Programs & Examples On #Silverlight

Silverlight is Microsoft's cross-browser, cross platform plug-in for media experiences and rich interactive applications.

Format Date/Time in XAML in Silverlight

<TextBlock Text="{Binding Date, StringFormat='{}{0:MM/dd/yyyy a\\t h:mm tt}'}" />

will return you

04/07/2011 at 1:28 PM (-04)

How to programmatically set the Image source

try this

PictureBox picture = new PictureBox
        {
            Name = "pictureBox",
            Size = new Size(100, 50),
            Location = new Point(14, 17),
            Image = Image.FromFile(@"c:\Images\test.jpg"),
            SizeMode = PictureBoxSizeMode.CenterImage
        };
p.Controls.Add(picture);

Difference between SelectedItem, SelectedValue and SelectedValuePath

SelectedItem is an object. SelectedValue and SelectedValuePath are strings.

for example using the ListBox:

if you say give me listbox1.SelectedValue it will return the text of the currently selected item.

string value = listbox1.SelectedValue;

if you say give me listbox1.SelectedItem it will give you the entire object.

ListItem item = listbox1.SelectedItem;
string value = item.value;

Get current index from foreach loop

Use Enumerable.Select<TSource, TResult> Method (IEnumerable<TSource>, Func<TSource, Int32, TResult>)

list = list.Cast<object>().Select( (v, i) => new {Value= v, Index = i});

foreach(var row in list)
{
    bool IsChecked = (bool)((CheckBox)DataGridDetail.Columns[0].GetCellContent(row.Value)).IsChecked;
    row.Index ...
}

How do I space out the child elements of a StackPanel?

My approach inherits StackPanel.

Usage:

<Controls:ItemSpacer Grid.Row="2" Orientation="Horizontal" Height="30" CellPadding="15,0">
    <Label>Test 1</Label>
    <Label>Test 2</Label>
    <Label>Test 3</Label>
</Controls:ItemSpacer>

All that's needed is the following short class:

using System.Windows;
using System.Windows.Controls;
using System;

namespace Controls
{
    public class ItemSpacer : StackPanel
    {
        public static DependencyProperty CellPaddingProperty = DependencyProperty.Register("CellPadding", typeof(Thickness), typeof(ItemSpacer), new FrameworkPropertyMetadata(default(Thickness), FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, OnCellPaddingChanged));
        public Thickness CellPadding
        {
            get
            {
                return (Thickness)GetValue(CellPaddingProperty);
            }
            set
            {
                SetValue(CellPaddingProperty, value);
            }
        }
        private static void OnCellPaddingChanged(DependencyObject Object, DependencyPropertyChangedEventArgs e)
        {
            ((ItemSpacer)Object).SetPadding();
        }

        private void SetPadding()
        {
            foreach (UIElement Element in Children)
            {
                (Element as FrameworkElement).Margin = this.CellPadding;
            }
        }

        public ItemSpacer()
        {
            this.LayoutUpdated += PART_Host_LayoutUpdated;
        }

        private void PART_Host_LayoutUpdated(object sender, System.EventArgs e)
        {
            this.SetPadding();
        }
    }
}

Value does not fall within the expected range

In case of WSS 3.0 recently I experienced same issue. It was because of column that was accessed from code was not present in the wss list.

Could not find an implementation of the query pattern

Hi easiest way to do this is to convert this IEnumerable into a Queryable

If it is a queryable, then performing queries becomes easy.

Please check this code:

var result = (from s in _ctx.ScannedDatas.AsQueryable()
                              where s.Data == scanData
                              select s.Id).FirstOrDefault();
                return "Match Found";

Make sure you include System.Linq. This way your error will be resolved.

How to automatically select all text on focus in WPF TextBox?

In App.xaml file:

<Application.Resources>
    <Style TargetType="TextBox">
        <EventSetter Event="GotKeyboardFocus" Handler="TextBox_GotKeyboardFocus"/>
    </Style>
</Application.Resources>

In App.xaml.cs file:

private void TextBox_GotKeyboardFocus(Object sender, KeyboardFocusChangedEventArgs e)
{
    ((TextBox)sender).SelectAll();
}

With this code you reach all TextBox in your application.

The HTTP request is unauthorized with client authentication scheme 'Ntlm'

1) I had to do the following with my configuration: (Add BackConnectionHostNames or Disable Loopback Check) http://support.microsoft.com/kb/896861

2) I was working off a dev system on an isolated dev network. I had gotten it working using the dev system's computer name in the URL to the web service, but when I modified the URL to the URL that would be used in production (rather than the computer name), I started getting the NTLM error.

3) I noticed the security log showed that the service account failing to login with an error similar to the one in the MSDN article.

4) Adding the BackConnectionHostNames made it so I could log into the server via a browser running on the server, but the service account still had NTLM errors when trying to authenticate for the web services. I wound up disabling the loop back check and that fixed it for me.

How to trigger event when a variable's value is changed?

The .NET framework actually provides an interface that you can use for notifying subscribers when a property has changed: System.ComponentModel.INotifyPropertyChanged. This interface has one event PropertyChanged. Its usually used in WPF for binding but I have found it useful in business layers as a way to standardize property change notification.

In terms of thread safety I would put a lock under in the setter so that you don't run into any race conditions.

Here are my thoughts in code :) :

public class MyClass : INotifyPropertyChanged
{
    private object _lock;

    public int MyProperty
    {
        get
        {
            return _myProperty;
        }
        set
        {
            lock(_lock)
            {
                //The property changed event will get fired whenever
                //the value changes. The subscriber will do work if the value is
                //1. This way you can keep your business logic outside of the setter
                if(value != _myProperty)
                {
                    _myProperty = value;
                    NotifyPropertyChanged("MyProperty");
                }
            }
        }
    }

    private NotifyPropertyChanged(string propertyName)
    {
        //Raise PropertyChanged event
    }
    public event PropertyChangedEventHandler PropertyChanged;
}


public class MySubscriber
{
    private MyClass _myClass;        

    void PropertyChangedInMyClass(object sender, PropertyChangedEventArgs e)
    {
        switch(e.PropertyName)
        {
            case "MyProperty":
                DoWorkOnMyProperty(_myClass.MyProperty);
                break;
        }
    }

    void DoWorkOnMyProperty(int newValue)
    {
        if(newValue == 1)
        {
             //DO WORK HERE
        }
    }
}

Hope this is helpful :)

How to prevent colliders from passing through each other?

Try setting the models to environment and static. That fix my issue.

What's the difference between size_t and int in C++?

From the friendly Wikipedia:

The stdlib.h and stddef.h header files define a datatype called size_t which is used to represent the size of an object. Library functions that take sizes expect them to be of type size_t, and the sizeof operator evaluates to size_t.

The actual type of size_t is platform-dependent; a common mistake is to assume size_t is the same as unsigned int, which can lead to programming errors, particularly as 64-bit architectures become more prevalent.

Also, check Why size_t matters

Compiling and Running Java Code in Sublime Text 2

I followed a post in this thread and got it working perfectly:

Make the bat file with the following, and save it anywhere in your PATH. I suggest C:\Program Files\Java\jdk*\bin\ to keep everything together.

@ECHO OFF
cd %~dp1
javac %~nx1
java %~n1

then edit C:\Users\your_user_name\AppData\Roaming\Sublime Text 2\Packages\Java\JavaC.sublime-build, the contents will be

{
   "cmd": ["javac", "$file"],
   "file_regex": "^(...*?):([0-9]*):?([0-9]*)",
   "selector": "source.java"
}

replace "javac" with the name of your bat file (for instance, javacexec.bat) and save it.

Unable to create Genymotion Virtual Device

I just ran into this problem too, so just in case anyone needs it: The reason why it needs admin privileges is probably because of your settings on where it store the virtual device.. Go to Settings - Virtual Box - and change your virtual devices storage area. I got mine set to something like \Program Files\Genymotion, that's why it needs Admin privileges. I only blanked the field, clicked ok, and it got set to the default which is in my home directory.. After that no need to run as admin anymore..

(I need 50 reputations to comment, so had to use this answer..)

Error 80040154 (Class not registered exception) when initializing VCProjectEngineObject (Microsoft.VisualStudio.VCProjectEngine.dll)

There are not many good reasons this would fail, especially the regsvr32 step. Run dumpbin /exports on that dll. If you don't see DllRegisterServer then you've got a corrupt install. It should have more side-effects, you wouldn't be able to build C/C++ projects anymore.

One standard failure mode is running this on a 64-bit operating system. This is 32-bit unmanaged code, you would indeed get the 'class not registered' exception. Project + Properties, Build tab, change Platform Target to x86.

Split data frame string column into multiple columns

The subject is almost exhausted, I 'd like though to offer a solution to a slightly more general version where you don't know the number of output columns, a priori. So for example you have

before = data.frame(attr = c(1,30,4,6), type=c('foo_and_bar','foo_and_bar_2', 'foo_and_bar_2_and_bar_3', 'foo_and_bar'))
  attr                    type
1    1             foo_and_bar
2   30           foo_and_bar_2
3    4 foo_and_bar_2_and_bar_3
4    6             foo_and_bar

We can't use dplyr separate() because we don't know the number of the result columns before the split, so I have then created a function that uses stringr to split a column, given the pattern and a name prefix for the generated columns. I hope the coding patterns used, are correct.

split_into_multiple <- function(column, pattern = ", ", into_prefix){
  cols <- str_split_fixed(column, pattern, n = Inf)
  # Sub out the ""'s returned by filling the matrix to the right, with NAs which are useful
  cols[which(cols == "")] <- NA
  cols <- as.tibble(cols)
  # name the 'cols' tibble as 'into_prefix_1', 'into_prefix_2', ..., 'into_prefix_m' 
  # where m = # columns of 'cols'
  m <- dim(cols)[2]

  names(cols) <- paste(into_prefix, 1:m, sep = "_")
  return(cols)
}

We can then use split_into_multiple in a dplyr pipe as follows:

after <- before %>% 
  bind_cols(split_into_multiple(.$type, "_and_", "type")) %>% 
  # selecting those that start with 'type_' will remove the original 'type' column
  select(attr, starts_with("type_"))

>after
  attr type_1 type_2 type_3
1    1    foo    bar   <NA>
2   30    foo  bar_2   <NA>
3    4    foo  bar_2  bar_3
4    6    foo    bar   <NA>

And then we can use gather to tidy up...

after %>% 
  gather(key, val, -attr, na.rm = T)

   attr    key   val
1     1 type_1   foo
2    30 type_1   foo
3     4 type_1   foo
4     6 type_1   foo
5     1 type_2   bar
6    30 type_2 bar_2
7     4 type_2 bar_2
8     6 type_2   bar
11    4 type_3 bar_3

Location of hibernate.cfg.xml in project?

You can put the file "hibernate.cfg.xml" to the src folder (src\hibernate.cfg.xml) and then init the config as the code below:

Configuration configuration = new Configuration();          
sessionFactory =configuration.configure().buildSessionFactory();

How do I make CMake output into a 'bin' dir?

Use the EXECUTABLE_OUTPUT_PATH CMake variable to set the needed path. For details, refer to the online CMake documentation:

CMake 2.8.8 Documentation

What are file descriptors, explained in simple terms?

File descriptors

  • To Kernel all open files are referred to by file descriptors.
  • A file descriptor is a non - negative integer.
  • When we open an existing or create a new file, the kernel returns a file descriptor to a process.
  • When we want to read or write on a file, we identify the file with file descriptor that was retuned by open or create, as an argument to either read or write.
  • Each UNIX process has 20 file descriptors and it disposal, numbered 0 through 19 but it was extended to 63 by many systems.
  • The first three are already opened when the process begins 0: The standard input 1: The standard output 2: The standard error output
  • When the parent process forks a process, the child process inherits the file descriptors of the parent

iOS - Calling App Delegate method from ViewController

This is how I do it.

[[[UIApplication sharedApplication] delegate] performSelector:@selector(nameofMethod)];

Dont forget to import.

#import "AppDelegate.h"

How to force input to only allow Alpha Letters?

<input type="text" name="field" maxlength="8"
    onkeypress="return onlyAlphabets(event,this);" />

function onlyAlphabets(e, t) {
            try {
                if (window.event) {
                    var charCode = window.event.keyCode;
                }
                else if (e) {
                    var charCode = e.which;
                }
                else { return true; }
                if ((charCode > 64 && charCode < 91) || (charCode > 96 && charCode < 123))
                    return true;
                else
                    return false;
            }
            catch (err) {
                alert(err.Description);
            }
        }

Center text in div?

If you have text inside a <div>:

text-align: center;
vertical-align: middle;
display: table-cell;

Printing without newline (print 'a',) prints a space, how to remove?

If you want them to show up one at a time, you can do this:

import time
import sys
for i in range(20):
    sys.stdout.write('a')
    sys.stdout.flush()
    time.sleep(0.5)

sys.stdout.flush() is necessary to force the character to be written each time the loop is run.

Android SDK folder taking a lot of disk space. Do we need to keep all of the System Images?

I had 20.8 GB in the C:\Users\ggo\AppData\Local\Android\Sdk\system-images folder (6 android images: - android-10 - android-15 - android-21 - android-23 - android-25 - android-26 ).

I have compressed the C:\Users\ggo\AppData\Local\Android\Sdk\system-images folder.

Now it takes only 4.65 GB.

C:\Users\ggo\AppData\Local\Android\Sdk\system-images

I did not encountered any problem up to now...

Compression seems to vary from 2/3 to 6, sometimes much more:

android-10

android-23

android-25

android-26

Cannot apply indexing with [] to an expression of type 'System.Collections.Generic.IEnumerable<>

The IEnumerable<T> interface does not include an indexer, you're probably confusing it with IList<T>

If the object really is an IList<T> (e.g. List<T> or an array T[]), try making the reference to it of type IList<T> too.

Otherwise, you can use myEnumerable.ElementAt(index) which uses the Enumerable.ElementAt extension method. This should work for all IEnumerable<T>s . Note that unless the (run-time) object implements IList<T>, this will cause all of the first index + 1 items to be enumerated, with all but the last being discarded.

EDIT: As an explanation, IEnumerable<T> is simply an interface that represents "that which exposes an enumerator." A concrete implementation may well be some sort of in-memory list that does allow fast-access by index, or it may not. For instance, it could be a collection that cannot efficiently satisfy such a query, such as a linked-list (as mentioned by James Curran). It may even be no sort of in-memory data-structure at all, such as an iterator, where items are generated ('yielded') on demand, or by an enumerator that fetches the items from some remote data-source. Because IEnumerable<T> must support all these cases, indexers are excluded from its definition.

Making authenticated POST requests with Spring RestTemplate for Android

Ok found the answer. exchange() is the best way. Oddly the HttpEntity class doesn't have a setBody() method (it has getBody()), but it is still possible to set the request body, via the constructor.

// Create the request body as a MultiValueMap
MultiValueMap<String, String> body = new LinkedMultiValueMap<String, String>();     

body.add("field", "value");

// Note the body object as first parameter!
HttpEntity<?> httpEntity = new HttpEntity<Object>(body, requestHeaders);

ResponseEntity<MyModel> response = restTemplate.exchange("/api/url", HttpMethod.POST, httpEntity, MyModel.class);

PHP - If variable is not empty, echo some html code

isset will return true even if the variable is "". isset returns false only if a variable is null. What you should be doing:

if (!empty($web)) {
    // foo
}

This will check that he variable is not empty.

Hope this helps

How to git-cherry-pick only changes to certain files?

Cherry pick is to pick changes from a specific "commit". The simplest solution is to pick all changes of certain files is to use

 git checkout source_branch <paths>...

