Programs & Examples On #Sdk3.0

Need a good hex editor for Linux

wxHexEditor is the only GUI disk editor for linux. to google "wxhexeditor site:archive.getdeb.net" and download the .deb file to install

Split string into string array of single characters

Try this:

var charArray = "this is a test".ToCharArray().Select(c=>c.ToString());

Regex pattern for numeric values

This will allow decimal numbers (or whole numbers) that don't start with zero:

^(([1-9]*)|(([1-9]*)\.([0-9]*)))$

If you want to allow numbers that start with zero, you can do :

^(([0-9]*)|(([0-9]*)\.([0-9]*)))$

ubuntu "No space left on device" but there is tons of space

It's possible that you've run out of memory or some space elsewhere and it prompted the system to mount an overflow filesystem, and for whatever reason, it's not going away.

Try unmounting the overflow partition:

umount /tmp

or

umount overflow

top -c command in linux to filter processes listed based on processname

After looking for so many answers on StackOverflow, I haven't seen an answer to fit my needs.

That is, to make top command to keep refreshing with given keyword, and we don't have to CTRL+C / top again and again when new processes spawn.

Thus I make a new one...

Here goes the no-restart-needed version.

__keyword=name_of_process; (while :; do __arg=$(pgrep -d',' -f $__keyword); if [ -z "$__arg" ]; then top -u 65536 -n 1; else top -c -n 1 -p $__arg; fi; sleep 1; done;)

Modify the __keyword and it should works. (Ubuntu 2.6.38 tested)

2.14.2015 added: The system workload part is missing with the code above. For people who cares about the "load average" part:

__keyword=name_of_process; (while :; do __arg=$(pgrep -d',' -f $__keyword); if [ -z "$__arg" ]; then top -u 65536 -n 1; else top -c -n 1 -p $__arg; fi; uptime; sleep 1; done;)

db.collection is not a function when using MongoClient v3.0

I did a little experimenting to see if I could keep the database name as part of the url. I prefer the promise syntax but it should still work for the callback syntax. Notice below that client.db() is called without passing any parameters.

MongoClient.connect(
    'mongodb://localhost:27017/mytestingdb', 
    { useNewUrlParser: true}
)
.then(client => {

    // The database name is part of the url.  client.db() seems 
    // to know that and works even without a parameter that 
    // relays the db name.
    let db = client.db(); 

    console.log('the current database is: ' + db.s.databaseName);
    // client.close() if you want to

})
.catch(err => console.log(err));

My package.json lists monbodb ^3.2.5.

The 'useNewUrlParser' option is not required if you're willing to deal with a deprecation warning. But it is wise to use at this point until version 4 comes out where presumably the new driver will be the default and you won't need the option anymore.

Get checkbox list values with jQuery

You should use map for this.

$('input[type=checkbox]:checked').map(function(i, e) { 
    return $(e).val(); 
});

How to change status bar color to match app in Lollipop? [Android]

Add this line in style of v21 if you use two style.

  <item name="android:statusBarColor">#43434f</item>

How do I display a ratio in Excel in the format A:B?

Try this formula:

=SUBSTITUTE(TEXT(A1/B1,"?/?"),"/",":")

Result:

A   B   C
33  11  3:1
25  5   5:1
6   4   3:2

Explanation:

  • TEXT(A1/B1,"?/?") turns A/B into an improper fraction
  • SUBSTITUTE(...) replaces the "/" in the fraction with a colon

This doesn't require any special toolkits or macros. The only downside might be that the result is considered text--not a number--so you can easily use it for further calculations.


Note: as @Robin Day suggested, increase the number of question marks (?) as desired to reduce rounding (thanks Robin!).

Java String.split() Regex

You could split on a word boundary with \b

add class with JavaScript

I like to use a custom "foreach" function of sorts for these kinds of things:

function Each( objs, func )
{
    if ( objs.length ) for ( var i = 0, ol = objs.length, v = objs[ 0 ]; i < ol && func( v, i ) !== false; v = objs[ ++i ] );
    else for ( var p in objs ) if ( func( objs[ p ], p ) === false ) break;
}

(Can't remember where I found the above function, but it has been quite useful.)

