_much(MotionEvent touch)
{
  return Math.hypot(
      x_0 -touch.getX(),
      y_0 -touch.getY()) >TOLERANCE;
}

private double
held_too_short(MotionEvent touch)
{
  return touch.getEventTime()-time_0 <DOWN_PERIOD;
}

where

  • TOLERANCE is the maximum tolerated movement

  • DOWN_PERIOD is the time one has to press

import

static android.view.MotionEvent.ACTION_MOVE;
static android.view.MotionEvent.ACTION_DOWN;

in code

setOnTouchListener(new Long_hold()
  {
  protected@Override boolean
  long_hold(MotionEvent touch)
  {
    /*your code on long hold*/
  }
});

Fit Image into PictureBox

You can set picturebox's SizeMode property to PictureSizeMode.Zoom, this will increase the size of smaller images or decrease the size of larger images to fill the PictureBox

How does the "position: sticky;" property work?

Few more things I've come across:

When your sticky element is a component (angular etc)

  • If the 'sticky' element itself is a component with a custom element-selector, such as an angular component named <app-menu-bar> you will need to add the following to the component's css:

      :host { display: block; }     // or use flexbox
    

or

    app-menu-bar  { display: block; }   // (in the containing component's css)

Safari on iOS in particular seems to require `display:block` even on the root element `app-root` of an angular application or it won't stick.
  • If you are creating a component and defining the css inside the component (shadow DOM / encapsulated styles), make sure the position: sticky is being applied to the 'outer' selector (eg. app-menu-bar in devtools should show the sticky position) and not a top level div within the component. With Angular, this can be achieved with the :host selector in the css for your component.

      :host
      {
          position: sticky;
          display: block;   // this is the same as shown above
          top: 0;
          background: red;    
      }
    

Other

  • If the element following your sticky element has a solid background, you must add the following to stop it from sliding underneath:

      .sticky-element { z-index: 100; }
      .parent-of-sticky-element { position: relative; }
    
  • Your sticky element must be before your content if using top and after it if using bottom.

  • There are complications when using overflow: hidden on your wrapper element – in general it will kill the sticky element inside. Better explained in this question

  • Mobile browsers may disable sticky/fixed positioned items when the onscreen keyboard is visible. I'm not sure of the exact rules (does anybody ever know) but when the keyboard is visible you're looking at a sort of 'window' into the window and you won't easily be able to get things to stick to the actual visible top of the screen.

  • Make sure you have:

    position: sticky;

    and not

    display: sticky;

Misc usability concerns

  • Be cautious if your design calls for for sticking things to the bottom of the screen on mobile devices. On iPhone X for instance they display a narrow line to indicate the swipe region (to get back to the homepage) - and elements inside this region aren't clickable. So if you stick something there be sure to test on iPhone X that users can activate it. A big 'Buy Now' button is no good if people can't click it!
  • If you're advertising on Facebook the webpage is displayed in a 'webview' control within Facebook's mobile apps. Especially when displaying video (where your content begins in the bottom half of the screen only) - they often completely mess up sticky elements by putting your page within a scrollable viewport that actually allows your sticky elements to disappear off the top of the page. Be sure to test in the context of an actual ad and not just in the phone's browser or even Facebook's browser which can all behave differently.

Get bottom and right position of an element

You can use the .position() for this

var link = $(element);
var position = link.position(); //cache the position
var right = $(window).width() - position.left - link.width();
var bottom = $(window).height() - position.top - link.height();

DataTable, How to conditionally delete rows

Here's a one-liner using LINQ and avoiding any run-time evaluation of select strings:

someDataTable.Rows.Cast<DataRow>().Where(
    r => r.ItemArray[0] == someValue).ToList().ForEach(r => r.Delete());

Twitter API returns error 215, Bad Authentication Data

You need to send customerKey and customerSecret to Zend_Service_Twitter

$twitter = new Zend_Service_Twitter(array(
                'consumerKey' => $this->consumer_key,
                'consumerSecret' => $this->consumer_secret,
                'username' => $user->screenName,
                'accessToken' => unserialize($user->token)
));

How to customize the back button on ActionBar

I had the same issue of Action-bar Home button icon direction,because of miss managing of Icon in Gradle Resource directory icon

like in Arabic Gradle resource directory you put icon in x-hdpi and in English Gradle resource same icon name you put in different density folder like xx-hdpi ,so that in APK there will be two same icon names in different directories,so your device will pick density dependent icon may be RTL or LTR

How to write a cron that will run a script every day at midnight?

from the man page

linux$ man -S 5 crontab

   cron(8) examines cron entries once every minute.

   The time and date fields are:

          field          allowed values
          -----          --------------
          minute         0-59
          hour           0-23
          day of month   1-31
          month          1-12 (or names, see below)
          day of week    0-7 (0 or 7 is Sun, or use names)
   ...
   # run five minutes after midnight, every day
   5 0 * * *       $HOME/bin/daily.job >> $HOME/tmp/out 2>&1
   ...

It is good to note the special "nicknames" that can be used (documented in the man page), particularly "@reboot" which has no time and date alternative.

   # Run once after reboot.
   @reboot         /usr/local/sbin/run_only_once_after_reboot.sh

You can also use this trick to run your cron job multiple times per minute.

   # Run every minute at 0, 20, and 40 second intervals
   * * * * *       sleep 00; /usr/local/sbin/run_3times_per_minute.sh
   * * * * *       sleep 20; /usr/local/sbin/run_3times_per_minute.sh
   * * * * *       sleep 40; /usr/local/sbin/run_3times_per_minute.sh

To add a cron job, you can do one of three things:

  1. add a command to a user's crontab, as shown above (and from the crontab, section 5, man page).

    • edit a user's crontab as root with crontab -e -u <username>
    • or edit the current user's crontab with just crontab -e
    • You can set the editor with the EDITOR environment variable
      • env EDITOR=nano crontab -e -u <username>
      • or set the value of EDITOR for your entire shell session
        1. export EDITOR=vim
        2. crontab -e
    • Make scripts executable with chmod a+x <file>


  1. create a script/program as a cron job, and add it to the system's anacron /etc/cron.*ly directories

    • anacron /etc/cron.*ly directories:
      • /etc/cron.daily
      • /etc/cron.hourly
      • /etc/cron.monthly
      • /etc/cron.weekly
    • as in:
      • /etc/cron.daily/script_runs_daily.sh
      • chmod a+x /etc/cron.daily/script_runs_daily.sh -- make it executable
    • See also the anacron man page: man anacron
    • Make scripts executable with chmod a+x <file>
    • When do these cron.*ly script run?
      • For RHEL/CentOS 5.x, they are configured in /etc/crontab or /etc/anacrontab to run at a set time
      • RHEL/CentOS 6.x+ and Fedora 17+ Linux systems only define this in /etc/anacrontab, and define cron.hourly in /etc/cron.d/0hourly


  1. Or, One can create system crontables in /etc/cron.d.

    • The previously described crontab syntax (with additionally providing a user to execute each job as) is put into a file, and the file is dropped into the /etc/cron.d directory.
    • These are easy to manage in system packaging (e.g. RPM packages), so may usually be application specific.
    • The syntax difference is that a user must be specified for the cron job after the time/date fields and before the command to execute.
    • The files added to /etc/cron.d do not need to be executable.
    • Here is an example job that is executed as the user someuser, and the use of /bin/bash as the shell is forced.