In example:

$ git branch
* master
  twitter_integration
$ git checkout twitter_integration app/models/avatar.rb db/migrate/20090223104419_create_avatars.rb test/unit/models/avatar_test.rb test/functional/models/avatar_test.rb
$ git status
# On branch master
# Changes to be committed:
#   (use "git reset HEAD <file>..." to unstage)
#
#   new file:   app/models/avatar.rb
#   new file:   db/migrate/20090223104419_create_avatars.rb
#   new file:   test/functional/models/avatar_test.rb
#   new file:   test/unit/models/avatar_test.rb
#
$ git commit -m "'Merge' avatar code from 'twitter_integration' branch"
[master]: created 4d3e37b: "'Merge' avatar code from 'twitter_integration' branch"
4 files changed, 72 insertions(+), 0 deletions(-)
create mode 100644 app/models/avatar.rb
create mode 100644 db/migrate/20090223104419_create_avatars.rb
create mode 100644 test/functional/models/avatar_test.rb
create mode 100644 test/unit/models/avatar_test.rb

Sources and full explanation http://jasonrudolph.com/blog/2009/02/25/git-tip-how-to-merge-specific-files-from-another-branch/

UPDATE:

With this method, git will not MERGE the file, it will just override any other change done on the destination branch. You will need to merge the changes manually:

$ git diff HEAD filename

How to show all of columns name on pandas dataframe?

The easiest way I've found is just

list(df.columns)

Personally I wouldn't want to change the globals, it's not that often I want to see all the columns names.

How to print (using cout) a number in binary form?

The easiest way is probably to create an std::bitset representing the value, then stream that to cout.

#include <bitset>
...

char a = -58;
std::bitset<8> x(a);
std::cout << x << '\n';

short c = -315;
std::bitset<16> y(c);
std::cout << y << '\n';

How to make an unaware datetime timezone aware in python

I agree with the previous answers, and is fine if you are ok to start in UTC. But I think it is also a common scenario for people to work with a tz aware value that has a datetime that has a non UTC local timezone.

If you were to just go by name, one would probably infer replace() will be applicable and produce the right datetime aware object. This is not the case.

the replace( tzinfo=... ) seems to be random in its behaviour. It is therefore useless. Do not use this!

localize is the correct function to use. Example:

localdatetime_aware = tz.localize(datetime_nonaware)

Or a more complete example:

import pytz
from datetime import datetime
pytz.timezone('Australia/Melbourne').localize(datetime.now())

gives me a timezone aware datetime value of the current local time:

datetime.datetime(2017, 11, 3, 7, 44, 51, 908574, tzinfo=<DstTzInfo 'Australia/Melbourne' AEDT+11:00:00 DST>)

Find duplicate characters in a String and count the number of occurances using Java

Finding the duplicates in a String:

Example 1 : Using HashMap

public class a36 {
    public static void main(String[] args) {
        String a = "Gini Rani";
        fix(a);
    }//main
    public static void fix(String a ){
        Map<Character ,Integer> map = new HashMap<>();
        for (int i = 0; i <a.length() ; i++ ) {
        char ch = a.charAt(i);
                map.put(ch , map.getOrDefault(ch,0) +1 );
        }//for

       List<Character> list = new ArrayList<>();
       Set<Map.Entry<Character ,Integer> > entrySet = map.entrySet();

       for (  Map.Entry<Character ,Integer> entry : entrySet) {
             list.add( entry.getKey()  ); 

             System.out.printf(  " %s : %d %n" ,  entry.getKey(), entry.getValue()           );
       }//for
       System.out.println("Duplicate elements => " + list);

    }//fix
}

Example 2 : using Arrays.stream() in Java 8

public class a37 {
    public static void main(String[] args) {
        String aa = "Protijayi Gini";
        String[] stringarray = aa.split("");

    Map<String , Long> map =  Arrays.stream(stringarray)
        .collect(Collectors.groupingBy(c -> c , Collectors.counting()));
        map.forEach( (k, v) -> System.out.println(k + " : "+ v)        );
    }
}

Clearing <input type='file' /> using jQuery


$("input[type=file]").wrap("<div id='fileWrapper'/>");
$("#fileWrapper").append("<div id='duplicateFile'   style='display:none'>"+$("#fileWrapper").html()+"</div>");
$("#fileWrapper").html($("#duplicateFile").html());

How to sort multidimensional array by column?

You can use the sorted method with a key.

sorted(a, key=lambda x : x[1])

Passing data between view controllers

Passing data back from ViewController 2 (destination) to viewController 1 (source) is the more interesting thing. Assuming you use storyBoard, these are all the ways I found out:

  • Delegate
  • Notification
  • User defaults
  • Singleton

Those were discussed here already.

I found there are more ways:

Using Block callbacks:

Use it in the prepareForSegue method in the VC1

NextViewController *destinationVC = (NextViewController *) segue.destinationViewController;
[destinationVC setDidFinishUsingBlockCallback:^(NextViewController *destinationVC)
{
    self.blockLabel.text = destination.blockTextField.text;
}];

Using storyboards Unwind (Exit)

Implement a method with a UIStoryboardSegue argument in VC 1,like this one:

-(IBAction)UnWindDone:(UIStoryboardSegue *)segue { }

In the storyBoard, hook the "return" button to the green Exit button (Unwind) of the vc. Now you have a segue that "goes back" so you can use the destinationViewController property in the prepareForSegue of VC2 and change any property of VC1 before it goes back.

  • Another option of using storyboards Undwind (Exit) - you can use the method you wrote in VC1

     -(IBAction)UnWindDone:(UIStoryboardSegue *)segue {
         NextViewController *nextViewController = segue.sourceViewController;
         self.unwindLabel.text = nextViewController.unwindPropertyPass;
     }
    

And in the prepareForSegue of VC1 you can change any property you want to share.

In both unwind options, you can set the tag property of the button and check it in the prepareForSegue.

Twig for loop for arrays with keys

These are extended operations (e.g., sort, reverse) for one dimensional and two dimensional arrays in Twig framework:

1D Array

Without Key Sort and Reverse

{% for key, value in array_one_dimension %}
    <div>{{ key }}</div>
    <div>{{ value }}</div>
{% endfor %}

Key Sort

{% for key, value in array_one_dimension|keys|sort %}
    <div>{{ key }}</div>
    <div>{{ value }}</div>
{% endfor %}

Key Sort and Reverse

{% for key, value in array_one_dimension|keys|sort|reverse %}
    <div>{{ key }}</div>
    <div>{{ value }}</div>
{% endfor %}

2D Arrays

Without Key Sort and Reverse

{% for key_a, value_a in array_two_dimension %}
    {% for key_b, value_b in array_two_dimension[key_a] %}
        <div>{{ key_b }}</div>
        <div>{{ value_b }}</div>
    {% endfor %}
{% endfor %}

Key Sort on Outer Array

{% for key_a, value_a in array_two_dimension|keys|sort %}
    {% for key_b, value_b in array_two_dimension[key_a] %}
        <div>{{ key_b }}</div>
        <div>{{ value_b }}</div>
    {% endfor %}
{% endfor %}

Key Sort on Both Outer and Inner Arrays

{% for key_a, value_a in array_two_dimension|keys|sort %}
    {% for key_b, value_b in array_two_dimension[key_a]|keys|sort %}
        <div>{{ key_b }}</div>
        <div>{{ value_b }}</div>
    {% endfor %}
{% endfor %}

Key Sort on Outer Array & Key Sort and Reverse on Inner Array

{% for key_a, value_a in array_two_dimension|keys|sort %}
    {% for key_b, value_b in array_two_dimension[key_a]|keys|sort|reverse %}
        <div>{{ key_b }}</div>
        <div>{{ value_b }}</div>
    {% endfor %}
{% endfor %}

Key Sort and Reverse on Outer Array & Key Sort on Inner Array

{% for key_a, value_a in array_two_dimension|keys|sort|reverse %}
    {% for key_b, value_b in array_two_dimension[key_a]|keys|sort %}
        <div>{{ key_b }}</div>
        <div>{{ value_b }}</div>
    {% endfor %}
{% endfor %}

Key Sort and Reverse on Both Outer and Inner Array

{% for key_a, value_a in array_two_dimension|keys|sort|reverse %}
    {% for key_b, value_b in array_two_dimension[key_a]|keys|sort|reverse %}
        <div>{{ key_b }}</div>
        <div>{{ value_b }}</div>
    {% endfor %}
{% endfor %}

Importing Pandas gives error AttributeError: module 'pandas' has no attribute 'core' in iPython Notebook

I face similar issue while importing TensorFlow. If you are using Tensorflow which uses Pandas library, I suggest restarting your kernel of Anaconda. This works for me.

What is the difference between function and procedure in PL/SQL?

  1. we can call a stored procedure inside stored Procedure,Function within function ,StoredProcedure within function but we can not call function within stored procedure.
  2. we can call function inside select statement.
  3. We can return value from function without passing output parameter as a parameter to the stored procedure.

This is what the difference i found. Please let me know if any .

Reference jars inside a jar

Add the jar files to your library(if using netbeans) and modify your manifest's file classpath as follows:

Class-Path: lib/derby.jar lib/derbyclient.jar lib/derbynet.jar lib/derbytools.jar

a similar answer exists here

java.lang.ClassNotFoundException: org.eclipse.core.runtime.adaptor.EclipseStarter

I had the same issue.

just removed all my worskspace:

C:\Users\<name>\.<eclipse similar name>

changing permission for files and folder recursively using shell command in mac

You can just use the -R (recursive) flag.

chmod -R 777 /Users/Test/Desktop/PATH

How to Change Font Size in drawString Java

Because you can't count on a particular font being available, a good approach is to derive a new font from the current font. This gives you the same family, weight, etc. just larger...

Font currentFont = g.getFont();
Font newFont = currentFont.deriveFont(currentFont.getSize() * 1.4F);
g.setFont(newFont);

You can also use TextAttribute.

Map<TextAttribute, Object> attributes = new HashMap<>();

attributes.put(TextAttribute.FAMILY, currentFont.getFamily());
attributes.put(TextAttribute.WEIGHT, TextAttribute.WEIGHT_SEMIBOLD);
attributes.put(TextAttribute.SIZE, (int) (currentFont.getSize() * 1.4));
myFont = Font.getFont(attributes);

g.setFont(myFont);

The TextAttribute method often gives one even greater flexibility. For example, you can set the weight to semi-bold, as in the example above.

One last suggestion... Because the resolution of monitors can be different and continues to increase with technology, avoid adding a specific amount (such as getSize()+2 or getSize()+4) and consider multiplying instead. This way, your new font is consistently proportional to the "current" font (getSize() * 1.4), and you won't be editing your code when you get one of those nice 4K monitors.

Simpler way to create dictionary of separate variables?

Maybe I'm overthinking this but..

str_l = next((k for k,v in locals().items() if id(l) == id(v)))


>>> bar = True
>>> foo = False
>>> my_dict=dict(bar=bar, foo=foo)
>>> next((k for k,v in locals().items() if id(bar) == id(v)))
'bar'
>>> next((k for k,v in locals().items() if id(foo) == id(v)))
'foo'
>>> next((k for k,v in locals().items() if id(my_dict) == id(v)))
'my_dict'

How do you specify table padding in CSS? ( table, not cell padding )

CSS doesn't really allow you to do this on a table level. Generally, I specify cellspacing="3" when I want to achieve this effect. Obviously not a css solution, so take it for what it's worth.

Get size of a View in React Native

for me setting the Dimensions to use % is what worked for me width:'100%'

Find distance between two points on map using Google Map API V2

You can use the following method that will give you accurate result

public double CalculationByDistance(LatLng StartP, LatLng EndP) {
        int Radius = 6371;// radius of earth in Km
        double lat1 = StartP.latitude;
        double lat2 = EndP.latitude;
        double lon1 = StartP.longitude;
        double lon2 = EndP.longitude;
        double dLat = Math.toRadians(lat2 - lat1);
        double dLon = Math.toRadians(lon2 - lon1);
        double a = Math.sin(dLat / 2) * Math.sin(dLat / 2)
                + Math.cos(Math.toRadians(lat1))
                * Math.cos(Math.toRadians(lat2)) * Math.sin(dLon / 2)
                * Math.sin(dLon / 2);
        double c = 2 * Math.asin(Math.sqrt(a));
        double valueResult = Radius * c;
        double km = valueResult / 1;
        DecimalFormat newFormat = new DecimalFormat("####");
        int kmInDec = Integer.valueOf(newFormat.format(km));
        double meter = valueResult % 1000;
        int meterInDec = Integer.valueOf(newFormat.format(meter));
        Log.i("Radius Value", "" + valueResult + "   KM  " + kmInDec
                + " Meter   " + meterInDec);

        return Radius * c;
    }

Enable Hibernate logging

I answer to myself. As suggested by Vadzim, I must consider the jboss-logging.xml file and insert these lines:

<logger category="org.hibernate">
     <level name="TRACE"/>
</logger>

Instead of DEBUG level I wrote TRACE. Now don't look only the console but open the server.log file (debug messages aren't sent to the console but you can configure this mode!).

Alarm Manager Example

MainActivity.java

package com.example.alarmexample;  

import android.app.Activity;  
import android.app.AlarmManager;  
import android.app.PendingIntent;  
import android.content.Intent;  
import android.os.Bundle;  
import android.view.View;  
import android.view.View.OnClickListener;  
import android.widget.Button;  
import android.widget.EditText;  
import android.widget.Toast;  

public class MainActivity extends Activity {  
Button b1;  

    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_main); 

        startAlert();  

}   public void startAlert() { 
        int timeInSec = 2;

        Intent intent = new Intent(this, MyBroadcastReceiver.class);  
        PendingIntent pendingIntent = PendingIntent.getBroadcast(  
                                      this.getApplicationContext(), 234, intent, 0);  
        AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);  
        alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + (timeInSec * 1000), pendingIntent);  
        Toast.makeText(this, "Alarm set to after " + i + " seconds",Toast.LENGTH_LONG).show();  
    }  

}

MyBroadcastReceiver.java

package com.example.alarmexample;  

import android.content.BroadcastReceiver;  
import android.content.Context;  
import android.content.Intent;  
import android.media.MediaPlayer;  
import android.widget.Toast;  

public class MyBroadcastReceiver extends BroadcastReceiver {  
    MediaPlayer mp;  
    @Override  
    public void onReceive(Context context, Intent intent) {  
        mp=MediaPlayer.create(context, R.raw.alarm);  
        mp.start();  
        Toast.makeText(context, "Alarm", Toast.LENGTH_LONG).show();  
    }  
}  

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>  
<manifest xmlns:android="http://schemas.android.com/apk/res/android"  
    package="com.example.alarmexample" >  

    <uses-permission android:name="android.permission.VIBRATE" />  


    <application  
        android:allowBackup="true"  
        android:icon="@drawable/ic_launcher"  
        android:label="@string/app_name"  
        android:theme="@style/AppTheme" >  

        <activity  
            android:name="com.example.alarmexample.MainActivity"  
            android:label="@string/app_name" >  
            <intent-filter>  
                <action android:name="android.intent.action.MAIN" />  

                <category android:name="android.intent.category.LAUNCHER" />  
            </intent-filter>  
        </activity>  

        <receiver android:name="MyBroadcastReceiver" >  
        </receiver>  
    </application>  

</manifest>  

How do you get a list of the names of all files present in a directory in Node.js?

if someone still search for this, i do this:

_x000D_
_x000D_
import fs from 'fs';_x000D_
import path from 'path';_x000D_
_x000D_
const getAllFiles = dir =>_x000D_
    fs.readdirSync(dir).reduce((files, file) => {_x000D_
        const name = path.join(dir, file);_x000D_
        const isDirectory = fs.statSync(name).isDirectory();_x000D_
        return isDirectory ? [...files, ...getAllFiles(name)] : [...files, name];_x000D_
    }, []);
_x000D_
_x000D_
_x000D_

and its work very good for me

How to write DataFrame to postgres table?