Then after fetching your objects (to elements in this example) just do

Each( elements, function( element )
{
    element.addEventListener( "mouseover", function()
    {
        element.classList.add( "active" );
        //element.setAttribute( "class", "active" );
        element.setAttribute( "src", "newsource" );
    });

    // Remove class and new src after "mouseover" ends, if you wish.
    element.addEventListener( "mouseout", function()
    {
        element.classList.remove( "active" );
        element.setAttribute( "src", "originalsource" );
    });
});

classList is a simple way for handling elements' classes. Just needs a shim for a few browsers. If you must use setAttribute you must remember that whatever is set with it will overwrite the previous values.

EDIT: Forgot to mention that you need to use attachEvent instead of addEventListener on some IE versions. Test with if ( document.addEventListener ) {...}.

jquery function setInterval

Don't pass the result of swapImages to setInterval by invoking it. Just pass the function, like this:

setInterval(swapImages, 1000);

Radio button validation in javascript

<form action="" method="post" name="register_form" id="register_form" enctype="multipart/form-data">

    <div class="text-input">
        <label>Gender: </label>
        <input class="form-control" type="radio" name="gender" id="male" value="male" />
        <label for="male">Male</label>
        <input class="form-control" type="radio" name="gender" id="female" value="female" />
        <label for="female">Female</label>
    </div>
    <div class="text-input" align="center">
        <input type="submit" name="register" value="Submit" onclick="return radioValidation();" />
    </div>

</form>

<script type="text/javascript">
    function radioValidation(){

        var gender = document.getElementsByName('gender');
        var genValue = false;

        for(var i=0; i<gender.length;i++){
            if(gender[i].checked == true){
                genValue = true;    
            }
        }
        if(!genValue){
            alert("Please Choose the gender");
            return false;
        }

    }
</script>

Source: http://chandreshrana.blogspot.in/2016/11/radio-button-validation-in-javascript.html

Laravel: Using try...catch with DB::transaction()

In the case you need to manually 'exit' a transaction through code (be it through an exception or simply checking an error state) you shouldn't use DB::transaction() but instead wrap your code in DB::beginTransaction and DB::commit/DB::rollback():

DB::beginTransaction();

try {
    DB::insert(...);
    DB::insert(...);
    DB::insert(...);

    DB::commit();
    // all good
} catch (\Exception $e) {
    DB::rollback();
    // something went wrong
}

See the transaction docs.

How to extract svg as file from web page

I don't know if this already been answered correctly or not. Well. Downloading the file from the source is not the resolution. How to grab *.svg from URL.

I installed 'svg-grabber' add-on to Google Chrome. That only partially resolve my problem, as Google Chrome does not have the shortcut to 'Back' one page.

I was trying to download the files from URL, but I kept getting an error, that there are no svg files on this page when I can see 40 of them. You can click on them, so they will open, but you cannot save it.

The folder within WordPress: .../static/img/icons/

I added 'Go Back With Backspace' add-on to Chrome, as I had to click on each file separately, as if they are white icons (that I am currently looking for), you will not see them. You have to click on the file. Then back. It was taking too long. Now is fine. There is a soft to download specific folder, but I do not want to download half of the internet, to just have get a white .

When you click on a white icon, a new tab opens, but it is all white. Then you click on svg-grabber icon in Chrome and it will open it in a new window on a black background with a button download all svg.

jQuery.ajax handling continue responses: "success:" vs ".done"?

If you need async: false in your ajax, you should use success instead of .done. Else you better to use .done. This is from jQuery official site:

As of jQuery 1.8, the use of async: false with jqXHR ($.Deferred) is deprecated; you must use the success/error/complete callback options instead of the corresponding methods of the jqXHR object such as jqXHR.done().

How to load a controller from another controller in codeigniter?

you cannot call a controller method from another controller directly

my solution is to use inheritances and extend your controller from the library controller

class Controller1 extends CI_Controller {

    public function index() {
        // some codes here
    }

    public function methodA(){
        // code here
    }
}

in your controller we call it Mycontoller it will extends Controller1

include_once (dirname(__FILE__) . "/controller1.php");

class Mycontroller extends Controller1 {

    public function __construct() {
        parent::__construct();
    }

    public function methodB(){
        // codes....
    }
}

and you can call methodA from mycontroller

http://example.com/mycontroller/methodA

http://example.com/mycontroller/methodB

this solution worked for me

Mock HttpContext.Current in Test Init Method

Below Test Init will also do the job.

[TestInitialize]
public void TestInit()
{
  HttpContext.Current = new HttpContext(new HttpRequest(null, "http://tempuri.org", null), new HttpResponse(null));
  YourControllerToBeTestedController = GetYourToBeTestedController();
}

Initialize static variables in C++ class?