   File: /etc/cron.d/myapp-cron
   # use /bin/bash to run commands, no matter what /etc/passwd says
   SHELL=/bin/bash
   # Execute a nightly (11:00pm) cron job to scrub application records
   00 23 * * * someuser /opt/myapp/bin/scrubrecords.php

Laravel check if collection is empty

To determine if there are any results you can do any of the following:

if ($mentor->first()) { } 
if (!$mentor->isEmpty()) { }
if ($mentor->count()) { }
if (count($mentor)) { }
if ($mentor->isNotEmpty()) { }

Notes / References

->first()

https://laravel.com/api/5.7/Illuminate/Database/Eloquent/Collection.html#method_first

isEmpty() https://laravel.com/api/5.7/Illuminate/Database/Eloquent/Collection.html#method_isEmpty

->count()

https://laravel.com/api/5.7/Illuminate/Database/Eloquent/Collection.html#method_count

count($mentors) works because the Collection implements Countable and an internal count() method:

https://laravel.com/api/5.7/Illuminate/Database/Eloquent/Collection.html#method_count

isNotEmpty()

https://laravel.com/docs/5.7/collections#method-isnotempty

So what you can do is :

if (!$mentors->intern->employee->isEmpty()) { }

Sending arrays with Intent.putExtra

final static String EXTRA_MESSAGE = "edit.list.message";

Context context;
public void onClick (View view)
{   
    Intent intent = new Intent(this,display.class);
    RelativeLayout relativeLayout = (RelativeLayout) view.getParent();

    TextView textView = (TextView) relativeLayout.findViewById(R.id.textView1);
    String message = textView.getText().toString();

    intent.putExtra(EXTRA_MESSAGE,message);
    startActivity(intent);
}

Duplicate headers received from server

Just put a pair of double quotes around your file name like this:

this.Response.AddHeader("Content-disposition", $"attachment; filename=\"{outputFileName}\"");

Failed to instantiate module [$injector:unpr] Unknown provider: $routeProvider

The ngRoute module is no longer part of the core angular.js file. If you are continuing to use $routeProvider then you will now need to include angular-route.js in your HTML:

<script src="angular.js">
<script src="angular-route.js">

API Reference

You also have to add ngRoute as a dependency for your application:

var app = angular.module('MyApp', ['ngRoute', ...]);

If instead you are planning on using angular-ui-router or the like then just remove the $routeProvider dependency from your module .config() and substitute it with the relevant provider of choice (e.g. $stateProvider). You would then use the ui.router dependency:

var app = angular.module('MyApp', ['ui.router', ...]);

How can I get href links from HTML using Python?

Using requests with BeautifulSoup and Python 3:

import requests 
from bs4 import BeautifulSoup


page = requests.get('http://www.website.com')
bs = BeautifulSoup(page.content, features='lxml')
for link in bs.findAll('a'):
    print(link.get('href'))

How to get jQuery to wait until an effect is finished?

You can specify a callback function:

$(selector).fadeOut('slow', function() {
    // will be called when the element finishes fading out
    // if selector matches multiple elements it will be called once for each
});

Documentation here.

Get the decimal part from a double

 string input = "0.55";
    var regex1 = new System.Text.RegularExpressions.Regex("(?<=[\\.])[0-9]+");
    if (regex1.IsMatch(input))
    {
        string dp= regex1.Match(input ).Value;
    }

What is the different between RESTful and RESTless

Here are summarized the key differences between RESTful and RESTless web services:

1. Protocol

  • RESTful services use REST architectural style,
  • RESTless services use SOAP protocol.

2. Business logic / Functionality

  • RESTful services use URL to expose business logic,
  • RESTless services use the service interface to expose business logic.

3. Security

  • RESTful inherits security from the underlying transport protocols,
  • RESTless defines its own security layer, thus it is considered as more secure.

4. Data format

  • RESTful supports various data formats such as HTML, JSON, text, etc,
  • RESTless supports XML format.

5. Flexibility

  • RESTful is easier and flexible,
  • RESTless is not as easy and flexible.

6. Bandwidth

  • RESTful services consume less bandwidth and resource,
  • RESTless services consume more bandwidth and resources.

Set cURL to use local virtual hosts

Actually, curl has an option explicitly for this: --resolve

Instead of curl -H 'Host: yada.com' http://127.0.0.1/something

use curl --resolve 'yada.com:80:127.0.0.1' http://yada.com/something

What's the difference, you ask?

Among others, this works with HTTPS. Assuming your local server has a certificate for yada.com, the first example above will fail because the yada.com certificate doesn't match the 127.0.0.1 hostname in the URL.

The second example works correctly with HTTPS.

In essence, passing a "Host" header via -H does hack your Host into the header set, but bypasses all of curl's host-specific intelligence. Using --resolve leverages all of the normal logic that applies, but simply pretends the DNS lookup returned the data in your command-line option. It works just like /etc/hosts should.

Note --resolve takes a port number, so for HTTPS you would use

curl --resolve 'yada.com:443:127.0.0.1' https://yada.com/something

How to get the selected value from RadioButtonList?

radiobuttonlist.selected <value> to process with your code.

Min width in window resizing

You can set min-width property of CSS for body tag. Since this property is not supported by IE6, you can write like:

body{
   min-width:1000px;        /* Suppose you want minimum width of 1000px */
   width: auto !important;  /* Firefox will set width as auto */
   width:1000px;            /* As IE6 ignores !important it will set width as 1000px; */
}

Or:

body{
   min-width:1000px; // Suppose you want minimum width of 1000px
   _width: expression( document.body.clientWidth > 1000 ? "1000px" : "auto" ); /* sets max-width for IE6 */
}

installing JDK8 on Windows XP - advapi32.dll error

With JRE 8 on XP there is another way - to use MSI to deploy package.

  • Install JRE 8 x86 on a PC with supported OS
  • Copy c:\Users[USER]\AppData\LocalLow\Sun\Java\jre1.8.0\jre1.8.0.msi and Data1.cab to XP PC and run jre1.8.0.msi

or (silent way, usable in batch file etc..)

for %%I in ("*.msi") do if exist "%%I" msiexec.exe /i %%I /qn EULA=0 SKIPLICENSE=1 PROG=0 ENDDIALOG=0

hash function for string

I have tried these hash functions and got the following result. I have about 960^3 entries, each 64 bytes long, 64 chars in different order, hash value 32bit. Codes from here.

Hash function    | collision rate | how many minutes to finish
==============================================================
MurmurHash3      |           6.?% |                      4m15s
Jenkins One..    |           6.1% |                      6m54s   
Bob, 1st in link |          6.16% |                      5m34s
SuperFastHash    |            10% |                      4m58s
bernstein        |            20% |       14s only finish 1/20
one_at_a_time    |          6.16% |                       7m5s
crc              |          6.16% |                      7m56s

One strange things is that almost all the hash functions have 6% collision rate for my data.

Automatically size JPanel inside JFrame

If the BorderLayout option provided by our friends doesnot work, try adding ComponentListerner to the JFrame and implement the componentResized(event) method. When the JFrame object will be resized, this method will be called. So if you write the the code to set the size of the JPanel in this method, you will achieve the intended result.

Ya, I know this 'solution' is not good but use it as a safety net. ;)

How to analyse the heap dump using jmap in java

VisualVm does not come with Apple JDK. You can use VisualVM Mac Application bundle(dmg) as a separate application, to compensate for that.