Faster option:

The following code will copy your Pandas DF to postgres DB much faster than df.to_sql method and you won't need any intermediate csv file to store the df.

Create an engine based on your DB specifications.

Create a table in your postgres DB that has equal number of columns as the Dataframe (df).

Data in DF will get inserted in your postgres table.

from sqlalchemy import create_engine
import psycopg2 
import io

if you want to replace the table, we can replace it with normal to_sql method using headers from our df and then load the entire big time consuming df into DB.

engine = create_engine('postgresql+psycopg2://username:password@host:port/database')

df.head(0).to_sql('table_name', engine, if_exists='replace',index=False) #drops old table and creates new empty table

conn = engine.raw_connection()
cur = conn.cursor()
output = io.StringIO()
df.to_csv(output, sep='\t', header=False, index=False)
output.seek(0)
contents = output.getvalue()
cur.copy_from(output, 'table_name', null="") # null values become ''
conn.commit()

Failed binder transaction when putting an bitmap dynamically in a widget

You can compress the bitmap as an byte's array and then uncompress it in another activity, like this.

Compress!!

        ByteArrayOutputStream stream = new ByteArrayOutputStream();
        bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
        byte[] bytes = stream.toByteArray(); 
        setresult.putExtra("BMP",bytes);

Uncompress!!

        byte[] bytes = data.getByteArrayExtra("BMP");
        Bitmap bmp = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);

What does it mean to bind a multicast (UDP) socket?

To bind a UDP socket when receiving multicast means to specify an address and port from which to receive data (NOT a local interface, as is the case for TCP acceptor bind). The address specified in this case has a filtering role, i.e. the socket will only receive datagrams sent to that multicast address & port, no matter what groups are subsequently joined by the socket. This explains why when binding to INADDR_ANY (0.0.0.0) I received datagrams sent to my multicast group, whereas when binding to any of the local interfaces I did not receive anything, even though the datagrams were being sent on the network to which that interface corresponded.

Quoting from UNIX® Network Programming Volume 1, Third Edition: The Sockets Networking API by W.R Stevens. 21.10. Sending and Receiving

[...] We want the receiving socket to bind the multicast group and port, say 239.255.1.2 port 8888. (Recall that we could just bind the wildcard IP address and port 8888, but binding the multicast address prevents the socket from receiving any other datagrams that might arrive destined for port 8888.) We then want the receiving socket to join the multicast group. The sending socket will send datagrams to this same multicast address and port, say 239.255.1.2 port 8888.

Negative regex for Perl string pattern match

What's wrong with using two regexs (or three)? This makes your intentions more clear and may even improve your performance:

if ($string =~ /^(Clinton|Reagan)/i && $string !~ /Bush/i) { ... }

if (($string =~ /^Clinton/i || $string =~ /^Reagan/i)
        && $string !~ /Bush/i) {
    print "$string\n"
}

Multiple conditions in ngClass - Angular 4

I hope this is one of the basic conditional classes

Solution: 1

<section [ngClass]="(condition)? 'class1 class2 ... classN' : 'another class1 ... classN' ">

Solution 2

<section [ngClass]="(condition)? 'class1 class2 ... classN' : '(condition)? 'class1 class2 ... classN':'another class' ">

Solution 3

<section [ngClass]="'myclass': condition, 'className2': condition2">

How to Sign an Already Compiled Apk

You use jarsigner to sign APK's. You don't have to sign with the original keystore, just generate a new one. Read up on the details: http://developer.android.com/guide/publishing/app-signing.html

How do I create delegates in Objective-C?

//1.
//Custom delegate 
@protocol TB_RemovedUserCellTag <NSObject>

-(void)didRemoveCellWithTag:(NSInteger)tag;

@end

//2.
//Create a weak reference in a class where you declared the delegate
@property(weak,nonatomic)id <TB_RemovedUserCellTag> removedCellTagDelegate;

//3. 
// use it in the class
  [self.removedCellTagDelegate didRemoveCellWithTag:self.tag];

//4. import the header file in the class where you want to conform to the protocol
@interface MyClassUsesDelegate ()<TB_RemovedUserCellTag>

@end

//5. Implement the method in the class .m -(void)didRemoveCellWithTag:(NSInteger)tag { NSLog@("Tag %d",tag);

}

What do parentheses surrounding an object/function/class declaration mean?

...but what about the previous round parenteses surrounding all the function declaration?

Specifically, it makes JavaScript interpret the 'function() {...}' construct as an inline anonymous function expression. If you omitted the brackets:

function() {
    alert('hello');
}();

You'd get a syntax error, because the JS parser would see the 'function' keyword and assume you're starting a function statement of the form:

function doSomething() {
}

...and you can't have a function statement without a function name.

function expressions and function statements are two different constructs which are handled in very different ways. Unfortunately the syntax is almost identical, so it's not just confusing to the programmer, even the parser has difficulty telling which you mean!

Meaning of numbers in "col-md-4"," col-xs-1", "col-lg-2" in Bootstrap

Applies to Bootstrap 3 only.

Ignoring the letters (xs, sm, md, lg) for now, I'll start with just the numbers...

  • the numbers (1-12) represent a portion of the total width of any div
  • all divs are divided into 12 columns
  • so, col-*-6 spans 6 of 12 columns (half the width), col-*-12 spans 12 of 12 columns (the entire width), etc

So, if you want two equal columns to span a div, write

<div class="col-xs-6">Column 1</div>
<div class="col-xs-6">Column 2</div>

Or, if you want three unequal columns to span that same width, you could write:

<div class="col-xs-2">Column 1</div>
<div class="col-xs-6">Column 2</div>
<div class="col-xs-4">Column 3</div>

You'll notice the # of columns always add up to 12. It can be less than twelve, but beware if more than 12, as your offending divs will bump down to the next row (not .row, which is another story altogether).

You can also nest columns within columns, (best with a .row wrapper around them) such as:

<div class="col-xs-6">
  <div class="row">
    <div class="col-xs-4">Column 1-a</div>
    <div class="col-xs-8">Column 1-b</div>
  </div>
</div>
<div class="col-xs-6">
  <div class="row">
    <div class="col-xs-2">Column 2-a</div>
    <div class="col-xs-10">Column 2-b</div>
  </div>
</div>

Each set of nested divs also span up to 12 columns of their parent div. NOTE: Since each .col class has 15px padding on either side, you should usually wrap nested columns in a .row, which has -15px margins. This avoids duplicating the padding and keeps the content lined up between nested and non-nested col classes.

-- You didn't specifically ask about the xs, sm, md, lg usage, but they go hand-in-hand so I can't help but touch on it...

In short, they are used to define at which screen size that class should apply:

  • xs = extra small screens (mobile phones)
  • sm = small screens (tablets)
  • md = medium screens (some desktops)
  • lg = large screens (remaining desktops)

Read the "Grid Options" chapter from the official Bootstrap documentation for more details.

You should usually classify a div using multiple column classes so it behaves differently depending on the screen size (this is the heart of what makes bootstrap responsive). eg: a div with classes col-xs-6 and col-sm-4 will span half the screen on the mobile phone (xs) and 1/3 of the screen on tablets(sm).

<div class="col-xs-6 col-sm-4">Column 1</div> <!-- 1/2 width on mobile, 1/3 screen on tablet) -->
<div class="col-xs-6 col-sm-8">Column 2</div> <!-- 1/2 width on mobile, 2/3 width on tablet -->

NOTE: as per comment below, grid classes for a given screen size apply to that screen size and larger unless another declaration overrides it (i.e. col-xs-6 col-md-4 spans 6 columns on xs and sm, and 4 columns on md and lg, even though sm and lg were never explicitly declared)

NOTE: if you don't define xs, it will default to col-xs-12 (i.e. col-sm-6 is half the width on sm, md and lg screens, but full-width on xs screens).

NOTE: it's actually totally fine if your .row includes more than 12 cols, as long as you are aware of how they will react. --This is a contentious issue, and not everyone agrees.

How do I handle a click anywhere in the page, even when a certain element stops the propagation?

this is the key (vs evt.target). See example.

_x000D_
_x000D_
document.body.addEventListener("click", function (evt) {_x000D_
    console.dir(this);_x000D_
    //note evt.target can be a nested element, not the body element, resulting in misfires_x000D_
    console.log(evt.target);_x000D_
    alert("body clicked");_x000D_
});
_x000D_
<h4>This is a heading.</h4>_x000D_
<p>this is a paragraph.</p>
_x000D_
_x000D_
_x000D_

How to compile and run C in sublime text 3?

The latest build of the sublime even allows the direct command instead of double quotes. Try the below code for the build system

{
    "cmd" : ["gcc $file_name -o ${file_base_name} && ./${file_base_name}"],
    "selector" : "source.c",
    "shell": true,
    "working_dir" : "$file_path",
}

What is the difference between a database and a data warehouse?

The simplest way to explain it would be to say that a data warehouse consists of more than just a database. A database is an collection of data organized in some way, but a data warehouse is organized specifically to "facilitate reporting and analysis". This however is not the entire story as data warehousing also contains "the means to retrieve and analyze data, to extract, transform and load data, and to manage the data dictionary are also considered essential components of a data warehousing system".

Data Warehouse

Installing a specific version of angular with angular cli

use the following command to install the specific version. say you want to install angular/cli version 1.6.8 then enter the following command :

sudo npm install -g @angular/[email protected]

this will install angular/cli version 1.6.8

Is there a way to check for both `null` and `undefined`?

UPDATE (Sept 4, 2020)

You can now use the ?? operator to validate null and undefined "values" and set a default value. For example:

const foo = null;
const bar = foo ?? 'exampleValue';
console.log(bar); // This will print 'exampleValue' due to the value condition of the foo constant, in this case, a null value

As a verbose way, if you want to compare null and undefined values ONLY, use the following example code for reference:

const incomingValue : string = undefined;
const somethingToCompare : string = incomingValue; // If the line above is not declared, TypeScript will return an excepion

if (somethingToCompare == (undefined || null)) {
  console.log(`Incoming value is: ${somethingToCompare}`);
}

If incomingValue is not declared, TypeScript should return an exception. If this is declared but not defined, the console.log() will return "Incoming value is: undefined". Note we are not using the strict equals operator.

The "correct" way (check the other answers for details), if the incomingValue is not a boolean type, just evaluate if its value is true, this will be evaluated according to the constant/variable type. A true string have to be defined explicitly as string using the = '' assignation. If not, it will be evaluated as false. Let's check this case using the same context:

const incomingValue : string = undefined;
const somethingToCompare0 : string = 'Trumpet';
const somethingToCompare1 : string = incomingValue;

if (somethingToCompare0) {
  console.log(`somethingToCompare0 is: ${somethingToCompare0}`); // Will return "somethingToCompare0 is: Trumpet"
}

// Now, we will evaluate the second constant
if (somethingToCompare1) {
  console.log(`somethingToCompare1 is: ${somethingToCompare1}`); // Launched if incomingValue is defined
} else {
  console.log(`somethingToCompare1 is: ${somethingToCompare1}`); // Launched if incomingValue is undefined. Will return "somethingToCompare1 is: undefined"
}

How to save a base64 image to user's disk using JavaScript?

This Works

function saveBase64AsFile(base64, fileName) {
    var link = document.createElement("a");
    document.body.appendChild(link);
    link.setAttribute("type", "hidden");
    link.href = "data:text/plain;base64," + base64;
    link.download = fileName;
    link.click();  
    document.body.removeChild(link);
}

Based on the answer above but with some changes

jQuery AJAX submit form

This is a simple reference:

// this is the id of the form
$("#idForm").submit(function(e) {

    e.preventDefault(); // avoid to execute the actual submit of the form.

    var form = $(this);
    var url = form.attr('action');
    
    $.ajax({
           type: "POST",
           url: url,
           data: form.serialize(), // serializes the form's elements.
           success: function(data)
           {
               alert(data); // show response from the php script.
           }
         });

    
});

Git diff says subproject is dirty

To ignore all untracked files in any submodule use the following command to ignore those changes.

git config --global diff.ignoreSubmodules dirty

It will add the following configuration option to your local git config:

[diff]
  ignoreSubmodules = dirty

Further information can be found here

Getting multiple values with scanf()

Just to add, we can use array as well:

int i, array[4];
printf("Enter Four Ints: ");
for(i=0; i<4; i++) {
    scanf("%d", &array[i]);
}

What are the differences between LDAP and Active Directory?

https://jumpcloud.com/blog/difference-between-ldap-and-active-directory/

Realistically, there are probably more differences than similarities between the two directory solutions. Microsoft’s AD is largely a directory for Windows users, devices, and applications. AD requires a Microsoft Domain Controller to be present and when it is, users are able to single sign-on to Windows resources that live within the domain structure.

LDAP, on the other hand, has largely worked outside of the Windows structure focusing on the Linux / Unix environment and with more technical applications. LDAP doesn’t have the same concepts of domains or single sign-on. LDAP is largely implemented with open source solutions and as a result has more flexibility than AD.

Another critical difference between LDAP and Active Directory is how AD and LDAP each approach device management. AD manages Windows devices through and Group Policy Objects (GPOs). A similar concept doesn’t exist within LDAP. Both LDAP and AD are highly different solutions and as a result many organization must leverage both to serve different purposes.

This is why there’s an obvious opportunity for innovation. Why leverage and manage two complete systems, when one system can effectively merge the two?

Maven: Failed to retrieve plugin descriptor error

I had to change my password to the latest in the user.home/.m2/settings.xml file!

How do I enable MSDTC on SQL Server?

Can also see here on how to turn on MSDTC from the Control Panel's services.msc.

On the server where the trigger resides, you need to turn the MSDTC service on. You can this by clicking START > SETTINGS > CONTROL PANEL > ADMINISTRATIVE TOOLS > SERVICES. Find the service called 'Distributed Transaction Coordinator' and RIGHT CLICK (on it and select) > Start.

What does value & 0xff do in Java?

In 32 bit format system the hexadecimal value 0xff represents 00000000000000000000000011111111 that is 255(15*16^1+15*16^0) in decimal. and the bitwise & operator masks the same 8 right most bits as in first operand.

How to rename a file using svn?

You can do it by following 3 steps:

 - svn rm old_file_name
 - svn add new_file_name
 - svn commit

What does $_ mean in PowerShell?

$_ is an alias for automatic variable $PSItem (introduced in PowerShell V3.0; Usage information found here) which represents the current item from the pipe.

PowerShell (v6.0) online documentation for automatic variables is here.

Get name of current class?

Within the body of a class, the class name isn't defined yet, so it is not available. Can you not simply type the name of the class? Maybe you need to say more about the problem so we can find a solution for you.

I would create a metaclass to do this work for you. It's invoked at class creation time (conceptually at the very end of the class: block), and can manipulate the class being created. I haven't tested this:

class InputAssigningMetaclass(type):
    def __new__(cls, name, bases, attrs):
        cls.input = get_input(name)
        return super(MyType, cls).__new__(cls, name, bases, newattrs)

class MyBaseFoo(object):
    __metaclass__ = InputAssigningMetaclass

class foo(MyBaseFoo):
    # etc, no need to create 'input'

class foo2(MyBaseFoo):
    # etc, no need to create 'input'

Changing the git user inside Visual Studio Code

Generally VSCode uses the github credentials from system's credential manager, it doesn't store anywhere in the settings. As question says Changing the git user inside Visual Studio Code, is not inside rather outside.

Search for or Go to credential manager (Windows control panel) -> Windows Credentials -> Update the GitHub password from the list.