They can't be initialised inside the class, but they can be initialised outside the class, in a source file:

// inside the class
class Thing {
    static string RE_ANY;
    static string RE_ANY_RELUCTANT;
};

// in the source file
string Thing::RE_ANY = "([^\\n]*)";
string Thing::RE_ANY_RELUCTANT = "([^\\n]*?)";

Update

I've just noticed the first line of your question - you don't want to make those functions static, you want to make them const. Making them static means that they are no longer associated with an object (so they can't access any non-static members), and making the data static means it will be shared with all objects of this type. This may well not be what you want. Making them const simply means that they can't modify any members, but can still access them.

How to change language settings in R

If you want to change R's language in terminal to English forever, this works fine for me in macOS:

Open terminal.app, and say:

touch .bash_profile

Then say:

open -a TextEdit.app .bash_profile

These two commands will help you open ".bash_profile" file in TextEdit.

Add this to ".bash_profile" file:

export LANG=en_US.UTF-8

Then save the file, reopen terminal and type R, you will find it's language has changed to english.

If you want language come back to it's original, just simply add a # before export LANG=en_US.UTF-8.

How can I use xargs to copy files that have spaces and quotes in their names?

I have found that the following syntax works well for me.

find /usr/pcapps/ -mount -type f -size +1000000c | perl -lpe ' s{ }{\\ }g ' | xargs ls -l | sort +4nr | head -200

In this example, I am looking for the largest 200 files over 1,000,000 bytes in the filesystem mounted at "/usr/pcapps".

The Perl line-liner between "find" and "xargs" escapes/quotes each blank so "xargs" passes any filename with embedded blanks to "ls" as a single argument.

Android overlay a view ontop of everything?

You can use bringToFront:

    View view=findViewById(R.id.btnStartGame);
    view.bringToFront();

How do I undo the most recent local commits in Git?

git revert commit

This will generate the opposite changes from the commit which you want to revert back, and then just commit that changes. I think this is the simplest way.

https://git-scm.com/docs/git-revert

How to do a deep comparison between 2 objects with lodash?

Deep compare using a template of (nested) properties to check

function objetcsDeepEqualByTemplate(objectA, objectB, comparisonTemplate) {
  if (!objectA || !objectB) return false

  let areDifferent = false
  Object.keys(comparisonTemplate).some((key) => {
    if (typeof comparisonTemplate[key] === 'object') {
      areDifferent = !objetcsDeepEqualByTemplate(objectA[key], objectB[key], comparisonTemplate[key])
      return areDifferent
    } else if (comparisonTemplate[key] === true) {
      areDifferent = objectA[key] !== objectB[key]
      return areDifferent
    } else {
      return false
    }
  })

  return !areDifferent
}

const objA = { 
  a: 1,
  b: {
    a: 21,
    b: 22,
  },
  c: 3,
}

const objB = { 
  a: 1,
  b: {
    a: 21,
    b: 25,
  },
  c: true,
}

// template tells which props to compare
const comparisonTemplateA = {
  a: true,
  b: {
    a: true
  }
}
objetcsDeepEqualByTemplate(objA, objB, comparisonTemplateA)
// returns true

const comparisonTemplateB = {
  a: true,
  c: true
}
// returns false
objetcsDeepEqualByTemplate(objA, objB, comparisonTemplateB)

This will work in the console. Array support could be added if needed

Recursively list files in Java

I came up with this for printing all the files/file names recursively.

private static void printAllFiles(String filePath,File folder) {
    if(filePath==null) {
        return;
    }
    File[] files = folder.listFiles();
    for(File element : files) {
        if(element.isDirectory()) {
            printAllFiles(filePath,element);
        } else {
            System.out.println(" FileName "+ element.getName());
        }
    }
}

How to convert Django Model object to dict with its fields and values?

The easier way is to just use pprint, which is in base Python

import pprint
item = MyDjangoModel.objects.get(name = 'foo')
pprint.pprint(item.__dict__, indent = 4)

This gives output that looks similar to json.dumps(..., indent = 4) but it correctly handles the weird data types that might be embedded in your model instance, such as ModelState and UUID, etc.

Tested on Python 3.7

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.

How to find a number in a string using JavaScript?