How to read data from a zip file without having to unzip the entire file

With .Net Framework 4.5 (using ZipArchive):

using (ZipArchive zip = ZipFile.Open(zipfile, ZipArchiveMode.Read))
    foreach (ZipArchiveEntry entry in zip.Entries)
        if(entry.Name == "myfile")
            entry.ExtractToFile("myfile");

Find "myfile" in zipfile and extract it.

How do I get an element to scroll into view, using jQuery?

Here's a quick jQuery plugin to map the built in browser functionality nicely:

$.fn.ensureVisible = function () { $(this).each(function () { $(this)[0].scrollIntoView(); }); };

...

$('.my-elements').ensureVisible();

Removing single-quote from a string in php

You can substitute in HTML entitiy:

$FileName = preg_replace("/'/", "\&#39;", $UserInput);

What's the difference between a proxy server and a reverse proxy server?

Proxy (Forward Proxy):

When computers on your LAN connect to a proxy server that accesses the Internet. Benefits include only the server being exposed to the Internet. People on the outside are unable to access the computers directly. Forward proxies can improve Internet access for users by caching downloads. They can also be used to restrict access to certain sites. Also, only the proxy server would need a public address, not the clients connecting to it.

Reverse Proxy:

A reverse proxy is the opposite of a forward proxy. Instead it acts as a proxy on behalf of the servers being connected to. Instead of accessing a remote server directly, a user would go through the reverse proxy and get directed to the appropriate server from there. Only the reverse proxy would need an SSL certificate, only one public IP address would be needed, and it can handle load balancing of incoming requests to enhance the overall user experience.

Enter image description here

Image Source: Creating a Forward Proxy Using Application Request Routing

How to align an input tag to the center without specifying the width?

You can also use the tag, this works in divs and everything else:

<center><form></form></center>

This link will help you with the tag:

Why is the <center> tag deprecated in HTML?

python-dev installation error: ImportError: No module named apt_pkg

I'm on Ubuntu 16.04, and upgraded to Python 3.7. Here is the error that I had when trying to add a PPA

    sudo add-apt-repository ppa:ubuntu-toolchain-r/test                                           
Traceback (most recent call last):
  File "/usr/bin/add-apt-repository", line 11, in <module>
    from softwareproperties.SoftwareProperties import SoftwareProperties, shortcut_handler
  File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 27, in <module>
    import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'

I was able to fix this error by making symbolic link with my initial python 3.4 apt_pkg.cpython-34m-x86_64-linux-gnu.so by creating the following symbolic link

sudo ln -s apt_pkg.cpython-34m-x86_64-linux-gnu.so apt_pkg.so

How to solve "java.io.IOException: error=12, Cannot allocate memory" calling Runtime#exec()?

Runtime.getRuntime().exec allocates the process with the same amount of memory as the main. If you had you heap set to 1GB and try to exec then it will allocate another 1GB for that process to run.

How can I save application settings in a Windows Forms application?

I don't like the proposed solution of using web.config or app.config. Try reading your own XML. Have a look at XML Settings Files – No more web.config.

Error message Strict standards: Non-static method should not be called statically in php

If scope resolution :: had to be used outside the class then the respective function or variable should be declared as static

class Foo { 
        //Static variable 
        public static $static_var = 'static variable'; 
        //Static function 
        static function staticValue() { return 'static function'; } 

        //function 
        function Value() { return 'Object'; } 
} 



 echo Foo::$static_var . "<br/>"; echo Foo::staticValue(). "<br/>"; $foo = new Foo(); echo $foo->Value();

MySQL - ERROR 1045 - Access denied

The current root password must be empty. Then under "new root password" enter your password and confirm.

How to format an inline code in Confluence?

As of Confluence 4 and above, typing two curly brackets does not work.

You now need to select Monospace font. Highlight the text you want to change and:

Windows: Ctrl + Shift + M

Mac: Command + Shift + M

Alternatively, you can type a backtick (`) and Confluence will format everything until you type another backtick

Alternatively, next to the bold and italic options, you can click the "more" drop down and select Monospace:

enter image description here

Passing html values into javascript functions

Try: if(parseInt(order)>0){....

Change bundle identifier in Xcode when submitting my first app in IOS

If you are developing a cordova app, make sure to change the version and bundle identifier in the config.xml as well

JQuery show/hide when hover

jquery:

$('div.animalcontent').hide();
$('div').hide();
$('p.animal').bind('mouseover', function() {
    $('div.animalcontent').fadeOut();
    $('#'+$(this).attr('id')+'content').fadeIn();
});  

html:

<p class='animal' id='dog'>dog url</p><div id='dogcontent' class='animalcontent'>Doggiecontent!</div>
<p class='animal' id='cat'>cat url</p><div id='catcontent' class='animalcontent'>Pussiecontent!</div>
<p class='animal' id='snake'>snake url</p><div id='snakecontent'class='animalcontent'>Snakecontent!</div>

-edit-

yeah sure, here you go -- JSFiddle

Setting background colour of Android layout element

Android studio 2.1.2 (or possibly earlier) will let you pick from a color wheel:

Color Wheel in Android Studio

I got this by adding the following to my layout:

android:background="#FFFFFF"

Then I clicked on the FFFFFF color and clicked on the lightbulb that appeared.

How to parse JSON data with jQuery / JavaScript?

var jsonP = "person" : [ { "id" : "1", "name" : "test1" },
  { "id" : "2", "name" : "test2" },
  { "id" : "3", "name" : "test3" },
  { "id" : "4", "name" : "test4" },
  { "id" : "5", "name" : "test5" } ];

var cand = document.getElementById("cand");
var json_arr = [];
$.each(jsonP.person,function(key,value){
    json_arr.push(key+' . '+value.name  + '<br>');
    cand.innerHTML = json_arr;
});

<div id="cand">
</div>

How should I resolve java.lang.IllegalArgumentException: protocol = https host = null Exception?

Might help some else - I came here because I missed putting two // after http:. This is what I had:

http:/abc.my.domain.com:55555/update

Access-control-allow-origin with multiple domains

You can add this code to your asp.net webapi project

in file Global.asax

    protected void Application_BeginRequest()
{
    string origin = Request.Headers.Get("Origin");
    if (Request.HttpMethod == "OPTIONS")
    {
        Response.AddHeader("Access-Control-Allow-Origin", origin);
        Response.AddHeader("Access-Control-Allow-Headers", "*");
        Response.AddHeader("Access-Control-Allow-Methods", "GET,POST,PUT,OPTIONS,DELETE");
        Response.StatusCode = 200;
        Response.End();
    }
    else
    {
        Response.AddHeader("Access-Control-Allow-Origin", origin);
        Response.AddHeader("Access-Control-Allow-Headers", "*");
        Response.AddHeader("Access-Control-Allow-Methods", "GET,POST,PUT,OPTIONS,DELETE");
    }
}

Excel VBA to Export Selected Sheets to PDF

Once you have Selected a group of sheets, you can use Selection

Consider:

Sub luxation()
    ThisWorkbook.Sheets(Array("Sheet1", "Sheet2", "Sheet3")).Select
    Selection.ExportAsFixedFormat _
        Type:=xlTypePDF, _
        Filename:="C:\TestFolder\temp.pdf", _
        Quality:=xlQualityStandard, _
        IncludeDocProperties:=True, _
        IgnorePrintAreas:=False, _
        OpenAfterPublish:=True
End Sub

EDIT#1:

Further testing has reveled that this technique depends on the group of cells selected on each worksheet. To get a comprehensive output, use something like:

Sub Macro1()

   Sheets("Sheet1").Activate
   ActiveSheet.UsedRange.Select
   Sheets("Sheet2").Activate
   ActiveSheet.UsedRange.Select
   Sheets("Sheet3").Activate
   ActiveSheet.UsedRange.Select

   ThisWorkbook.Sheets(Array("Sheet1", "Sheet2", "Sheet3")).Select
   Selection.ExportAsFixedFormat Type:=xlTypePDF, Filename:= _
      "C:\Users\James\Desktop\pdfmaker.pdf", Quality:=xlQualityStandard, _
      IncludeDocProperties:=True, IgnorePrintAreas:=False, OpenAfterPublish:= _
      True
End Sub

Streaming Audio from A URL in Android using MediaPlayer?