Detect changes in the DOM

MutationObserver = window.MutationObserver || window.WebKitMutationObserver;

var observer = new MutationObserver(function(mutations, observer) {
    // fired when a mutation occurs
    console.log(mutations, observer);
    // ...
});

// define what element should be observed by the observer
// and what types of mutations trigger the callback
observer.observe(document, {
  subtree: true,
  attributes: true
  //...
});

Complete explanations: https://stackoverflow.com/a/11546242/6569224

How to change a nullable column to not nullable in a Rails migration?

In Rails 4.02+ according to the docs there is no method like update_all with 2 arguments. Instead one can use this code:

# Make sure no null value exist
MyModel.where(date_column: nil).update_all(date_column: Time.now)

# Change the column to not allow null
change_column :my_models, :date_column, :datetime, null: false

.htaccess redirect www to non-www with SSL/HTTPS

Certificate must cover both www and non-www https. Some provider's certs cover both for www.xxxx.yyy, but only one for xxxx.yyy.

Turn on rewrites:

RewriteEngine On

Make all http use https:

RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://xxx.yyy/$1 [L,R=301]

Make only www https use the non-www https:

RewriteCond %{SERVER_PORT} 443
RewriteCond %{HTTP_HOST} ^www[.].+$
RewriteRule ^(.*)$ https://xxxx.yyy/$1 [L,R=301]

Cannot be processing non-www https, otherwise a loop occurs.

In [L,R=301]:

  1. L = If the rule was processed, don't process any more.
  2. R=301 = Tells browser/robot to do a permanent redirect.

More generic

A more generic approach -- not port-dependant -- is:

RewriteCond %{HTTP_HOST} ^www\.
RewriteRule ^(.*)$ https://xxxx.yyy/$1 [R=301,QSA]

to make any url with www drop it.

RewriteCond %{HTTPS} !on
RewriteCond %{HTTPS} !1
RewriteCond %{HTTP:X-Forwarded-Proto} !https
RewriteCond %{HTTP:X-Forwarded-SSL} !on
RewriteRule ^(.*)$ https://xxxx.yyy/$1 [R=301,QSA]

to force any non-https url, even for those system downstream from load-balancers that drop https, use https.

Note that I have not tested the forwarded options, so would appreciate feedback on any issues with them. Those lines could be left out if your system is not behind a load-balancer.

TO HTTP_HOST or not

You can use ${HTTP_HOST} to be part of the URL in the RewriteRule, or you can use your explicit canonical domain name text (xxxx.yyy above).

Specifying the domain name explicitly ensures that no slight-of-hand character-bending means are used in the user-supplied URL to possibly trick your site into doing something it might not be prepared for, or at least ensures that the proper domain name appears in the address bar, regardless of which URL string opened the page.

It might even help convert punycode-encoded domains to show the proper unicode characters in the address bar.

Hide axis and gridlines Highcharts

This has always worked well for me:

yAxes: [{
         ticks: {
                 display: false;
                },

Google Map API - Removing Markers

Following code might be useful if someone is using React and has a different component of Marker and want to remove marker from map.

export default function useGoogleMapMarker(props) {
  const [marker, setMarker] = useState();

  useEffect(() => {
    // ...code
    const marker = new maps.Marker({ position, map, title, icon });
    // ...code
    setMarker(marker);
    return () => marker.setMap(null); // to remove markers when unmounts
  }, []);

  return marker;
}

Can't update: no tracked branch

 git commit -m "first commit"

 git remote add origin <linkyourrepository>

 git push -u origin master

will works!

Share data between AngularJS controllers

A simple solution is to have your factory return an object and let your controllers work with a reference to the same object:

JS:

// declare the app with no dependencies
var myApp = angular.module('myApp', []);

// Create the factory that share the Fact
myApp.factory('Fact', function(){
  return { Field: '' };
});

// Two controllers sharing an object that has a string in it
myApp.controller('FirstCtrl', function( $scope, Fact ){
  $scope.Alpha = Fact;
});

myApp.controller('SecondCtrl', function( $scope, Fact ){
  $scope.Beta = Fact;
});

HTML:

<div ng-controller="FirstCtrl">
    <input type="text" ng-model="Alpha.Field">
    First {{Alpha.Field}}
</div>

<div ng-controller="SecondCtrl">
<input type="text" ng-model="Beta.Field">
    Second {{Beta.Field}}
</div>

Demo: http://jsfiddle.net/HEdJF/

When applications get larger, more complex and harder to test you might not want to expose the entire object from the factory this way, but instead give limited access for example via getters and setters:

myApp.factory('Data', function () {

    var data = {
        FirstName: ''
    };

    return {
        getFirstName: function () {
            return data.FirstName;
        },
        setFirstName: function (firstName) {
            data.FirstName = firstName;
        }
    };
});

With this approach it is up to the consuming controllers to update the factory with new values, and to watch for changes to get them:

myApp.controller('FirstCtrl', function ($scope, Data) {

    $scope.firstName = '';

    $scope.$watch('firstName', function (newValue, oldValue) {
        if (newValue !== oldValue) Data.setFirstName(newValue);
    });
});

myApp.controller('SecondCtrl', function ($scope, Data) {

    $scope.$watch(function () { return Data.getFirstName(); }, function (newValue, oldValue) {
        if (newValue !== oldValue) $scope.firstName = newValue;
    });
});

HTML:

<div ng-controller="FirstCtrl">
  <input type="text" ng-model="firstName">
  <br>Input is : <strong>{{firstName}}</strong>
</div>
<hr>
<div ng-controller="SecondCtrl">
  Input should also be here: {{firstName}}
</div>

Demo: http://jsfiddle.net/27mk1n1o/

Oracle "SQL Error: Missing IN or OUT parameter at index:: 1"

I got the same error and found the cause to be a wrong or missing foreign key. (Using JDBC)

How to give a pandas/matplotlib bar graph custom colors

For a more detailed answer on creating your own colormaps, I highly suggest visiting this page

If that answer is too much work, you can quickly make your own list of colors and pass them to the color parameter. All the colormaps are in the cm matplotlib module. Let's get a list of 30 RGB (plus alpha) color values from the reversed inferno colormap. To do so, first get the colormap and then pass it a sequence of values between 0 and 1. Here, we use np.linspace to create 30 equally-spaced values between .4 and .8 that represent that portion of the colormap.

from matplotlib import cm
color = cm.inferno_r(np.linspace(.4, .8, 30))
color

array([[ 0.865006,  0.316822,  0.226055,  1.      ],
       [ 0.851384,  0.30226 ,  0.239636,  1.      ],
       [ 0.832299,  0.283913,  0.257383,  1.      ],
       [ 0.817341,  0.270954,  0.27039 ,  1.      ],
       [ 0.796607,  0.254728,  0.287264,  1.      ],
       [ 0.775059,  0.239667,  0.303526,  1.      ],
       [ 0.758422,  0.229097,  0.315266,  1.      ],
       [ 0.735683,  0.215906,  0.330245,  1.      ],
       .....

Then we can use this to plot, using the data from the original post:

import random
x = [{i: random.randint(1, 5)} for i in range(30)]
df = pd.DataFrame(x)
df.plot(kind='bar', stacked=True, color=color, legend=False, figsize=(12, 4))

enter image description here

How do I get JSON data from RESTful service using Python?

I would give the requests library a try for this. Essentially just a much easier to use wrapper around the standard library modules (i.e. urllib2, httplib2, etc.) you would use for the same thing. For example, to fetch json data from a url that requires basic authentication would look like this:

import requests

response = requests.get('http://thedataishere.com',
                         auth=('user', 'password'))
data = response.json()

For kerberos authentication the requests project has the reqests-kerberos library which provides a kerberos authentication class that you can use with requests:

import requests
from requests_kerberos import HTTPKerberosAuth

response = requests.get('http://thedataishere.com',
                         auth=HTTPKerberosAuth())
data = response.json()

Automatically open default email client and pre-populate content

Implemented this way without using Jquery:

<button class="emailReplyButton" onClick="sendEmail(message)">Reply</button>

sendEmail(message) {
    var email = message.emailId;
    var subject = message.subject;
    var emailBody = 'Hi '+message.from;
    document.location = "mailto:"+email+"?subject="+subject+"&body="+emailBody;
}

Angular 2 Sibling Component Communication

In case of 2 different components (not nested components, parent\child\grandchild ) I suggest you this:

MissionService:

import { Injectable } from '@angular/core';
import { Subject }    from 'rxjs/Subject';

@Injectable()

export class MissionService {
  // Observable string sources
  private missionAnnouncedSource = new Subject<string>();
  private missionConfirmedSource = new Subject<string>();
  // Observable string streams
  missionAnnounced$ = this.missionAnnouncedSource.asObservable();
  missionConfirmed$ = this.missionConfirmedSource.asObservable();
  // Service message commands
  announceMission(mission: string) {
    this.missionAnnouncedSource.next(mission);
  }
  confirmMission(astronaut: string) {
    this.missionConfirmedSource.next(astronaut);
  }

}

AstronautComponent:

import { Component, Input, OnDestroy } from '@angular/core';
import { MissionService } from './mission.service';
import { Subscription }   from 'rxjs/Subscription';
@Component({
  selector: 'my-astronaut',
  template: `
    <p>
      {{astronaut}}: <strong>{{mission}}</strong>
      <button
        (click)="confirm()"
        [disabled]="!announced || confirmed">
        Confirm
      </button>
    </p>
  `
})
export class AstronautComponent implements OnDestroy {
  @Input() astronaut: string;
  mission = '<no mission announced>';
  confirmed = false;
  announced = false;
  subscription: Subscription;
  constructor(private missionService: MissionService) {
    this.subscription = missionService.missionAnnounced$.subscribe(
      mission => {
        this.mission = mission;
        this.announced = true;
        this.confirmed = false;
    });
  }
  confirm() {
    this.confirmed = true;
    this.missionService.confirmMission(this.astronaut);
  }
  ngOnDestroy() {
    // prevent memory leak when component destroyed
    this.subscription.unsubscribe();
  }
}

Source: Parent and children communicate via a service

Adding null values to arraylist

You can add nulls to the ArrayList, and you will have to check for nulls in the loop:

for(Item i : itemList) {
   if (i != null) {

   }
}

itemsList.size(); would take the null into account.

 List<Integer> list = new ArrayList<Integer>();
 list.add(null);
 list.add (5);
 System.out.println (list.size());
 for (Integer value : list) {
   if (value == null)
       System.out.println ("null value");
   else 
       System.out.println (value);
 }

Output :

2
null value
5

Remove spacing between table cells and rows

If you see table class it has border-spacing: 2px; You could override table class in your css and set its border-spacing: 0px!important in table; I did it like

table {
      border-collapse: separate;
      white-space: normal;
      line-height: normal;
      font-weight: normal;
      font-size: medium;
      font-style: normal;
      color: -internal-quirk-inherit;
      text-align: start;
      border-spacing: 0px!important;
      font-variant: normal;   }

It saved my day.Hope it would be of help. Thanks.

How do I get the project basepath in CodeIgniter

Change your default controller which is in config file.

i.e : config/routes.php

$route['default_controller'] = "Your controller name";

Hope this will help.

best way to get folder and file list in Javascript

In my project I use this function for getting huge amount of files. It's pretty fast (put require("FS") out to make it even faster):

var _getAllFilesFromFolder = function(dir) {

    var filesystem = require("fs");
    var results = [];

    filesystem.readdirSync(dir).forEach(function(file) {

        file = dir+'/'+file;
        var stat = filesystem.statSync(file);

        if (stat && stat.isDirectory()) {
            results = results.concat(_getAllFilesFromFolder(file))
        } else results.push(file);

    });

    return results;

};

usage is clear:

_getAllFilesFromFolder(__dirname + "folder");

Bootstrap: Open Another Modal in Modal

I also had some trouble with my scrollable modals, so I did something like this:

  $('.modal').on('shown.bs.modal', function () {
    $('body').addClass('modal-open');
    // BS adds some padding-right to acomodate the scrollbar at right
    $('body').removeAttr('style');
  })

  $(".modal [data-toggle='modal']").click(function(){
    $(this).closest(".modal").modal('hide');
  });

It will serve for any modal whithin a modal that comes to appear. Note that the first its closed so the second can appear. No changes in the Bootstrap structure.

Simple mediaplayer play mp3 from file path?

It works like this:

mpintro = MediaPlayer.create(this, Uri.parse(Environment.getExternalStorageDirectory().getPath()+ "/Music/intro.mp3"));
mpintro.setLooping(true);
        mpintro.start();

It did not work properly as string filepath...

What version of MongoDB is installed on Ubuntu

ANSWER: Read the instructions #dua

Ok the magic was in this line that I apparently missed when installing was:

$ sudo apt-get install mongodb-10gen=2.4.6

And the full process as described here http://docs.mongodb.org/manual/tutorial/install-mongodb-on-ubuntu/ is

$ sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 7F0CEB10
$ echo 'deb http://downloads-distro.mongodb.org/repo/ubuntu-upstart dist 10gen' | sudo tee /etc/apt/sources.list.d/mongodb.list
$ sudo apt-get update
$ sudo apt-get install mongodb-10gen
$ sudo apt-get install mongodb-10gen=2.2.3
$ echo "mongodb-10gen hold" | sudo dpkg --set-selections
$ sudo service mongodb start

$ mongod --version
db version v2.4.6
Wed Oct 16 12:21:39.938 git version: b9925db5eac369d77a3a5f5d98a145eaaacd9673

IMPORTANT: Make sure you change 2.4.6 to the latest version (or whatever you want to install). Find the latest version number here http://www.mongodb.org/downloads

Gradle - Could not find or load main class

I resolved it by adding below code to my application.

// enter code here this is error I was getting when I run build.gradle. main class name has not been configured and it could not be resolved

public static void main(String[] args) {
    SpringApplication.run(Application.class, args);
}

How to use jQuery Plugin with Angular 4?

the solution to the typescript:

Step1:

npm install jquery

npm install --save-dev @types/jquery

step2: in Angular.json add:

"scripts": [
        "node_modules/jquery/dist/jquery.min.js",
      ]

or in index.html add:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>

step3: in *.component.ts where you want to use jquery

import * as $ from 'jquery';  // dont need "declare let $"

Then you can use jquery the same as javaScript. This way, VScode supports auto-suggestion by Typescript

Php, wait 5 seconds before executing an action

i use this

    $i = 1;
    $last_time = $_SERVER['REQUEST_TIME'];
    while($i > 0){
        $total = $_SERVER['REQUEST_TIME'] - $last_time;
        if($total >= 2){
            // Code Here
            $i = -1;
        }
    }

you can use

function WaitForSec($sec){
    $i = 1;
    $last_time = $_SERVER['REQUEST_TIME'];
    while($i > 0){
        $total = $_SERVER['REQUEST_TIME'] - $last_time;
        if($total >= 2){
            return 1;
            $i = -1;
        }
    }
}

and run code =>

WaitForSec(your_sec);

Example :

WaitForSec(5);

OR you can use sleep

Example :

sleep(5);

How to call getResources() from a class which has no context?