Use

 mediaplayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
 mediaplayer.prepareAsync();
 mediaplayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
      @Override
      public void onPrepared(MediaPlayer mp) {
          mediaplayer.start();
      }
 });

Compare two dates with JavaScript

Via Moment.js

Jsfiddle: http://jsfiddle.net/guhokemk/1/

function compare(dateTimeA, dateTimeB) {
    var momentA = moment(dateTimeA,"DD/MM/YYYY");
    var momentB = moment(dateTimeB,"DD/MM/YYYY");
    if (momentA > momentB) return 1;
    else if (momentA < momentB) return -1;
    else return 0;
}

alert(compare("11/07/2015", "10/07/2015"));

The method returns 1 if dateTimeA is greater than dateTimeB

The method returns 0 if dateTimeA equals dateTimeB

The method returns -1 if dateTimeA is less than dateTimeB

Java Date vs Calendar

Date is a simpler class and is mainly there for backward compatibility reasons. If you need to set particular dates or do date arithmetic, use a Calendar. Calendars also handle localization. The previous date manipulation functions of Date have since been deprecated.

Personally I tend to use either time in milliseconds as a long (or Long, as appropriate) or Calendar when there is a choice.

Both Date and Calendar are mutable, which tends to present issues when using either in an API.

iOS Detection of Screenshot?

I found the answer!! Taking a screenshot interrupts any touches that are on the screen. This is why snapchat requires holding to see the picture. Reference: http://tumblr.jeremyjohnstone.com/post/38503925370/how-to-detect-screenshots-on-ios-like-snapchat

How to update json file with python

The issue here is that you've opened a file and read its contents so the cursor is at the end of the file. By writing to the same file handle, you're essentially appending to the file.

The easiest solution would be to close the file after you've read it in, then reopen it for writing.

with open("replayScript.json", "r") as jsonFile:
    data = json.load(jsonFile)

data["location"] = "NewPath"

with open("replayScript.json", "w") as jsonFile:
    json.dump(data, jsonFile)

Alternatively, you can use seek() to move the cursor back to the beginning of the file then start writing, followed by a truncate() to deal with the case where the new data is smaller than the previous.

with open("replayScript.json", "r+") as jsonFile:
    data = json.load(jsonFile)

    data["location"] = "NewPath"

    jsonFile.seek(0)  # rewind
    json.dump(data, jsonFile)
    jsonFile.truncate()

What is a regular expression which will match a valid domain name without a subdomain?

The following regex extracts the sub, root and tld of a given domain:

^(?<domain>(?<domain_sub>(?:[^\/\"\]:\.\s\|\-][^\/\"\]:\.\s\|]*?\.)*?)(?<domain_root>[^\/\"\]:\s\.\|\n]+\.(?<domain_tld>(?:xn--)?[\w-]{2,7}(?:\.[a-zA-Z-]{2,3})*)))$

Tested for the following domains:

* stack.com
* sta-ck.com
* sta---ck.com
* 9sta--ck.com
* sta--ck9.com
* stack99.com
* 99stack.com
* sta99ck.com
* google.com.uk
* google.co.in

* google.com
* maselkowski.pl
* maselkowski.pl
* m.maselkowski.pl
* www.maselkowski.pl.com
* xn--masekowski-d0b.pl
* xn--fiqa61au8b7zsevnm8ak20mc4a87e.xn--fiqs8s

* xn--stackoverflow.com
* stackoverflow.xn--com
* stackoverflow.co.uk

Understanding timedelta

why do I have to pass seconds = uptime to timedelta

Because timedelta objects can be passed seconds, milliseconds, days, etc... so you need to specify what are you passing in (this is why you use the explicit key). Typecasting to int is superfluous as they could also accept floats.

and why does the string casting works so nicely that I get HH:MM:SS ?

It's not the typecasting that formats, is the internal __str__ method of the object. In fact you will achieve the same result if you write:

print datetime.timedelta(seconds=int(uptime))

What does 'const static' mean in C and C++?

It's missing an 'int'. It should be:

const static int foo = 42;

In C and C++, it declares an integer constant with local file scope of value 42.

Why 42? If you don't already know (and it's hard to believe you don't), it's a refernce to the Answer to Life, the Universe, and Everything.

Remove useless zero digits from decimals in PHP

I found this solution is the best:

public function priceFormat(float $price): string
{
    //https://stackoverflow.com/a/14531760/5884988
    $price = $price + 0;
    $split = explode('.', $price);
    return number_format($price, isset($split[1]) ? strlen($split[1]) : 2, ',', '.');
}

Why do Twitter Bootstrap tables always have 100% width?

Bootstrap 3:

Why fight it? Why not simply control your table width using the bootstrap grid?

<div class="row">
    <div class="col-sm-6">
        <table></table>
    </div>
</div>

This will create a table that is half (6 out of 12) of the width of the containing element.

I sometimes use inline styles as per the other answers, but it is discouraged.

Bootstrap 4:

Bootstrap 4 has some nice helper classes for width like w-25, w-50, w-75, w-100, and w-auto. This will make the table 50% width:

<table class="w-50"></table>

Here's the doc: https://getbootstrap.com/docs/4.0/utilities/sizing/

How to select all columns, except one column in pandas?

You can drop columns in index:

df[df.columns.drop('b')]

Output:

          a         c         d
0  0.418762  0.869203  0.972314
1  0.991058  0.594784  0.534366
2  0.407472  0.396664  0.894202
3  0.726168  0.324932  0.906575

How can I get the nth character of a string?

Array notation and pointer arithmetic can be used interchangeably in C/C++ (this is not true for ALL the cases but by the time you get there, you will find the cases yourself). So although str is a pointer, you can use it as if it were an array like so:

char char_E = str[1];
char char_L1 = str[2];
char char_O = str[4];

...and so on. What you could also do is "add" 1 to the value of the pointer to a character str which will then point to the second character in the string. Then you can simply do:

str = str + 1; // makes it point to 'E' now
char myChar =  *str;

I hope this helps.

How to track untracked content?

I just had the same problem. The reason was because there was a subfolder that contained a ".git" folder. Removing it made git happy.

jQuery remove special characters from string and more

replace(/[^a-z0-9\s]/gi, '') will filter the string down to just alphanumeric values and replace(/[_\s]/g, '-') will replace underscores and spaces with hyphens:

str.replace(/[^a-z0-9\s]/gi, '').replace(/[_\s]/g, '-')

Source for Regex: RegEx for Javascript to allow only alphanumeric

Here is a demo: http://jsfiddle.net/vNfrk/

How can I search for a multiline pattern in a file?

@Marcin: awk example non-greedy:

awk '{if ($0 ~ /Start pattern/) {triggered=1;}if (triggered) {print; if ($0 ~ /End pattern/) { exit;}}}' filename

Why does the Google Play store say my Android app is incompatible with my own device?

If you're here in 2020 and you think the device receiving the error message should be compatible:

Several other major apps have run into this including Instagram (1B+ installs) and Clash of Clans (100M+ installs). It appears to be an issue with Google's Android operating system.

To fix the “your device is not compatible with this version” error message, try clearing the Google Play Store cache, and then data. Next, restart the Google Play Store and try installing the app again.

[https://support.getupside.com/hc/en-us/articles/226667067--Device-not-compatible-error-message-in-Google-Play-Store]

Here is a link to Google's official support page that you can link to your users on how to clear the cache: https://support.google.com/googleplay/answer/7513003

Insert an element at a specific index in a list and return the updated list

Use the Python list insert() method. Usage:

#Syntax

The syntax for the insert() method -

list.insert(index, obj)

#Parameters

  • index - This is the Index where the object obj need to be inserted.
  • obj - This is the Object to be inserted into the given list.

#Return Value This method does not return any value, but it inserts the given element at the given index.

Example:

a = [1,2,4,5]

a.insert(2,3)

print(a)

Returns [1, 2, 3, 4, 5]

What's the console.log() of java?

The Log class:

API for sending log output.

Generally, use the Log.v() Log.d() Log.i() Log.w() and Log.e() methods.

The order in terms of verbosity, from least to most is ERROR, WARN, INFO, DEBUG, VERBOSE. Verbose should never be compiled into an application except during development. Debug logs are compiled in but stripped at runtime. Error, warning and info logs are always kept.

Outside of Android, System.out.println(String msg) is used.

Get selected text from a drop-down list (select box) using jQuery

the following worked for me:

$.trim($('#dropdownId option:selected').html())

Calling Python in Java?

This gives a pretty good overview over the current options. Some of which are named in other answers. Jython is not usable until they decide to implement Python 3.x and many of the other projects are coming form the python side and want to access java. But there are a few options still, to name something which has not been named yet: gRPC

Difference between Apache CXF and Axis

The advantages of CXF:

  1. CXF supports for WS-Addressing, WS-Policy, WS-RM, WS-Security and WS-I BasicProfile.
  2. CXF implements JAX-WS API (according by JAX-WS 2.0 TCK).
  3. CXF has better integration with Spring and other frameworks.
  4. CXF has high extensibility in terms of their interceptor strategy.
  5. CXF has more configurable feature via the API instead of cumbersome XML files.
  6. CXF has Bindings:SOAP,REST/HTTP, and its Data Bindings support JAXB 2.0,Aegis, by default it use JAXB 2.0 and more close Java standard specification.
  7. CXF has abundant toolkits, e.g. Java to WSDL, WSDL to Java, XSD to WSDL, WSDL to XML, WSDL to SOAP, WSDL to Service.

The advantages of Axis2:

  1. Axis2 also supports WS-RM, WS-Security, and WS-I BasicProfile except for WS-Policy, I expect it will be supported in an upcoming version.
  2. Axis has more options for data bindings for your choose
  3. Axis2 supports multiple languages—including C/C++ version and Java version.
  4. Axis2 supports a wider range of data bindings, including XMLBeans, JiBX, JaxMe and JaxBRI as well as its own native data binding, ADB. longer history than CXF.

In Summary: From above advantage items, it brings us to a good thoughts to compare Axis2 and CXF on their own merits. they all have different well-developed areas in a certain field, CXF is very configurable, integratable and has rich tool kits supported and close to Java community, Axis2 has taken an approach that makes it in many ways resemble an application server in miniature. it is across multiple programming languages. because its Independence, Axis2 lends itself towards web services that stand alone, independent of other applications, and offers a wide variety of functionality.

As a developer, we need to accord our perspective to choose the right one, whichever framework you choose, you’ll have the benefit of an active and stable open source community. In terms of performance, I did a test based the same functionality and configed in the same web container, the result shows that CXF performed little bit better than Axis2, the single case may not exactly reflect their capabilities and performance.

In some research articles, it reveals that Axis2's proprietary ADB databinding is a bit faster than CXF since it don’t have additional feature(WS-Security). Apache AXIS2 is relatively most used framework but Apache CXF scores over other Web Services Framework comparatively considering ease of development, current industry trend, performance, overall scorecard and other features (unless there is Web Services Orchestration support is explicitly needed, which is not required here)

How to create virtual column using MySQL SELECT?

Something like:

SELECT id, email, IF(active = 1, 'enabled', 'disabled') AS account_status FROM users

This allows you to make operations and show it as columns.

EDIT:

you can also use joins and show operations as columns:

SELECT u.id, e.email, IF(c.id IS NULL, 'no selected', c.name) AS country
FROM users u LEFT JOIN countries c ON u.country_id = c.id

Scripting SQL Server permissions

declare @DBRoleName varchar(40) = 'yourUserName'
SELECT 'GRANT ' + dbprm.permission_name + ' ON ' + OBJECT_SCHEMA_NAME(major_id) + '.' + OBJECT_NAME(major_id) + ' TO ' + dbrol.name + char(13) COLLATE Latin1_General_CI_AS
from sys.database_permissions dbprm
join sys.database_principals dbrol on
dbprm.grantee_principal_id = dbrol.principal_id
where dbrol.name = @DBRoleName

http://www.sqlserver-dba.com/2014/10/how-to-script-database-role-permissions-and-securables.html

I found this to be an excellent solution for generating a script to replicate access between environments

Conda: Installing / upgrading directly from github

I found a reference to this in condas issues. The following should now work.

name: sample_env
channels:
dependencies:
   - requests
   - bokeh>=0.10.0
   - pip:
     - git+https://github.com/pythonforfacebook/facebook-sdk.git

How to convert string to boolean php

filter_var($string, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);

$string = 1; // true
$string ='1'; // true
$string = 'true'; // true
$string = 'trUe'; // true
$string = 'TRUE'; // true
$string = 0; // false
$string = '0'; // false
$string = 'false'; // false
$string = 'False'; // false
$string = 'FALSE'; // false
$string = 'sgffgfdg'; // null

You must specify

FILTER_NULL_ON_FAILURE
otherwise you'll get always false even if $string contains something else.

Gradient text color

I don't exactly know how the stop stuff works. But I've got a gradient text example. Maybe this will help you out!