Example: Getting app_name string:

Resources.getSystem().getString( R.string.app_name )

How to run a C# application at Windows startup?

for WPF: (where lblInfo is a label, chkRun is a checkBox)

this.Topmost is just to keep my app on the top of other windows, you will also need to add a using statement " using Microsoft.Win32; ", StartupWithWindows is my application's name

public partial class MainWindow : Window
    {
        // The path to the key where Windows looks for startup applications
        RegistryKey rkApp = Registry.CurrentUser.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);

        public MainWindow()
        {
            InitializeComponent();
            if (this.IsFocused)
            {
                this.Topmost = true;
            }
            else
            {
                this.Topmost = false;
            }

            // Check to see the current state (running at startup or not)
            if (rkApp.GetValue("StartupWithWindows") == null)
            {
                // The value doesn't exist, the application is not set to run at startup, Check box
                chkRun.IsChecked = false;
                lblInfo.Content = "The application doesn't run at startup";
            }
            else
            {
                // The value exists, the application is set to run at startup
                chkRun.IsChecked = true;
                lblInfo.Content = "The application runs at startup";
            }
            //Run at startup
            //rkApp.SetValue("StartupWithWindows",System.Reflection.Assembly.GetExecutingAssembly().Location);

            // Remove the value from the registry so that the application doesn't start
            //rkApp.DeleteValue("StartupWithWindows", false);

        }

        private void btnConfirm_Click(object sender, RoutedEventArgs e)
        {
            if ((bool)chkRun.IsChecked)
            {
                // Add the value in the registry so that the application runs at startup
                rkApp.SetValue("StartupWithWindows", System.Reflection.Assembly.GetExecutingAssembly().Location);
                lblInfo.Content = "The application will run at startup";
            }
            else
            {
                // Remove the value from the registry so that the application doesn't start
                rkApp.DeleteValue("StartupWithWindows", false);
                lblInfo.Content = "The application will not run at startup";
            }
        }

    }

Get the current first responder without using a private API

Here is a Extension implemented in Swift based on Jakob Egger's most excellent answer:

import UIKit

extension UIResponder {
    // Swift 1.2 finally supports static vars!. If you use 1.1 see: 
    // http://stackoverflow.com/a/24924535/385979
    private weak static var _currentFirstResponder: UIResponder? = nil
    
    public class func currentFirstResponder() -> UIResponder? {
        UIResponder._currentFirstResponder = nil
        UIApplication.sharedApplication().sendAction("findFirstResponder:", to: nil, from: nil, forEvent: nil)
        return UIResponder._currentFirstResponder
    }
    
    internal func findFirstResponder(sender: AnyObject) {
        UIResponder._currentFirstResponder = self
    }
}

Swift 4

import UIKit    

extension UIResponder {
    private weak static var _currentFirstResponder: UIResponder? = nil
    
    public static var current: UIResponder? {
        UIResponder._currentFirstResponder = nil
        UIApplication.shared.sendAction(#selector(findFirstResponder(sender:)), to: nil, from: nil, for: nil)
        return UIResponder._currentFirstResponder
    }
    
    @objc internal func findFirstResponder(sender: AnyObject) {
        UIResponder._currentFirstResponder = self
    }
}

Changing file permission in Python

You can use, pathlib also

from pathlib import Path

fl = Path("file_name")

fl.chmod(0o444)

OpenSSL: unable to verify the first certificate for Experian URL

If you are using MacOS use:

sudo cp /usr/local/etc/openssl/cert.pem /etc/ssl/certs

after this Trust anchor not found error disappears

What is the best way to search the Long datatype within an Oracle database?

Example:

create table longtable(id number,text long);

insert into longtable values(1,'hello world');
insert into longtable values(2,'say hello!');

commit;

create or replace function search_long(r rowid) return varchar2 is
temporary_varchar varchar2(4000);
begin
select text into temporary_varchar from longtable where rowid=r;
return temporary_varchar;
end;
/


SQL> select text from longtable where search_long(rowid) like '%hello%';                                                                              

TEXT
--------------------------------------------------------------------------------
hello world
say hello!

But be careful. A PL/SQL function will only search the first 32K of LONG.

How can I make an EXE file from a Python program?

py2exe:

py2exe is a Python Distutils extension which converts Python scripts into executable Windows programs, able to run without requiring a Python installation.

Check if inputs form are empty jQuery

var empty = true;
$('input[type="text"]').each(function() {
   if ($(this).val() != "") {
      empty = false;
      return false;
   }
});

This should look all the input and set the empty var to false, if at least one is not empty.

EDIT:

To match the OP edit request, this can be used to filter input based on name substring.

$('input[name*="denominationcomune_"]').each(...

NodeJS w/Express Error: Cannot GET /

You need to add a return to the index.html file.

app.use(express.static(path.join(__dirname, 'build')));

app.get('*', function(req, res) {res.sendFile(path.join(__dirname + '/build/index.html')); });

Create a asmx web service in C# using visual studio 2013

Short answer: Don't do it.

Longer answer: Use WCF. It's here to replace Asmx.

see this answer for example, or the first comment on this one.

John Saunders: ASMX is a legacy technology, and should not be used for new development. WCF or ASP.NET Web API should be used for all new development of web service clients and servers. One hint: Microsoft has retired the ASMX Forum on MSDN.


As for comment ... well, if you have to, you have to. I'll leave you in the competent hands of the other answers then. (Even though it's funny it has issues, and if it does, why are you doing it in VS2013 to begin with ?)

Mysql command not found in OS X 10.7

It is possible you are using zsh instead of bash then you have to enter the above mentioned commands in .zshenv instead of .bash_profile

Insert NULL value into INT column

Does the column allow null?

Seems to work. Just tested with phpMyAdmin, the column is of type int that allows nulls:

INSERT INTO `database`.`table` (`column`) VALUES (NULL);

Drawing in Java using Canvas

Why would the first way not work. Canvas object is created and the size is set and the grahpics are set. I always find this strange. Also if a class extends JComponent you can override the

paintComponent(){
  super...
}

and then shouldn't you be able to create and instance of the class inside of another class and then just call NewlycreateinstanceOfAnyClass.repaint();

I have tried this approach for some game programming I have been working and it doesn't seem to work the way I think that it should be.

Doug Hauf

Root element is missing

  1. Check the trees.config file which located in config folder... sometimes (I don't know why) this file became to be empty like someone delete the content inside... keep backup up of this file in your local pc then when this error appear - replace the server file with your local file. This is what i do when this error happened.

  2. check the available space on the server. sometimes this is the problem.

Good luck.

Angular ng-click with call to a controller function not working

You should probably use the ngHref directive along with the ngClick:

 <a ng-href='#here' ng-click='go()' >click me</a>

Here is an example: http://plnkr.co/edit/FSH0tP0YBFeGwjIhKBSx?p=preview

<body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>
    {{msg}}
    <a ng-href='#here' ng-click='go()' >click me</a>
    <div style='height:1000px'>

      <a id='here'></a>

    </div>
     <h1>here</h1>
  </body>

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

app.controller('MainCtrl', function($scope) {
  $scope.name = 'World';

  $scope.go = function() {

    $scope.msg = 'clicked';
  }
});

I don't know if this will work with the library you are using but it will at least let you link and use the ngClick function.

** Update **

Here is a demo of the set and get working fine with a service.

http://plnkr.co/edit/FSH0tP0YBFeGwjIhKBSx?p=preview

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

app.controller('MainCtrl', function($scope, sharedProperties) {
  $scope.name = 'World';

  $scope.go = function(item) {
    sharedProperties.setListName(item);


  }

  $scope.getItem = function() {

    $scope.msg = sharedProperties.getListName();
  }
});

app.service('sharedProperties', function () {
    var list_name = '';

    return {

        getListName: function() {
            return list_name;
        },
        setListName: function(name) {
            list_name = name;
        }
    };


});

* Edit *

Please review https://github.com/centralway/lungo-angular-bridge which talks about how to use lungo and angular. Also note that if your page is completely reloading when browsing to another link, you will need to persist your shared properties into localstorage and/or a cookie.

jQuery function to get all unique elements from an array?

Just use this code as the basis of a simple JQuery plugin.

$.extend({
    distinct : function(anArray) {
       var result = [];
       $.each(anArray, function(i,v){
           if ($.inArray(v, result) == -1) result.push(v);
       });
       return result;
    }
});

Use as so:

$.distinct([0,1,2,2,3]);

How to get tf.exe (TFS command line client)?

The tf.exe command line is included in the VSTS agent package in folder externals\vstsom.

How to change the button color when it is active using bootstrap?

CSS has different pseudo selector by which you can achieve such effect. In your case you can use

:active : if you want background color only when the button is clicked and don't want to persist.

:focus: if you want background color untill the focus is on the button.

button:active{
    background:olive;
}

and

button:focus{
    background:olive;
}

JsFiddle Example

P.S.: Please don't give the number in Id attribute of html elements.

python - if not in list

Your code should work, but you can also try:

    if not item in mylist :

SQL WHERE condition is not equal to?

Best solution is to use

DELETE FROM table WHERE id NOT IN ( 2 )

How to show an empty view with a RecyclerView?

RVEmptyObserver

Instead of using a custom RecyclerView, extending an AdapterDataObserver is a simpler solution that allows setting a custom View that is displayed when there are no items in the list:

Example Usage:

RVEmptyObserver observer = new RVEmptyObserver(recyclerView, emptyView)
rvAdapter.registerAdapterDataObserver(observer);

Class:

public class RVEmptyObserver extends RecyclerView.AdapterDataObserver {
    private View emptyView;
    private RecyclerView recyclerView;

    public RVEmptyObserver(RecyclerView rv, View ev) {
        this.recyclerView = rv;
        this.emptyView    = ev;
        checkIfEmpty();
    }

    private void checkIfEmpty() {
        if (emptyView != null && recyclerView.getAdapter() != null) {
            boolean emptyViewVisible = recyclerView.getAdapter().getItemCount() == 0;
            emptyView.setVisibility(emptyViewVisible ? View.VISIBLE : View.GONE);
            recyclerView.setVisibility(emptyViewVisible ? View.GONE : View.VISIBLE);
        }
    }

    public void onChanged() { checkIfEmpty(); }
    public void onItemRangeInserted(int positionStart, int itemCount) { checkIfEmpty(); }
    public void onItemRangeRemoved(int positionStart, int itemCount) { checkIfEmpty(); }
}

How to call Makefile from another Makefile?

http://www.gnu.org/software/make/manual/make.html#Recursion

 subsystem:
         cd subdir && $(MAKE)

or, equivalently, this :

 subsystem:
         $(MAKE) -C subdir

How do I call a Django function on button click?

The following answer could be helpful for the first part of your question:

Django: How can I call a view function from template?

How to Bootstrap navbar static to fixed on scroll?

Use the affix component included with Bootstrap. Start with a 'navbar-static-top' and this will change it to fixed when the height of your header (content above the navbar) is reached...

$('#nav').affix({
      offset: {
        top: $('header').height()
      }
}); 

http://bootply.com/107973

Adding to an ArrayList Java

Instantiate a new ArrayList:

List<String> myList = new ArrayList<String>();

Iterate over your data structure (with a for loop, for instance, more details on your code would help.) and for each element (yourElement):

myList.add(yourElement);

When to use 'raise NotImplementedError'?

Consider if instead it was:

class RectangularRoom(object):
    def __init__(self, width, height):
        pass

    def cleanTileAtPosition(self, pos):
        pass

    def isTileCleaned(self, m, n):
        pass

and you subclass and forget to tell it how to isTileCleaned() or, perhaps more likely, typo it as isTileCLeaned(). Then in your code, you'll get a None when you call it.

  • Will you get the overridden function you wanted? Definitely not.
  • Is None valid output? Who knows.
  • Is that intended behavior? Almost certainly not.
  • Will you get an error? It depends.

raise NotImplmentedError forces you to implement it, as it will throw an exception when you try to run it until you do so. This removes a lot of silent errors. It's similar to why a bare except is almost never a good idea: because people make mistakes and this makes sure they aren't swept under the rug.

Note: Using an abstract base class, as other answers have mentioned, is better still, as then the errors are frontloaded and the program won't run until you implement them (with NotImplementedError, it will only throw an exception if actually called).

Get Row Index on Asp.net Rowcommand event

If you have a built-in command of GridView like insert, update or delete, on row command you can use the following code to get the index:

int index = Convert.ToInt32(e.CommandArgument);

In a custom command, you can set the command argument to yourRow.RowIndex.ToString() and then get it back in the RowCommand event handler. Unless, of course, you need the command argument for another purpose.

Define css class in django Forms

Here is another solution for adding class definitions to the widgets after declaring the fields in the class.

def __init__(self, *args, **kwargs):
    super(SampleClass, self).__init__(*args, **kwargs)
    self.fields['name'].widget.attrs['class'] = 'my_class'

Replace a value if null or undefined in JavaScript

?? should be preferred to || because it checks only for nulls and undefined.

All The expressions below are true:

(null || 'x') === 'x' ;
(undefined || 'x') === 'x' ;
//Most of the times you don't want the result below
('' || 'x') === 'x'  ;
(0 || 'x') === 'x' ;
(false || 'x') === 'x' ;
//-----

//Using ?? is preferred
(null ?? 'x') === 'x' ;
(undefined ?? 'x') === 'x' ;
//?? works only for null and undefined, which is in general safer
('' ?? 'x') === '' ;
(0 ?? 'x') === 0 ;
(false ?? 'x') === false ;

Bottom line:

int j=i ?? 10; is perfectly fine to use in javascript also. Just replace int with let.

Asterisk: Check browser compatibility and if you really need to support these other browsers use babel.

"inconsistent use of tabs and spaces in indentation"

Use pylint it will give you a detailed report about how many spaces you need and where.

Tests not running in Test Explorer

You can view the error-output of your test runner by opening the Output panel (view-->output) and choosing "tests" from the "Show output from" dropdown

show output from


Additionally, if you have Resharper installed you can open a test file and hover over the test-circle next to a test to get additional error info

Resharper output

Clicking that will bring you to a window with more detailed information. Alternatively, you can open that window by going to Extensions --> Reshaper --> Windows --> Unit Test Exploration Results

Resharper Unit Test Exploration

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

Java: Static Class?

Sounds like you have a utility class similar to java.lang.Math.
The approach there is final class with private constructor and static methods.

But beware of what this does for testability, I recommend reading this article
Static Methods are Death to Testability

Check whether a table contains rows or not sql server 2005

For what purpose?

  • Quickest for an IF would be IF EXISTS (SELECT * FROM Table)...
  • For a result set, SELECT TOP 1 1 FROM Table returns either zero or one rows
  • For exactly one row with a count (0 or non-zero), SELECT COUNT(*) FROM Table

Difference between window.location.href=window.location.href and window.location.reload()

If you add the boolean true to the reload window.location.reload(true) it will load from server.

It is not clear how supported this boolean is, W3Org mentions that NS used to support it

There MIGHT be a difference between the content of window.location.href and document.URL - there at least used to be a difference between location.href and the non-standard and deprecated document.location that had to do with redirection, but that is really last millennium.

For documentation purposes I would use window.location.reload() because that is what you want to do.

Why is visible="false" not working for a plain html table?

visibility:hidden is the proper syntax, but another way to 'hide' the table is with display:none or dynamically with JQuery:

$('#myTable').hide()

Gray out image with CSS?

Here's an example that let's you set the color of the background. If you don't want to use float, then you might need to set the width and height manually. But even that really depends on the surrounding CSS/HTML.

<style>
#color {
  background-color: red;
  float: left;
}#opacity    {
    opacity : 0.4;
    filter: alpha(opacity=40); 
}
</style>

<div id="color">
  <div id="opacity">
    <img src="image.jpg" />
  </div>
</div>

Android - How to regenerate R class?

For me, it was a String value Resource not being defined … after I added it by hand to Strings.xml, the R class was automagically regenerated!

Why is Node.js single threaded?

Node.js was created explicitly as an experiment in async processing. The theory was that doing async processing on a single thread could provide more performance and scalability under typical web loads than the typical thread-based implementation.

And you know what? In my opinion that theory's been borne out. A node.js app that isn't doing CPU intensive stuff can run thousands more concurrent connections than Apache or IIS or other thread-based servers.

The single threaded, async nature does make things complicated. But do you honestly think it's more complicated than threading? One race condition can ruin your entire month! Or empty out your thread pool due to some setting somewhere and watch your response time slow to a crawl! Not to mention deadlocks, priority inversions, and all the other gyrations that go with multithreading.

In the end, I don't think it's universally better or worse; it's different, and sometimes it's better and sometimes it's not. Use the right tool for the job.