_you can also add more colors to the gradient if you want or just select other colors from the color generator

_x000D_
_x000D_
.rainbow2 {_x000D_
    background-image: -webkit-linear-gradient(left, #E0F8F7, #585858, #fff); /* For Chrome and Safari */_x000D_
    background-image:    -moz-linear-gradient(left, #E0F8F7, #585858, #fff); /* For old Fx (3.6 to 15) */_x000D_
    background-image:     -ms-linear-gradient(left, #E0F8F7, #585858, #fff); /* For pre-releases of IE 10*/_x000D_
    background-image:      -o-linear-gradient(left, #E0F8F7, #585858, #fff); /* For old Opera (11.1 to 12.0) */_x000D_
    background-image:         linear-gradient(to right, #E0F8F7, #585858, #fff); /* Standard syntax; must be last */_x000D_
    color:transparent;_x000D_
    -webkit-background-clip: text;_x000D_
    background-clip: text;_x000D_
}_x000D_
.rainbow {_x000D_
_x000D_
  background-image: -webkit-gradient( linear, left top, right top, color-stop(0, #f22), color-stop(0.15, #f2f), color-stop(0.3, #22f), color-stop(0.45, #2ff), color-stop(0.6, #2f2),color-stop(0.75, #2f2), color-stop(0.9, #ff2), color-stop(1, #f22) );_x000D_
  background-image: gradient( linear, left top, right top, color-stop(0, #f22), color-stop(0.15, #f2f), color-stop(0.3, #22f), color-stop(0.45, #2ff), color-stop(0.6, #2f2),color-stop(0.75, #2f2), color-stop(0.9, #ff2), color-stop(1, #f22) );_x000D_
  color:transparent;_x000D_
  -webkit-background-clip: text;_x000D_
  background-clip: text;_x000D_
}
_x000D_
<span class="rainbow">Rainbow text</span>_x000D_
<br />_x000D_
<span class="rainbow2">No rainbow text</span>
_x000D_
_x000D_
_x000D_

How do you close/hide the Android soft keyboard using Java?

Update: I don't know why this solution is not work any more ( I just tested on Android 23). Please use the solution of Saurabh Pareek instead. Here it is:

InputMethodManager imm = (InputMethodManager) getSystemService(Activity.INPUT_METHOD_SERVICE);
//Hide:
imm.toggleSoftInput(InputMethodManager.HIDE_IMPLICIT_ONLY, 0);
//Show
imm.toggleSoftInput(InputMethodManager.SHOW_IMPLICIT, 0);

Old answer:

//Show soft-keyboard:
getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
//hide keyboard :
 getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);

How do I write the 'cd' command in a makefile?

Like this:

target:
    $(shell cd ....); \
    # ... commands execution in this directory
    # ... no need to go back (using "cd -" or so)
    # ... next target will be automatically in prev dir

Good luck!

How to manage a redirect request after a jQuery Ajax call

I like Timmerz's method with a slight twist of lemon. If you ever get returned contentType of text/html when you're expecting JSON, you are most likely being redirected. In my case, I just simply reload the page, and it gets redirected to the login page. Oh, and check that the jqXHR status is 200, which seems silly, because you are in the error function, right? Otherwise, legitimate error cases will force an iterative reload (oops)

$.ajax(
   error:  function (jqXHR, timeout, message) {
    var contentType = jqXHR.getResponseHeader("Content-Type");
    if (jqXHR.status === 200 && contentType.toLowerCase().indexOf("text/html") >= 0) {
        // assume that our login has expired - reload our current page
        window.location.reload();
    }

});

How to run a Python script in the background even after I logout SSH?

You could also use GNU screen which just about every Linux/Unix system should have.

If you are on Ubuntu/Debian, its enhanced variant byobu is rather nice too.

What does "int 0x80" mean in assembly code?

Keep in mind that 0x80 = 80h = 128

You can see here that INT is just one of the many instructions (actually the Assembly Language representation (or should I say 'mnemonic') of it) that exists in the x86 instruction set. You can also find more information about this instruction in Intel's own manual found here.

To summarize from the PDF:

INT n/INTO/INT 3—Call to Interrupt Procedure

The INT n instruction generates a call to the interrupt or exception handler specified with the destination operand. The destination operand specifies a vector from 0 to 255, encoded as an 8-bit unsigned intermediate value. The INT n instruction is the general mnemonic for executing a software-generated call to an interrupt handler.

As you can see 0x80 is the destination operand in your question. At this point the CPU knows that it should execute some code that resides in the Kernel, but what code? That is determined by the Interrupt Vector in Linux.

One of the most useful DOS software interrupts was interrupt 0x21. By calling it with different parameters in the registers (mostly ah and al) you could access various IO operations, string output and more.

Most Unix systems and derivatives do not use software interrupts, with the exception of interrupt 0x80, used to make system calls. This is accomplished by entering a 32-bit value corresponding to a kernel function into the EAX register of the processor and then executing INT 0x80.

Take a look at this please where other available values in the interrupt handler tables are shown:

enter image description here

As you can see the table points the CPU to execute a system call. You can find the Linux System Call table here.

So by moving the value 0x1 to EAX register and calling the INT 0x80 in your program, you can make the process go execute the code in Kernel which will stop (exit) the current running process (on Linux, x86 Intel CPU).

A hardware interrupt must not be confused with a software interrupt. Here is a very good answer on this regard.

This also is good source.

ERROR 1130 (HY000): Host '' is not allowed to connect to this MySQL server

Your root account, and this statement applies to any account, may only have been added with localhost access (which is recommended).

You can check this with:

SELECT host FROM mysql.user WHERE User = 'root';

If you only see results with localhost and 127.0.0.1, you cannot connect from an external source. If you see other IP addresses, but not the one you're connecting from - that's also an indication.

You will need to add the IP address of each system that you want to grant access to, and then grant privileges:

CREATE USER 'root'@'ip_address' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'root'@'ip_address';

If you see %, well then, there's another problem altogether as that is "any remote source". If however you do want any/all systems to connect via root, use the % wildcard to grant access:

CREATE USER 'root'@'%' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%';

Finally, reload the permissions, and you should be able to have remote access:

FLUSH PRIVILEGES;

App.settings - the Angular way?

If you are using , there is yet another option:

Angular CLI provides environment files in src/environments (default ones are environment.ts (dev) and environment.prod.ts (production)).

Note that you need to provide the config parameters in all environment.* files, e.g.,

environment.ts:

export const environment = {
  production: false,
  apiEndpoint: 'http://localhost:8000/api/v1'
};

environment.prod.ts:

export const environment = {
  production: true,
  apiEndpoint: '__your_production_server__'
};

and use them in your service (the correct environment file is chosen automatically):

api.service.ts

// ... other imports
import { environment } from '../../environments/environment';

@Injectable()
export class ApiService {     

  public apiRequest(): Observable<MyObject[]> {
    const path = environment.apiEndpoint + `/objects`;
    // ...
  }

// ...
}

Read more on application environments on Github (Angular CLI version 6) or in the official Angular guide (version 7).

cancelling a handler.postdelayed process

In case you do have multiple inner/anonymous runnables passed to same handler, and you want to cancel all at same event use

handler.removeCallbacksAndMessages(null);

As per documentation,

Remove any pending posts of callbacks and sent messages whose obj is token. If token is null, all callbacks and messages will be removed.

VueJS conditionally add an attribute for an element

You can pass boolean by coercing it, put !! before the variable.

let isRequired = '' || null || undefined
<input :required="!!isRequired"> // it will coerce value to respective boolean 

But I would like to pull your attention for the following case where the receiving component has defined type for props. In that case, if isRequired has defined type to be string then passing boolean make it type check fails and you will get Vue warning. To fix that you may want to avoid passing that prop, so just put undefined fallback and the prop will not sent to component

let isValue = false
<any-component
  :my-prop="isValue ? 'Hey I am when the value exist' : undefined"
/>

Explanation

I have been through the same problem, and tried above solutions !! Yes, I don't see the prop but that actually does not fulfils what required here.

My problem -

let isValid = false
<any-component
  :my-prop="isValue ? 'Hey I am when the value exist': false"
/>

In the above case, what I expected is not having my-prop get passed to the child component - <any-conponent/> I don't see the prop in DOM but In my <any-component/> component, an error pops out of prop type check failure. As in the child component, I am expecting my-prop to be a String but it is boolean.

myProp : {
 type: String,
 required: false,
 default: ''
}

Which means that child component did receive the prop even if it is false. Tweak here is to let the child component to take the default-value and also skip the check. Passed undefined works though!