When using Trusted_Connection=true and SQL Server authentication, will this affect performance?

This will probably have some performance costs when creating the connection but as connections are pooled, they are created only once and then reused, so it won't make any difference to your application. But as always: measure it.


UPDATE:

There are two authentication modes:

  1. Windows Authentication mode (corresponding to a trusted connection). Clients need to be members of a domain.
  2. SQL Server Authentication mode. Clients are sending username/password at each connection

Can I give a default value to parameters or optional parameters in C# functions?

This is a feature of C# 4.0, but was not possible without using function overload prior to that version.

How to reload or re-render the entire page using AngularJS

$route.reload() will reinitialise the controllers but not the services. If you want to reset the whole state of your application you can use:

$window.location.reload();

This is a standard DOM method which you can access injecting the $window service.

If you want to be sure to reload the page from the server, for example when you are using Django or another web framework and you want a fresh server side render, pass true as a parameter to reload, as explained in the docs. Since that requires interaction with the server, it will be slower so do it only if necessary

Angular 2

The above applies to Angular 1. I am not using Angular 2, looks like the services are different there, there is Router, Location, and the DOCUMENT. I did not test different behaviors there

No value accessor for form control with name: 'recipient'

Make sure you import MaterialModule as well since you are using md-input which does not belong to FormsModule

Procedure or function !!! has too many arguments specified

Yet another cause of this error is when you are calling the stored procedure from code, and the parameter type in code does not match the type on the stored procedure.

Bootstrap Datepicker - Months and Years Only

I'm using version 2(supports both bootstrap v2 and v3) and for me this works:

$("#datepicker").datepicker( {
    format: "mm/yyyy",
    startView: "year", 
    minView: "year"
});

Go Back to Previous Page

Depends what it is that you're trying to do it with. You could use something like this:

echo "<a href=\"javascript:history.go(-1)\">GO BACK</a>";

That's the simplest option. The other poster is right about having a proper flow of history but this is an example for you.

Just edited, orig version wasn't indented and looked like nothing. ;)

jQuery: Currency Format Number

_x000D_
_x000D_
var input=950000; _x000D_
var output=parseInt(input).toLocaleString(); _x000D_
alert(output);
_x000D_
_x000D_
_x000D_

Is this how you define a function in jQuery?

No, you can just write the function as:

$(document).ready(function() {
    MyBlah("hello");
});

function MyBlah(blah) {
    alert(blah);
}

This calls the function MyBlah on content ready.

How do I properly set the Datetimeindex for a Pandas datetime object in a dataframe?

You are not creating datetime index properly,

format = '%Y-%m-%d %H:%M:%S'
df['Datetime'] = pd.to_datetime(df['date'] + ' ' + df['time'], format=format)
df = df.set_index(pd.DatetimeIndex(df['Datetime']))

How to get a unique computer identifier in Java (like disk ID or motherboard ID)?

The OSHI project provides platform-independent hardware utilities.

Maven dependency:

<dependency>
    <groupId>com.github.oshi</groupId>
    <artifactId>oshi-core</artifactId>
    <version>LATEST</version>
</dependency>

For instance, you could use something like the following code to identify a machine uniquely:

import oshi.SystemInfo;
import oshi.hardware.CentralProcessor;
import oshi.hardware.ComputerSystem;
import oshi.hardware.HardwareAbstractionLayer;
import oshi.software.os.OperatingSystem;

class ComputerIdentifier
{
    static String generateLicenseKey()
    {
        SystemInfo systemInfo = new SystemInfo();
        OperatingSystem operatingSystem = systemInfo.getOperatingSystem();
        HardwareAbstractionLayer hardwareAbstractionLayer = systemInfo.getHardware();
        CentralProcessor centralProcessor = hardwareAbstractionLayer.getProcessor();
        ComputerSystem computerSystem = hardwareAbstractionLayer.getComputerSystem();

        String vendor = operatingSystem.getManufacturer();
        String processorSerialNumber = computerSystem.getSerialNumber();
        String processorIdentifier = centralProcessor.getIdentifier();
        int processors = centralProcessor.getLogicalProcessorCount();

        String delimiter = "#";

        return vendor +
                delimiter +
                processorSerialNumber +
                delimiter +
                processorIdentifier +
                delimiter +
                processors;
    }

    public static void main(String[] arguments)
    {
        String identifier = generateLicenseKey();
        System.out.println(identifier);
    }
}

Output for my machine:

Microsoft#57YRD12#Intel64 Family 6 Model 60 Stepping 3#8

Your output will be different since at least the processor serial number will differ.

Display array values in PHP

a simple code snippet that i prepared, hope it will be usefull for you;

$ages = array("Kerem"=>"35","Ahmet"=>"65","Talip"=>"62","Kamil"=>"60");

reset($ages);

for ($i=0; $i < count($ages); $i++){
echo "Key : " . key($ages) . " Value : " . current($ages) . "<br>";
next($ages);
}
reset($ages);

Convert hex string to int in Python

Without the 0x prefix, you need to specify the base explicitly, otherwise there's no way to tell:

x = int("deadbeef", 16)

With the 0x prefix, Python can distinguish hex and decimal automatically.

>>> print(int("0xdeadbeef", 0))
3735928559
>>> print(int("10", 0))
10

(You must specify 0 as the base in order to invoke this prefix-guessing behavior; if you omit the second parameter int() will assume base-10.)

How can I start PostgreSQL server on Mac OS X?

This worked for me (macOS v10.13 (High Sierra)):

sudo -u postgres /Library/PostgreSQL/9.6/bin/pg_ctl start -D /Library/PostgreSQL/9.6/data

Or first

cd /Library/PostgreSQL/9.6/bin/

How do I find an array item with TypeScript? (a modern, easier way)

Part One - Polyfill

For browsers that haven't implemented it, a polyfill for array.find. Courtesy of MDN.

if (!Array.prototype.find) {
  Array.prototype.find = function(predicate) {
    if (this == null) {
      throw new TypeError('Array.prototype.find called on null or undefined');
    }
    if (typeof predicate !== 'function') {
      throw new TypeError('predicate must be a function');
    }
    var list = Object(this);
    var length = list.length >>> 0;
    var thisArg = arguments[1];
    var value;

    for (var i = 0; i < length; i++) {
      value = list[i];
      if (predicate.call(thisArg, value, i, list)) {
        return value;
      }
    }
    return undefined;
  };
}

Part Two - Interface

You need to extend the open Array interface to include the find method.

interface Array<T> {
    find(predicate: (search: T) => boolean) : T;
}

When this arrives in TypeScript, you'll get a warning from the compiler that will remind you to delete this.

Part Three - Use it

The variable x will have the expected type... { id: number }

var x = [{ "id": 1 }, { "id": -2 }, { "id": 3 }].find(myObj => myObj.id < 0);

What is the difference between rb and r+b modes in file objects

On Windows, 'b' appended to the mode opens the file in binary mode, so there are also modes like 'rb', 'wb', and 'r+b'. Python on Windows makes a distinction between text and binary files; the end-of-line characters in text files are automatically altered slightly when data is read or written. This behind-the-scenes modification to file data is fine for ASCII text files, but it’ll corrupt binary data like that in JPEG or EXE files. Be very careful to use binary mode when reading and writing such files. On Unix, it doesn’t hurt to append a 'b' to the mode, so you can use it platform-independently for all binary files.

Source: Reading and Writing Files

CSS full screen div with text in the middle

text-align: center will center it horizontally as for vertically put it in a span and give it a css of margin:auto 0; (you will probably also have to give the span a display: block property)

How do you uninstall all dependencies listed in package.json (NPM)?

If using Bash, just switch into the folder that has your package.json file and run the following:

for package in `ls node_modules`; do npm uninstall $package; done;

In the case of globally-installed packages, switch into your %appdata%/npm folder (if on Windows) and run the same command.

EDIT: This command breaks with npm 3.3.6 (Node 5.0). I'm now using the following Bash command, which I've mapped to npm_uninstall_all in my .bashrc file:

npm uninstall `ls -1 node_modules | tr '/\n' ' '`

Added bonus? it's way faster!

https://github.com/npm/npm/issues/10187

Why does NULL = NULL evaluate to false in SQL server

Just because you don't know what two things are, does not mean they're equal. If when you think of NULL you think of “NULL” (string) then you probably want a different test of equality like Postgresql's IS DISTINCT FROM AND IS NOT DISTINCT FROM

From the PostgreSQL docs on "Comparison Functions and Operators"

expression IS DISTINCT FROM expression

expression IS NOT DISTINCT FROM expression

For non-null inputs, IS DISTINCT FROM is the same as the <> operator. However, if both inputs are null it returns false, and if only one input is null it returns true. Similarly, IS NOT DISTINCT FROM is identical to = for non-null inputs, but it returns true when both inputs are null, and false when only one input is null. Thus, these constructs effectively act as though null were a normal data value, rather than "unknown".

Create a txt file using batch file in a specific folder

You have it almost done. Just explicitly say where to create the file

@echo off
  echo.>"d:\testing\dblank.txt"

This creates a file containing a blank line (CR + LF = 2 bytes).

If you want the file empty (0 bytes)

@echo off
  break>"d:\testing\dblank.txt"

How do I set a background-color for the width of text, not the width of the entire element, using CSS?

can use html5 mark tag within paragraph and heading tag.

_x000D_
_x000D_
<p>lorem ipsum <mark>Highlighted Text</mark> dolor sit.</p>
_x000D_
_x000D_
_x000D_

CSS: transition opacity on mouse-out?

I managed to find a solution using css/jQuery that I'm comfortable with. The original issue: I had to force the visibility to be shown while animating as I have elements hanging outside the area. Doing so, made large blocks of text now hang outside the content area during animation as well.

The solution was to start the main text elements with an opacity of 0 and use addClass to inject and transition to an opacity of 1. Then removeClass when clicked on again.

I'm sure there's an all jQquery way to do this. I'm just not the guy to do it. :)

So in it's most basic form...

.slideDown().addClass("load");
.slideUp().removeClass("load");

Thanks for the help everyone.

Can an html element have multiple ids?

No. While the definition from w3c for HTML 4 doesn't seem to explicitly cover your question, the definition of the name and id attribute says no spaces in the identifier:

ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").

get selected value in datePicker and format it

If you want to take the formatted value of input do this :

$("input").datepicker({ dateFormat: 'dd, mm, yy' });

later in your code when the date is set you could get it by

dateVariable = $("input").val();

If you want just to take a formatted value with datepicker you might want to use the utility

dateString = $.datepicker.formatDate('dd, MM, yy', new Date("20 April 2012"));

I've updated the jsfiddle for experimenting with this

Excel 2013 VBA Clear All Filters macro

Loop AutoFilter columns, if column is activated(on) then reset a column filter, you may insert a new criteria after a loop. This code does not remove AutoFilter banner.

Dim iCol as Long
Dim ws as Worksheet
...
For iCol = 1 To ws.AutoFilter.Filters.count
  If ws.AutoFilter.Filters(iCol).On Then ws.AutoFilter.Range.AutoFilter Field:=iCol
Next
...
ws.AutoFilter.Range.AutoFilter Field:=4, Criteria1:="AABBCC"

Do you have to include <link rel="icon" href="favicon.ico" type="image/x-icon" />?

You should in fact do both, so that all browsers will find the icon.

Naming the file "favicon.ico" and putting it in the root of your website is the method "discouraged" by W3C:

Method 2 (Discouraged): Putting the favicon at a predefined URI
A second method for specifying a favicon relies on using a predefined URI to identify the image: "/favicon", which is relative to the server root. This method works because some browsers have been programmed to look for favicons using that URI.
W3C - How to add a favicon to your site

So, to cover all situations, I always do that in addition to the recommended method of adding a "rel" attribute and pointing it to the same .ico file.

What are some great online database modeling tools?

S.Lott inserted a comment, but it should be an answer: see the same question.

EDIT

Since it wasn't as obvious as I intended it to be, here follows a verbatim copy of S.Lott's answer in the other question:

I'm a big fan of ARGO UML from Tigris.org. Draws nice pictures using standard UML notation. It does some code generation, but mostly Java classes, which isn't SQL DDL, so that may not be close enough to what you want to do.

You can look at the Data Modelling Tools list and see if anything there is better than Argo UML. Many of the items on this list are free or cheap.

Also, if you're using Eclipse or NetBeans, there are many design plug-ins, some of which may have the features you're looking for.

PHP session lost after redirect

Today I had this problem in a project and I had to change this parameter to false (or remove the lines, by default is disabled):

ini_set( 'session.cookie_secure', 1 );

This happened because the actual project works over http and not https only. Found more info in the docs http://php.net/manual/en/session.security.ini.php

Get a specific bit from byte

Easy. Use a bitwise AND to compare your number with the value 2^bitNumber, which can be cheaply calculated by bit-shifting.

//your black magic
var bit = (b & (1 << bitNumber-1)) != 0;

EDIT: To add a little more detail because there are a lot of similar answers with no explanation:

A bitwise AND compares each number, bit-by-bit, using an AND join to produce a number that is the combination of bits where both the first bit and second bit in that place were set. Here's the logic matrix of AND logic in a "nibble" that shows the operation of a bitwise AND:

  0101
& 0011
  ----
  0001 //Only the last bit is set, because only the last bit of both summands were set

In your case, we compare the number you passed with a number that has only the bit you want to look for set. Let's say you're looking for the fourth bit:

  11010010
& 00001000
  --------
  00000000 //== 0, so the bit is not set

  11011010
& 00001000
  --------
  00001000 //!= 0, so the bit is set

Bit-shifting, to produce the number we want to compare against, is exactly what it sounds like: take the number, represented as a set of bits, and shift those bits left or right by a certain number of places. Because these are binary numbers and so each bit is one greater power-of-two than the one to its right, bit-shifting to the left is equivalent to doubling the number once for each place that is shifted, equivalent to multiplying the number by 2^x. In your example, looking for the fourth bit, we perform:

       1 (2^0) << (4-1) ==        8 (2^3)
00000001       << (4-1) == 00001000

Now you know how it's done, what's going on at the low level, and why it works.

How can I quickly and easily convert spreadsheet data to JSON?

Assuming you really mean easiest and are not necessarily looking for a way to do this programmatically, you can do this:

  1. Add, if not already there, a row of "column Musicians" to the spreadsheet. That is, if you have data in columns such as:

    Rory Gallagher      Guitar
    Gerry McAvoy        Bass
    Rod de'Ath          Drums
    Lou Martin          Keyboards
    Donkey Kong Sioux   Self-Appointed Semi-official Stomper
    

    Note: you might want to add "Musician" and "Instrument" in row 0 (you might have to insert a row there)

  2. Save the file as a CSV file.

  3. Copy the contents of the CSV file to the clipboard

  4. Go to http://www.convertcsv.com/csv-to-json.htm

  5. Verify that the "First row is column names" checkbox is checked

  6. Paste the CSV data into the content area

  7. Mash the "Convert CSV to JSON" button

    With the data shown above, you will now have:

    [
      {
        "MUSICIAN":"Rory Gallagher",
        "INSTRUMENT":"Guitar"
      },
      {
        "MUSICIAN":"Gerry McAvoy",
        "INSTRUMENT":"Bass"
      },
      {
        "MUSICIAN":"Rod D'Ath",
        "INSTRUMENT":"Drums"
      },
      {
        "MUSICIAN":"Lou Martin",
        "INSTRUMENT":"Keyboards"
      }
      {
        "MUSICIAN":"Donkey Kong Sioux",
        "INSTRUMENT":"Self-Appointed Semi-Official Stomper"
      }
    ]
    

    With this simple/minimalistic data, it's probably not required, but with large sets of data, it can save you time and headache in the proverbial long run by checking this data for aberrations and abnormalcy.

  8. Go here: http://jsonlint.com/

  9. Paste the JSON into the content area

  10. Pres the "Validate" button.

If the JSON is good, you will see a "Valid JSON" remark in the Results section below; if not, it will tell you where the problem[s] lie so that you can fix it/them.

LD_LIBRARY_PATH vs LIBRARY_PATH

LIBRARY_PATH is used by gcc before compilation to search directories containing static and shared libraries that need to be linked to your program.

LD_LIBRARY_PATH is used by your program to search directories containing shared libraries after it has been successfully compiled and linked.

EDIT: As pointed below, your libraries can be static or shared. If it is static then the code is copied over into your program and you don't need to search for the library after your program is compiled and linked. If your library is shared then it needs to be dynamically linked to your program and that's when LD_LIBRARY_PATH comes into play.

Using only CSS, show div on hover over <a>

_x000D_
_x000D_
.showme {_x000D_
  display: none;_x000D_
}_x000D_
_x000D_
.showhim:hover .showme {_x000D_
  display: block;_x000D_
}
_x000D_
<div class="showhim">HOVER ME_x000D_
  <div class="showme">hai</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

jsfiddle

Since this answer is popular I think a small explanation is needed. Using this method when you hover on the internal element, it wont disappear. Because the .showme is inside .showhim it will not disappear when you move your mouse between the two lines of text (or whatever it is).

These are example of quirqs you need to take care of when implementing such behavior.

It all depends what you need this for. This method is better for a menu style scenario, while Yi Jiang's is better for tooltips.

Nesting await in Parallel.ForEach

The whole idea behind Parallel.ForEach() is that you have a set of threads and each thread processes part of the collection. As you noticed, this doesn't work with async-await, where you want to release the thread for the duration of the async call.

You could “fix” that by blocking the ForEach() threads, but that defeats the whole point of async-await.

What you could do is to use TPL Dataflow instead of Parallel.ForEach(), which supports asynchronous Tasks well.

Specifically, your code could be written using a TransformBlock that transforms each id into a Customer using the async lambda. This block can be configured to execute in parallel. You would link that block to an ActionBlock that writes each Customer to the console. After you set up the block network, you can Post() each id to the TransformBlock.

In code:

var ids = new List<string> { "1", "2", "3", "4", "5", "6", "7", "8", "9", "10" };

var getCustomerBlock = new TransformBlock<string, Customer>(
    async i =>
    {
        ICustomerRepo repo = new CustomerRepo();
        return await repo.GetCustomer(i);
    }, new ExecutionDataflowBlockOptions
    {
        MaxDegreeOfParallelism = DataflowBlockOptions.Unbounded
    });
var writeCustomerBlock = new ActionBlock<Customer>(c => Console.WriteLine(c.ID));
getCustomerBlock.LinkTo(
    writeCustomerBlock, new DataflowLinkOptions
    {
        PropagateCompletion = true
    });

foreach (var id in ids)
    getCustomerBlock.Post(id);

getCustomerBlock.Complete();
writeCustomerBlock.Completion.Wait();

Although you probably want to limit the parallelism of the TransformBlock to some small constant. Also, you could limit the capacity of the TransformBlock and add the items to it asynchronously using SendAsync(), for example if the collection is too big.

As an added benefit when compared to your code (if it worked) is that the writing will start as soon as a single item is finished, and not wait until all of the processing is finished.

SFTP file transfer using Java JSch

The most trivial way to upload a file over SFTP with JSch is:

JSch jsch = new JSch();
Session session = jsch.getSession(user, host);
session.setPassword(password);
session.connect();

ChannelSftp sftpChannel = (ChannelSftp) session.openChannel("sftp");
sftpChannel.connect();

sftpChannel.put("C:/source/local/path/file.zip", "/target/remote/path/file.zip");

Similarly for a download:

sftpChannel.get("/source/remote/path/file.zip", "C:/target/local/path/file.zip");

You may need to deal with UnknownHostKey exception.

Connection failed: SQLState: '01000' SQL Server Error: 10061

Received SQLSTATE 01000 in the following error message below:

SQL Agent - Jobs Failed: The SQL Agent Job "LiteSpeed Backup Full" has failed with the message "The job failed. The Job was invoked by User X. The last step to run was step 1 (Step1). NOTE: Failed to notify via email. - Executed as user: X. LiteSpeed(R) for SQL Server Version 6.5.0.1460 Copyright 2011 Quest Software, Inc. [SQLSTATE 01000] (Message 1) LiteSpeed for SQL Server could not open backup file: (N:\BACKUP2\filename.BAK). The previous system message is the reason for the failure. [SQLSTATE 42000] (Error 60405). The step failed."

In my case this was related to permission on drive N following an SQL Server failover on an Active/Passive SQL cluster.

All SQL resources where failed over to the seconary resouce and back to the preferred node following maintenance. When the Quest LiteSpeed job then executed on the preferred node it was clear the previous permissions for SQL server user X had been lost on drive N and SQLSTATE 10100 was reported.

Simply added the permissions again to the backup destination drive and the issue was resolved.

Hope that helps someone.

Windows 2008 Enterprise

SQL Server 2008 Active/Passive cluster.

Optimal way to concatenate/aggregate strings

For those of us who found this and are not using Azure SQL Database:

STRING_AGG() in PostgreSQL, SQL Server 2017 and Azure SQL
https://www.postgresql.org/docs/current/static/functions-aggregate.html
https://docs.microsoft.com/en-us/sql/t-sql/functions/string-agg-transact-sql

GROUP_CONCAT() in MySQL
http://dev.mysql.com/doc/refman/5.7/en/group-by-functions.html#function_group-concat

(Thanks to @Brianjorden and @milanio for Azure update)

Example Code:

select Id
, STRING_AGG(Name, ', ') Names 
from Demo
group by Id

SQL Fiddle: http://sqlfiddle.com/#!18/89251/1

Could not resolve placeholder in string value

In my case, I was careless while merging the application.yml file, and I've unnecessary indented my properties to the right.

I've indented it like this:

spring:
    application:
       name: applicationName
............................
    myProperties:
       property1: property1value

While the code expected it to be like this:

spring:
    application:
        name: applicationName
.............................
myProperties:
    property1: property1value

How to properly highlight selected item on RecyclerView?

Look on my solution. I suppose that you should set selected position in holder and pass it as Tag of View. The view should be set in the onCreateViewHolder(...) method. There is also correct place to set listener for view such as OnClickListener or LongClickListener.

Please look on the example below and read comments to code.

public class MyListAdapter extends RecyclerView.Adapter<MyListAdapter.ViewHolder> {
    //Here is current selection position
    private int mSelectedPosition = 0;
    private OnMyListItemClick mOnMainMenuClickListener = OnMyListItemClick.NULL;

    ...

    // constructor, method which allow to set list yourObjectList

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        //here you prepare your view 
        // inflate it
        // set listener for it
        final ViewHolder result = new ViewHolder(view);
        final View view =  LayoutInflater.from(parent.getContext()).inflate(R.layout.your_view_layout, parent, false);
        view.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                //here you set your current position from holder of clicked view
                mSelectedPosition = result.getAdapterPosition();

                //here you pass object from your list - item value which you clicked
                mOnMainMenuClickListener.onMyListItemClick(yourObjectList.get(mSelectedPosition));

                //here you inform view that something was change - view will be invalidated
                notifyDataSetChanged();
            }
        });
        return result;
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        final YourObject yourObject = yourObjectList.get(position);

        holder.bind(yourObject);
        if(mSelectedPosition == position)
            holder.itemView.setBackgroundColor(Color.CYAN);
        else
            holder.itemView.setBackgroundColor(Color.RED);
    }

    // you can create your own listener which you set for adapter
    public void setOnMainMenuClickListener(OnMyListItemClick onMyListItemClick) {
        mOnMainMenuClickListener = onMyListItemClick == null ? OnMyListItemClick.NULL : onMyListItemClick;
    }

    static class ViewHolder extends RecyclerView.ViewHolder {


        ViewHolder(View view) {
            super(view);
        }

        private void bind(YourObject object){
            //bind view with yourObject
        }
    }

    public interface OnMyListItemClick {
        OnMyListItemClick NULL = new OnMyListItemClick() {
            @Override
            public void onMyListItemClick(YourObject item) {

            }
        };

        void onMyListItemClick(YourObject item);
    }
}

Remove by _id in MongoDB console

Well, the _id is an object in your example, so you just need to pass an object

'db.test_users.remove({"_id": { "$oid" : "4d513345cc9374271b02ec6c" }})'

This should work

Edit: Added trailing paren to ensure that it compiled.

forEach() in React JSX does not output any HTML

You need to pass an array of element to jsx. The problem is that forEach does not return anything (i.e it returns undefined). So it's better to use map because map returns an array:

class QuestionSet extends Component {
render(){ 
    <div className="container">
       <h1>{this.props.question.text}</h1>
       {this.props.question.answers.map((answer, i) => {     
           console.log("Entered");                 
           // Return the element. Also pass key     
           return (<Answer key={answer} answer={answer} />) 
        })}
}

export default QuestionSet;

Detect if Visual C++ Redistributable for Visual Studio 2012 is installed

The answer to this simple questions is unfortunately not a simple one, but working in 100% of all systems, and even extendable to the numerous .net frameworks.

The complexity comes from the fact that there are (and were) many VC runtimes revisions which could lead to the case that although VC10 runtimes were installed, their build number was not recent enough so your EXE wouldn't start unless you either installed the very exact runtimes you required or one of the newer runtimes which enable this and previous versions for the same major version to run with it (the side-by-side hell). Also, if you have a 64 bit EXE, you will have to check for both, the 32 AND 64 bit runtimes.

That said, the only reliable way to determine whether the runtimes for your EXE are installed is to attempt to run the EXE - or a another EXE which is built with the same settings as your main EXE and whose only purpose is to do - nothing. Just run (which means the runtimes are installed) or fail to run (when not installed).

I did the following for an installer which required the VC10 32 and 64 bit runtimes installed: The installer attempts to launch all dummy EXEs and if it succeeds, the corresponding runtime is considered to be installed. This also resolves the 32/64 bit scenario.

This, by the way, works also to determine if the proper .net framework is installed, which is very tricky in Windows 8 and 10, as the downloadable built-in .net 3.5 support also supports the .net versions 3.0 and 2.0 - there are no registry entries for these. (And worse, you cannot even use the standard framework installers here, you must use the built-in support and download it via Windows, or rebuild your app with .net 4, but that's another story).

The C++ dummy EXE can be built using a project with the following code (and another one in a 64 bit configuration if necessary):

int _tmain(int argc, _TCHAR* argv[])
{
    return 0;
}

Remember to set the project's properties Use of MFC to Use MFC in a shared DLL. The executables will be around 4KB in size - a small price to pay for a sure result.

To give your users a nice installation experience, you could do the following (sample code is for NSIS):

Function TryLaunchApplication
  Pop $1 ; pathname
  nsExec::Exec $1
  Pop $0

  ${If} $0 == "error"
  ${OrIf} $0 != 0
    Push 0
  ${Else}
    Push 1
  ${EndIf}
FunctionEnd

and call it in a function, e.g. CheckRuntimes

Function CheckRuntimes
  ; Try to execute VC++ 10 application (32 bit)
  Push "Vc10RuntimeCheckerApp.exe"
  Call TryLaunchApplication
  Pop $Vc10RuntimesFound

  ; Add 64 bit check if required.
  ; Remember to try running the 64 bit EXE only on a 64 bit OS,
  ; which requires further checks.

  ; Try to execute .net application
  Push "DotNetRuntimeCheckerApp.exe"
  Call TryLaunchApplication
  Pop $DotNetFrameworkFound
FunctionEnd

Then launch the runtime check e.g. when leaving the Welcome page and cache the result, so you don't have to re-check every time the user clicks on the "Back" and "Next" button.

Next, make a read-only section in the install tree and pre-select or unselect it on the a function which is executed before the Components page is shown.

This will make sure that the installation of each missing runtime component is mandatory, and is skipped if it is already present.

Setting an int to Infinity in C++

This is a message for me in the future:

Just use: (unsigned)!((int)0)

It creates the largest possible number in any machine by assigning all bits to 1s (ones) and then casts it to unsigned

Even better

#define INF (unsigned)!((int)0)

And then just use INF in your code

Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect)

check if the object exists or not in DB, if it exists get the object and refresh it:

if (getEntityManager().contains(instance)) {
    getEntityManager().refresh(instance);
    return instance;
}

if it fails the above if condition... find the Object with Id in DB, do the operation which you need, in this case exactly changes will reflects.

if (....) {
    } else if (null != identity) {
        E dbInstance = (E) getEntityManager().find(instance.getClass(), identity);
        return dbInstance;
    }

Output Django queryset as JSON

from django.http import JsonResponse

def SomeFunction(): dict1 = {}

   obj = list( Mymodel.objects.values() )

   dict1['data']=obj

return JsonResponse(dict1)

Try this code for Django

Function not defined javascript

There are a couple of things to check:

  • In FireBug, see if there are any loading errors that would indicate that your script is badly formatted and the functions do not get registered.
  • You can also try typing "proceedToSecond" into the FireBug console to see if the function gets defined
  • One thing you may try is removing the space around the @type attribute to the script tag: it should be <script type="text/javascript"> instead of <script type = "text/javascript">

what is the use of "response.setContentType("text/html")" in servlet

From JavaEE docs ServletResponse#setContentType

  • Sets the content type of the response being sent to the client, if the response has not been committed yet.

  • The given content type may include a character encoding specification, for example,

response.setContentType("text/html;charset=UTF-8");

  • The response's character encoding is only set from the given content type if this method is called before getWriter is called.

  • This method may be called repeatedly to change content type and character encoding.

  • This method has no effect if called after the response has been committed. It does not set the response's character encoding if it is called after getWriter has been called or after the response has been committed.

  • Containers must communicate the content type and the character encoding used for the servlet response's writer to the client if the protocol provides a way for doing so. In the case of HTTP, the Content-Type header is used.

Remove #N/A in vlookup result

If you only want to return a blank when B2 is blank you can use an additional IF function for that scenario specifically, i.e.

=IF(B2="","",VLOOKUP(B2,Index!A1:B12,2,FALSE))

or to return a blank with any error from the VLOOKUP (e.g. including if B2 is populated but that value isn't found by the VLOOKUP) you can use IFERROR function if you have Excel 2007 or later, i.e.

=IFERROR(VLOOKUP(B2,Index!A1:B12,2,FALSE),"")

in earlier versions you need to repeat the VLOOKUP, e.g.

=IF(ISNA(VLOOKUP(B2,Index!A1:B12,2,FALSE)),"",VLOOKUP(B2,Index!A1:B12,2,FALSE))

JSON serialization/deserialization in ASP.Net Core

You can use Newtonsoft.Json, it's a dependency of Microsoft.AspNet.Mvc.ModelBinding which is a dependency of Microsoft.AspNet.Mvc. So, you don't need to add a dependency in your project.json.

#using Newtonsoft.Json
....
JsonConvert.DeserializeObject(json);

Note, using a WebAPI controller you don't need to deal with JSON.

UPDATE ASP.Net Core 3.0

Json.NET has been removed from the ASP.NET Core 3.0 shared framework.

You can use the new JSON serializer layers on top of the high-performance Utf8JsonReader and Utf8JsonWriter. It deserializes objects from JSON and serializes objects to JSON. Memory allocations are kept minimal and includes support for reading and writing JSON with Stream asynchronously.

To get started, use the JsonSerializer class in the System.Text.Json.Serialization namespace. See the documentation for information and samples.

To use Json.NET in an ASP.NET Core 3.0 project:

    services.AddMvc()
        .AddNewtonsoftJson();

Read Json.NET support in Migrate from ASP.NET Core 2.2 to 3.0 Preview 2 for more information.