<any-component
  :my-prop="isValue ? 'Hey I am when the value exist' : undefined"
/>
 

This works and my child prop is having the default value.

Detecting Windows or Linux?

Useful simple class are forked by me on: https://gist.github.com/kiuz/816e24aa787c2d102dd0

public class OSValidator {

    private static String OS = System.getProperty("os.name").toLowerCase();

    public static void main(String[] args) {

        System.out.println(OS);

        if (isWindows()) {
            System.out.println("This is Windows");
        } else if (isMac()) {
            System.out.println("This is Mac");
        } else if (isUnix()) {
            System.out.println("This is Unix or Linux");
        } else if (isSolaris()) {
            System.out.println("This is Solaris");
        } else {
            System.out.println("Your OS is not support!!");
        }
    }

    public static boolean isWindows() {
        return OS.contains("win");
    }

    public static boolean isMac() {
        return OS.contains("mac");
    }

    public static boolean isUnix() {
        return (OS.contains("nix") || OS.contains("nux") || OS.contains("aix"));
    }

    public static boolean isSolaris() {
        return OS.contains("sunos");
    }
    public static String getOS(){
        if (isWindows()) {
            return "win";
        } else if (isMac()) {
            return "osx";
        } else if (isUnix()) {
            return "uni";
        } else if (isSolaris()) {
            return "sol";
        } else {
            return "err";
        }
    }

}

restrict edittext to single line

in XML File add this properties in Edit Text

 android:maxLines="1"

oracle SQL how to remove time from date

When you convert your string to a date you need to match the date mask to the format in the string. This includes a time element, which you need to remove with truncation:

select 
    p1.PA_VALUE as StartDate,
    p2.PA_VALUE as EndDate
from WP_Work p 
LEFT JOIN PARAMETER p1 on p1.WP_ID=p.WP_ID AND p1.NAME = 'StartDate'
LEFT JOIN PARAMETER p2 on p2.WP_ID=p.WP_ID AND p2.NAME = 'Date_To'
WHERE p.TYPE = 'EventManagement2'
AND trunc(TO_DATE(p1.PA_VALUE, 'DD-MM-YYYY HH24:MI')) >= TO_DATE('25/10/2012', 'DD/MM/YYYY')
AND trunc(TO_DATE(p2.PA_VALUE, 'DD-MM-YYYY HH24:MI')) <= TO_DATE('26/10/2012', 'DD/MM/YYYY')

how to change color of TextinputLayout's label and edittext underline android

Based on Fedor Kazakov and others answers, I created a default config.

styles.xml

<resources>

    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
    </style>

    <style name="Widget.Design.TextInputLayout" parent="AppTheme">
        <item name="hintTextAppearance">@style/AppTheme.TextFloatLabelAppearance</item>
        <item name="errorTextAppearance">@style/AppTheme.TextErrorAppearance</item>
        <item name="counterTextAppearance">@style/TextAppearance.Design.Counter</item>
        <item name="counterOverflowTextAppearance">@style/TextAppearance.Design.Counter.Overflow</item>
    </style>

    <style name="AppTheme.TextFloatLabelAppearance" parent="TextAppearance.Design.Hint">
        <!-- Floating label appearance here -->
        <item name="android:textColor">@color/colorAccent</item>
        <item name="android:textSize">20sp</item>
    </style>

    <style name="AppTheme.TextErrorAppearance" parent="TextAppearance.Design.Error">
        <!-- Error message appearance here -->
        <item name="android:textColor">#ff0000</item>
        <item name="android:textSize">20sp</item>
    </style>

</resources>

activity_layout.xml

<android.support.design.widget.TextInputLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <android.support.v7.widget.AppCompatEditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Text hint here"
        android:text="5,2" />

</android.support.design.widget.TextInputLayout>

Focused:

Focused

Without focus:

Without focus

Error message:

enter image description here

How to insert current datetime in postgresql insert query

timestamp (or date or time columns) do NOT have "a format".

Any formatting you see is applied by the SQL client you are using.


To insert the current time use current_timestamp as documented in the manual:

INSERT into "Group" (name,createddate) 
VALUES ('Test', current_timestamp);

To display that value in a different format change the configuration of your SQL client or format the value when SELECTing the data:

select name, to_char(createddate, ''yyyymmdd hh:mi:ss tt') as created_date
from "Group"

For psql (the default command line client) you can configure the display format through the configuration parameter DateStyle: https://www.postgresql.org/docs/current/static/runtime-config-client.html#GUC-DATESTYLE

C# SQL Server - Passing a list to a stored procedure

The only way I'm aware of is building CSV list and then passing it as string. Then, on SP side, just split it and do whatever you need.

Programmatically Check an Item in Checkboxlist where text is equal to what I want

I tried adding dynamically created ListItem and assigning the selected value.

foreach(var item in yourListFromDB)
{
 ListItem listItem = new ListItem();
 listItem.Text = item.name;
 listItem.Value = Convert.ToString(item.value);
 listItem.Selected=item.isSelected;                 
  checkedListBox1.Items.Add(listItem);
}
checkedListBox1.DataBind();

avoid using binding the DataSource as it will not bind the checked/unchecked from DB.

How to open the second form?

If you need to show Form2 as a modal dialog, from within Form1 do:

var form2 = new Form2();
if (form2.ShowDialog() == DialogResult.OK) 
{
    // process results here
}

A modal dialog will retain focus while it is open; it will set the parent windows (Form1) "in the background" until it is closed, which is quite a common practice for settings windows.

How to get address of a pointer in c/c++?

you can use this

in C

int a =10;
int *p = &a;     
int **pp = &p;
printf("%u",&p);

in C++

cout<<p;

How to find all tables that have foreign keys that reference particular table.column and have values for those foreign keys?

Listing all foreign keys in a db including description

    SELECT  
    i1.CONSTRAINT_NAME, i1.TABLE_NAME,i1.COLUMN_NAME,
    i1.REFERENCED_TABLE_SCHEMA,i1.REFERENCED_TABLE_NAME, i1.REFERENCED_COLUMN_NAME,
    i2.UPDATE_RULE, i2.DELETE_RULE 
    FROM   
    information_schema.KEY_COLUMN_USAGE AS i1  
    INNER JOIN 
    information_schema.REFERENTIAL_CONSTRAINTS AS i2 
    ON i1.CONSTRAINT_NAME = i2.CONSTRAINT_NAME 
    WHERE i1.REFERENCED_TABLE_NAME IS NOT NULL  
    AND  i1.TABLE_SCHEMA  ='db_name';

restricting to a specific column in a table table

AND i1.table_name = 'target_tb_name' AND i1.column_name = 'target_col_name'

Difference between 2 dates in seconds

$timeFirst  = strtotime('2011-05-12 18:20:20');
$timeSecond = strtotime('2011-05-13 18:20:20');
$differenceInSeconds = $timeSecond - $timeFirst;

You will then be able to use the seconds to find minutes, hours, days, etc.

Event handler not working on dynamic content

You are missing the selector in the .on function:

.on(eventType, selector, function)

This selector is very important!

http://api.jquery.com/on/

If new HTML is being injected into the page, select the elements and attach event handlers after the new HTML is placed into the page. Or, use delegated events to attach an event handler

See jQuery 1.9 .live() is not a function for more details.