Printing out a linked list using toString

When the JVM tries to run your application, it calls your main method statically; something like this:

LinkedList.main();

That means there is no instance of your LinkedList class. In order to call your toString() method, you can create a new instance of your LinkedList class.

So the body of your main method should be like this:

public static void main(String[] args){
    // creating an instance of LinkedList class
    LinkedList ll = new LinkedList();

    // adding some data to the list
    ll.insertFront(1);
    ll.insertFront(2);
    ll.insertFront(3);
    ll.insertBack(4);

    System.out.println(ll.toString());
}

Can you autoplay HTML5 videos on the iPad?

I want to start by saying by saying that I realize this question is old and already has an accepted answer; but, as an unfortunate internet user that used this question as a means to end only to be proven wrong shortly after (but not before I upset my client a little) I want to add my thoughts and suggestions.

While @DSG and @Giona are correct, and there is nothing wrong with their answers, there is a creative mechanism you can employ to "get around," so to speak, this limitation. That is not say that I'm condoning circumvention of this feature, quite the contrary, but just some mechanisms so that a user still "feels" as if a video or audio file is "auto playing."

The quick work around is hide a video tag somewhere on the mobile page, since I built a responsive site I only do this for smaller screens. The video tag (HTML and jQuery examples):

HTML

<video id="dummyVideo" src="" preload="none" width="1" height="2"></video>

jQuery

var $dummyVideo = $("<video />", {
  id: "dummyVideo",
  src: "",
  preload: "none",
  width: "1",
  height: "2"
});

With that hidden on the page, when a user "clicks" to watch a movie (still user interaction, there is no way to get around that requirement) instead of navigating to a secondary watch page I load the hidden video. This mainly works because the media tag isn't really used but instead promoted to a Quicktime instance so having a visible video element isn't necessary at all. In the handler for "click" (or "touchend" on mobile).

$(".movie-container").on("click", function() {
  var url = $(this).data("stream-url");
  $dummyVideo.attr("src", url);
  $dummyVideo.get(0).load(); // required if src changed after page load
  $dummyVideo.get(0).play();
});

And viola. As far as UX goes, a user clicks on a video to play and Quicktime opens playing the video they chose. This remains within the limitation that videos can only be played via user action so I'm not forcing data on anyone who isn't deciding to watch a video with this service. I discovered this when trying to figure out how exactly Youtube pulled this off with their mobile which is essentially some really nice Javascript page building and fancy element hiding like in the case of the video tag.

tl;dr Here is a somewhat "workaround" to try and create an "autoplay" UX feature on iOS devices without going above and beyond Apple's limitations and still having users decide if they want to watch a video (or audio most likey, though I've not tested) themselves without having one just loaded without their permission.

Also, to the person who commented that is from sleep.fm, this still unfortunately would not have been a solution to your issues which is time based audio play back.

I hope someone finds this information useful, it would have saved me a week of bad news delivery to a client that was adamant that they have this feature and I was glad to find a way to deliver it in the end.

EDIT

Further finding indicate the above workaround is for iPhone/iPod devices only. The iPad plays video in Safari before it's been full screened so you'll need some mechanism to resize the video on click before playing or else you'll end up with audio and no video.

How do I change the font size of a UILabel in Swift?

I used fontWithSize for a label with light system font, but it changes back to normal system font.

If you want to keep the font's traits, better to include the descriptors.

label.font = UIFont(descriptor: label.font.fontDescriptor(), size: 16.0)

How to implement a Map with multiple keys?

all multy key's probably fail, cause the put([key1, key2], val) and the get([null, key2]) end up using the equals of [key1, key2] and [null, key2]. If the backing map doesnt contains hash buckets per key then lookups are real slow to.

i think the way to go is using a index decorator (see the key1, key2 examples above) and if the extra index key's are properties of the stored value you can use the property name's and reflection to build the secondairy maps when you put(key, val) and add an extra method get(propertyname, propertyvalue) to use that index.

the return type of the get(propertyname, propertyvalue) could be a Collection so even none unique key's are indexed....

java.net.ConnectException: localhost/127.0.0.1:8080 - Connection refused

You just have to use your local IP address:using the cmd command "ipconfig" and your server port number like this:

String webServiceUrl = "http://192.168.X.X:your_local_server_port/your_web_service_name.php"

And make sure you did set the internet permission in your project manifest

It's working perfectly for me

Good Luck

PHP PDO with foreach and fetch

A PDOStatement (which you have in $users) is a forward-cursor. That means, once consumed (the first foreach iteration), it won't rewind to the beginning of the resultset.

You can close the cursor after the foreach and execute the statement again:

$users       = $dbh->query($sql);
foreach ($users as $row) {
    print $row["name"] . "-" . $row["sex"] ."<br/>";
}

$users->execute();

foreach ($users as $row) {
    print $row["name"] . "-" . $row["sex"] ."<br/>";
}

Or you could cache using tailored CachingIterator with a fullcache:

$users       = $dbh->query($sql);

$usersCached = new CachedPDOStatement($users);

foreach ($usersCached as $row) {
    print $row["name"] . "-" . $row["sex"] ."<br/>";
}
foreach ($usersCached as $row) {
    print $row["name"] . "-" . $row["sex"] ."<br/>";
}

You find the CachedPDOStatement class as a gist. The caching itertor is probably more sane than storing the resultset into an array because it still offers all properties and methods of the PDOStatement object it has wrapped.

Unable to instantiate default tuplizer [org.hibernate.tuple.entity.PojoEntityTuplizer]

I was getting the same error even after adding no-arg constructor,Then I figured out that I was missing several JARs.I am posting this so that if anyone gets the error like I got, make sure you have added these JARs in your lib folder :

activation-1.0.2.jar
antlr-2.7.6.jar
aopalliance.jar
asm-1.5.3.jar
asm-attrs-1.5.3.jar
cglib-2.1_3.jar
commons-beanutils-1.7.0.jar
commons-collections-2.1.1.jar
commons-digester-1.8.jar
commons-email-1.0.jar
commons-fileupload-1.1.1.jar
commons-io-1.1.jar
commons-lang-2.5.jar
commons-logging-1.1.3.jar
dom4j-1.6.1.jar
dumbster-1.6.jar
ehcache-1.2.3.jar
ejb3-persistence-3.3.1.jar
hibernate-commons-annotations-4.0.4.Final.jar
hibernate-core-4.2.8.Final.jar
icu4j-2.6.1.jar
javassist-3.4.GA.jar
javax.persistence_2.0.3.v201010191057.jar
javax.servlet.jsp.jstl-1.2.1.jar
jaxb-api-2.1.jar
jaxb-impl-2.1.3.jar
jaxen-1.1.1.jar
jboss-logging-3.1.3.GA.jar
jdom-1.0.jar
jstl-1.2.jar
jta-1.1.jar
lucene-core-2.3.2.jar
lucene-highlighter-2.0.0.jar
mail-1.4.jar
mysql-connector-java-5.0.8-bin.jar
org.springframework.orm.jar
slf4j-api-1.6.1.jar
slf4j-log4j12-1.5.6.jar
spring-aop-4.0.0.RELEASE.jar
spring-aspects-4.0.0.RELEASE-javadoc.jar
spring-beans-4.0.0.RELEASE.jar
spring-build-src-4.0.0.RELEASE.jar
spring-context-4.0.0.RELEASE.jar
spring-core-4.0.0.RELEASE.jar
spring-expression-4.0.0.RELEASE.jar
spring-framework-bom-4.0.0.RELEASE.jar
spring-jdbc-4.0.0.RELEASE.jar
spring-orm-4.0.0.RELEASE.jar
spring-tx-4.0.0.RELEASE.jar
spring-web-4.0.0.RELEASE.jar
spring-webmvc-4.0.0.RELEASE.jar
stax-api-1.0-2.jar
validation-api-1.0.0.GA.jar
xalan-2.6.0.jar
xercesImpl-2.6.2.jar
xml-apis-1.3.02.jar
xmlParserAPIs-2.6.2.jar
xom-1.0.jar

'Malformed UTF-8 characters, possibly incorrectly encoded' in Laravel

In my case, this causes error:

return response->json(["message" => "Model status successfully updated!", "data" => $model], 200);

but this not:

return response->json(["message" => "Model status successfully updated!", "data" => $model->toJson()], 200);

Java BigDecimal: Round to the nearest whole value

If i go by Grodriguez's answer

System.out.println("" + value);
value = value.setScale(0, BigDecimal.ROUND_HALF_UP);
System.out.println("" + value);

This is the output

100.23 -> 100
100.77 -> 101

Which isn't quite what i want, so i ended up doing this..

System.out.println("" + value);
value = value.setScale(0, BigDecimal.ROUND_HALF_UP);
value = value.setScale(2, BigDecimal.ROUND_HALF_UP);
System.out.println("" + value);

This is what i get

100.23 -> 100.00
100.77 -> 101.00

This solves my problem for now .. : ) Thank you all.

How to Decrease Image Brightness in CSS

try this if you need to convert black image into white:

.classname{
    filter: brightness(0) invert(1);
}

How to compare character ignoring case in primitive types

Generic methods to compare a char at a position between 2 strings with ignore case.

public static boolean isEqualIngoreCase(char one, char two){
    return Character.toLowerCase(one)==Character .toLowerCase(two);
}

public static boolean isEqualStringCharIgnoreCase(String one, String two, int position){
    char oneChar = one.charAt(position);
    char twoChar = two.charAt(position);
    return isEqualIngoreCase(oneChar, twoChar);
}

Function call

boolean isFirstCharEqual = isEqualStringCharIgnoreCase("abc", "ABC", 0)

SSRS the definition of the report is invalid

This occurred for me due to changing the names of certain dataset fields within BIDS that were being referenced by parameters. I forgot to go into the parameters and reassign a default value (the default value of the parameter didn't automatically change to the newly renamed dataset field. Instead .

How to replace multiple white spaces with one white space

You can try this:

    /// <summary>
    /// Remove all extra spaces and tabs between words in the specified string!
    /// </summary>
    /// <param name="str">The specified string.</param>
    public static string RemoveExtraSpaces(string str)
    {
        str = str.Trim();
        StringBuilder sb = new StringBuilder();
        bool space = false;
        foreach (char c in str)
        {
            if (char.IsWhiteSpace(c) || c == (char)9) { space = true; }
            else { if (space) { sb.Append(' '); }; sb.Append(c); space = false; };
        }
        return sb.ToString();
    }

Oracle Insert via Select from multiple tables where one table may not have a row

A slightly simplified version of Oglester's solution (the sequence doesn't require a select from DUAL:

INSERT INTO account_type_standard   
  (account_type_Standard_id, tax_status_id, recipient_id) 
VALUES(   
  account_type_standard_seq.nextval,
  (SELECT tax_status_id FROM tax_status WHERE tax_status_code = ?),
  (SELECT recipient_id FROM recipient WHERE recipient_code = ?)
)

Git - What is the difference between push.default "matching" and "simple"

Git v2.0 Release Notes

Backward compatibility notes

When git push [$there] does not say what to push, we have used the traditional "matching" semantics so far (all your branches were sent to the remote as long as there already are branches of the same name over there). In Git 2.0, the default is now the "simple" semantics, which pushes:

  • only the current branch to the branch with the same name, and only when the current branch is set to integrate with that remote branch, if you are pushing to the same remote as you fetch from; or

  • only the current branch to the branch with the same name, if you are pushing to a remote that is not where you usually fetch from.

You can use the configuration variable "push.default" to change this. If you are an old-timer who wants to keep using the "matching" semantics, you can set the variable to "matching", for example. Read the documentation for other possibilities.

When git add -u and git add -A are run inside a subdirectory without specifying which paths to add on the command line, they operate on the entire tree for consistency with git commit -a and other commands (these commands used to operate only on the current subdirectory). Say git add -u . or git add -A . if you want to limit the operation to the current directory.

git add <path> is the same as git add -A <path> now, so that git add dir/ will notice paths you removed from the directory and record the removal. In older versions of Git, git add <path> used to ignore removals. You can say git add --ignore-removal <path> to add only added or modified paths in <path>, if you really want to.

Question mark characters displaying within text, why is this?

This is going to be something to do with character encodings.

Are you sure the mirrored site has the same properties with regards to character encodings as your main server?

Depending on what sort of server you have, this may be a property of the server process itself, or it could be an environment variable.

For example, if this is a UNIX environment, perhaps try comparing LANG or LC_ALL?

See also here

Manually raising (throwing) an exception in Python

You should learn the raise statement of python for that. It should be kept inside the try block. Example -

try:
    raise TypeError            #remove TypeError by any other error if you want
except TypeError:
    print('TypeError raised')

How do I show running processes in Oracle DB?

Keep in mind that there are processes on the database which may not currently support a session.

If you're interested in all processes you'll want to look to v$process (or gv$process on RAC)

Quick way to retrieve user information Active Directory

You can simplify this code to:

        DirectorySearcher searcher = new DirectorySearcher();
        searcher.Filter = "(&(objectCategory=user)(cn=steve.evans))";

        SearchResultCollection results = searcher.FindAll();

        if (results.Count == 1)
        {
            //do what you want to do
        }
        else if (results.Count == 0)
        {
            //user does not exist
        }
        else
        {
            //found more than one user
            //something is wrong
        }

If you can narrow down where the user is you can set searcher.SearchRoot to a specific OU that you know the user is under.

You should also use objectCategory instead of objectClass since objectCategory is indexed by default.

You should also consider searching on an attribute other than CN. For example it might make more sense to search on the username (sAMAccountName) since it's guaranteed to be unique.

Why is it important to override GetHashCode when Equals method is overridden?

Hash code is used for hash-based collections like Dictionary, Hashtable, HashSet etc. The purpose of this code is to very quickly pre-sort specific object by putting it into specific group (bucket). This pre-sorting helps tremendously in finding this object when you need to retrieve it back from hash-collection because code has to search for your object in just one bucket instead of in all objects it contains. The better distribution of hash codes (better uniqueness) the faster retrieval. In ideal situation where each object has a unique hash code, finding it is an O(1) operation. In most cases it approaches O(1).

TypeError: $(...).DataTable is not a function

I ran into this error also. For whatever reason I had originally coded

var table = $('#myTable').DataTable({
    "paging": false,
    "order": [[ 4, "asc" ]]
});

This would not throw the error sometimes and other times it would. By changing code to

$('#myTable').DataTable({
    "paging": false,
    "order": [[ 4, "asc" ]]
});

Error appears to have stopped

Adding a new array element to a JSON object

var Str_txt = '{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}';

If you want to add at last position then use this:

var parse_obj = JSON.parse(Str_txt);
parse_obj['theTeam'].push({"teamId":"4","status":"pending"});
Str_txt = JSON.stringify(parse_obj);
Output //"{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"},{"teamId":"4","status":"pending"}]}"

If you want to add at first position then use the following code:

var parse_obj = JSON.parse(Str_txt);
parse_obj['theTeam'].unshift({"teamId":"4","status":"pending"});
Str_txt = JSON.stringify(parse_obj);
Output //"{"theTeam":[{"teamId":"4","status":"pending"},{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}"

Anyone who wants to add at a certain position of an array try this:

parse_obj['theTeam'].splice(2, 0, {"teamId":"4","status":"pending"});
Output //"{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"4","status":"pending"},{"teamId":"3","status":"member"}]}"

Above code block adds an element after the second element.

Calendar date to yyyy-MM-dd format in java

I found this code where date is compared in a format to compare with date field in database...may be this might be helpful to you...

When you convert the string to date using simpledateformat, it is hard to compare with the Date field in mysql databases.

So convert the java string date in the format using select STR_to_DATE('yourdate','%m/%d/%Y') --> in this format, then you will get the exact date format of mysql date field.

http://javainfinite.com/java/java-convert-string-to-date-and-compare/