How can I get file extensions with JavaScript?

Don't forget that some files can have no extension, so:

var parts = filename.split('.');
return (parts.length > 1) ? parts.pop() : '';

When adding a Javascript library, Chrome complains about a missing source map, why?

While, the fix as per Valeri works, but its only for tfjs.

If you're expecting for body-pix or any other tensor-flow/models, you would be facing the same. It is an open issue too and the team is working on the fix!

https://github.com/dequelabs/axe-core/issues/1977

But, if you don't have problem in degrading the version (if anyone wants to use body-pix) from latest docs, below both links works fine as I've tested the same:

<script src="https://cdn.jsdelivr.net/npm/@tensorflow/[email protected]/dist/tf.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/@tensorflow-models/[email protected]"></script> 

How to add /usr/local/bin in $PATH on Mac

In MAC OS Catalina, this are the steps that worked for me, all the above solutions did help but didn't solve my problem.

  1. check node --version, still the old one in use.
  2. cd ~/
  3. atom .bash_profile
  4. Remove the $PATH pointing to old node version, in my case it was /usr/local/bin/node/@node8
  5. Add & save this to $PATH instead "export PATH=$PATH:/usr/local/git/bin:/usr/local/bin"
  6. Close all applications using node (terminal, simulator, browser expo etc)
  7. restart terminal and check node --version

How to drop a database with Mongoose?

To empty a particular collection in a database:

model.remove(function(err, p){
    if(err){ 
        throw err;
    } else{
        console.log('No Of Documents deleted:' + p);
    }
});

Note:

  1. Choose a model referring to particular schema(schema of collection you wish to delete).
  2. This operation will not delete collection name from database.
  3. This deletes all the documents in a collection.

Error : java.lang.NoSuchMethodError: org.objectweb.asm.ClassWriter.<init>(I)V

There is a lot of incompatibility between different versions of cglib and lots of poor advice that can be googled on this subject (use ancient versions of cglib-nodeb, etc). After wrestling with this nonsense for 3 days with an ancient version of Spring (2.5.6)I have discovered:

  • if Spring is throwing exceptions about NoSuchMethodError based on Enhancer from cglib missing setInterceptDuringConstruction(boolean), check your dependencies in maven (Dependency Hierarchy tab should list all the versions of cglib your project is polluted by). You probably have a dependency that is bringing in a pre-2.2 version of cglib, which Spring Cglib2AopProxy will grab Enhancer from to do the proxying. Add 2.2+ version to your dependencies but make sure to put in exclusions for these other versions. If you don't it will just keep blowing up.
  • Make sure you have a high enough version of cglib in the current project's maven dependencies but beware of picking too high a version because then you'll get IncompatibleClassChangeError(s) instead.
  • Verify that your pom changes have made it into the project correctly by doing a maven update on the project in question and then looking at Project > preferences > Java Build Path > Libraries > Maven Dependencies. If you see the wrong cglib versions in there, time to edit the pom again.

This declaration has no storage class or type specifier in C++

You can declare an object of a class in another Class,that's possible but you cant initialize that object. For that you need to do something like this :--> (inside main)

Orderbook o1;
o1.m.check(side)

but that would be unnecessary. Keeping things short :-

You can't call functions inside a Class

How to determine programmatically the current active profile using Spring boot

It doesn't matter is your app Boot or just raw Spring. There is just enough to inject org.springframework.core.env.Environment to your bean.

@Autowired
private Environment environment;
....

this.environment.getActiveProfiles();

How to align input forms in HTML

<form>
    <div>
        <label for='username'>UserName</label>
        <input type='text' name='username' id='username' value=''>  
    </div>
</form>

In the CSS you have to declare both label and input as display: inline-block and give width according to your requirements. Hope this will help you. :)

how to get the ipaddress of a virtual box running on local machine

Login to virtual machine use below command to check ip address. (anyone will work)

  1. ifconfig
  2. ip addr show

If you used NAT for your virtual machine settings(your machine ip will be 10.0.2.15), then you have to use port forwarding to connect to machine. IP address will be 127.0.0.1

If you used bridged networking/Host only networking, then you will have separate Ip address. Use that IP address to connect virtual machine

Reading a .txt file using Scanner class in Java

At first check the file address, it must be beside your .java file or in any address that you define in classpath environment variable. When you check this then try below.

  1. you must use a file name by it's extension in File object constructor, as an example:

    File myFile = new File("test.txt");

  2. but there is a better way to use it inside Scanner object by pass the filename absolute address, as an example:

    Scanner sc = new Scanner(Paths.get("test.txt"));

in this way you must import java.nio.file.Paths as well.

Creating stored procedure with declare and set variables

You should try this syntax - assuming you want to have @OrderID as a parameter for your stored procedure:

CREATE PROCEDURE dbo.YourStoredProcNameHere
   @OrderID INT
AS
BEGIN
 DECLARE @OrderItemID AS INT
 DECLARE @AppointmentID AS INT
 DECLARE @PurchaseOrderID AS INT
 DECLARE @PurchaseOrderItemID AS INT
 DECLARE @SalesOrderID AS INT
 DECLARE @SalesOrderItemID AS INT

 SELECT @OrderItemID = OrderItemID 
 FROM [OrderItem] 
 WHERE OrderID = @OrderID

 SELECT @AppointmentID = AppoinmentID 
 FROM [Appointment] 
 WHERE OrderID = @OrderID

 SELECT @PurchaseOrderID = PurchaseOrderID 
 FROM [PurchaseOrder] 
 WHERE OrderID = @OrderID

END

OF course, that only works if you're returning exactly one value (not multiple values!)

Is nested function a good approach when required by only one function?

Generally, no, do not define functions inside functions.

Unless you have a really good reason. Which you don't.

Why not?

What is a really good reason to define functions inside functions?

When what you actually want is a dingdang closure.

Not able to install Python packages [SSL: TLSV1_ALERT_PROTOCOL_VERSION]

@Anupam's solution worked for me. However, I had to use sudo and specify the exact location of my virtual Python environment:

curl https://bootstrap.pypa.io/get-pip.py | sudo /Users/{your user name}/{path to python}/bin/python

Submit form on pressing Enter with AngularJS

Angular supports this out of the box. Have you tried ngSubmit on your form element?

<form ng-submit="myFunc()" ng-controller="mycontroller">
   <input type="text" ng-model="name" />
    <br />
    <input type="text" ng-model="email" />
</form>

EDIT: Per the comment regarding the submit button, see Submitting a form by pressing enter without a submit button which gives the solution of:

<input type="submit" style="position: absolute; left: -9999px; width: 1px; height: 1px;"/>

If you don't like the hidden submit button solution, you'll need to bind a controller function to the Enter keypress or keyup event. This normally requires a custom directive, but the AngularUI library has a nice keypress solution set up already. See http://angular-ui.github.com/

After adding the angularUI lib, your code would be something like:

<form ui-keypress="{13:'myFunc($event)'}">
  ... input fields ...
</form>

or you can bind the enter keypress to each individual field.

Also, see this SO questions for creating a simple keypres directive: How can I detect onKeyUp in AngularJS?

EDIT (2014-08-28): At the time this answer was written, ng-keypress/ng-keyup/ng-keydown did not exist as native directives in AngularJS. In the comments below @darlan-alves has a pretty good solution with:

<input ng-keyup="$event.keyCode == 13 && myFunc()"... />