You can also try this :

_x000D_
_x000D_
var string = "border-radius:10px 20px 30px 40px";_x000D_
var numbers = string.match(/\d+/g).map(Number);_x000D_
console.log(numbers)
_x000D_
_x000D_
_x000D_

ASP.NET Core - Swashbuckle not creating swagger.json file

Personally I had the same issue and when I tried again today after a while I found in the new version (2.5.0) that going in the json I could see an explanation of the error that was in here.

Also another thing that helped to fix it to me was removing the hosting information connected to the website that is hold inside "..vs\config\applicationhost.config" at the root of the solution folder

I removed the element that was configuring the website.

           <site name="**" id="9">
              <application path="/" applicationPool=""></application>
              <bindings></bindings>
           </site>

How to display pandas DataFrame of floats using a format string for columns?

You can also set locale to your region and set float_format to use a currency format. This will automatically set $ sign for currency in USA.

import locale

locale.setlocale(locale.LC_ALL, "en_US.UTF-8")

pd.set_option("float_format", locale.currency)

df = pd.DataFrame(
    [123.4567, 234.5678, 345.6789, 456.7890],
    index=["foo", "bar", "baz", "quux"],
    columns=["cost"],
)
print(df)

        cost
foo  $123.46
bar  $234.57
baz  $345.68
quux $456.79

Python initializing a list of lists

The problem is that they're all the same exact list in memory. When you use the [x]*n syntax, what you get is a list of n many x objects, but they're all references to the same object. They're not distinct instances, rather, just n references to the same instance.

To make a list of 3 different lists, do this:

x = [[] for i in range(3)]

This gives you 3 separate instances of [], which is what you want

[[]]*n is similar to

l = []
x = []
for i in range(n):
    x.append(l)

While [[] for i in range(3)] is similar to:

x = []
for i in range(n):
    x.append([])   # appending a new list!

In [20]: x = [[]] * 4

In [21]: [id(i) for i in x]
Out[21]: [164363948, 164363948, 164363948, 164363948] # same id()'s for each list,i.e same object


In [22]: x=[[] for i in range(4)]

In [23]: [id(i) for i in x]
Out[23]: [164382060, 164364140, 164363628, 164381292] #different id(), i.e unique objects this time

Problems with a PHP shell script: "Could not open input file"

Windows Character Encoding Issue

I was having the same issue. I was editing files in PDT Eclipse on Windows and WinSCPing them over. I just copied and pasted the contents into a nano window, saved, and now they worked. Definitely some Windows character encoding issue, and not a matter of Shebangs or interpreter flags.

How to start an application using android ADB tools?

monkey --pct-syskeys 0 for development boards

Without this argument, the app won't open on a development board without keys / display:

adb shell monkey --pct-syskeys 0 -p com.cirosantilli.android_cheat.textviewbold 1

and fails with error:

SYS_KEYS has no physical keys but with factor 2.0%

Tested on HiKey960, Android O AOSP.

Learned from: https://github.com/ARM-software/lisa/pull/408

Also asked at: monkey test : If the Android system doesnt has physical keys ,what are the parameters need to be includeded in the command

Installing SciPy with pip

  1. install python-3.4.4
  2. scipy-0.15.1-win32-superpack-python3.4
  3. apply the following commend doc
py -m pip install --upgrade pip
py -m pip install numpy
py -m pip install matplotlib
py -m pip install scipy
py -m pip install scikit-learn

While loop in batch

set /a countfiles-=%countfiles%

This will set countfiles to 0. I think you want to decrease it by 1, so use this instead:

set /a countfiles-=1

I'm not sure if the for loop will work, better try something like this:

:loop
cscript /nologo c:\deletefile.vbs %BACKUPDIR%
set /a countfiles-=1
if %countfiles% GTR 21 goto loop

Video 100% width and height

use this css for height

height: calc(100vh) !important;

This will make the video to have 100% vertical height available.

Django values_list vs values

The values() method returns a QuerySet containing dictionaries:

<QuerySet [{'comment_id': 1}, {'comment_id': 2}]>

The values_list() method returns a QuerySet containing tuples:

<QuerySet [(1,), (2,)]>

If you are using values_list() with a single field, you can use flat=True to return a QuerySet of single values instead of 1-tuples:

<QuerySet [1, 2]>

How to view transaction logs in SQL Server 2008

You can't read the transaction log file easily because that's not properly documented. There are basically two ways to do this. Using undocumented or semi-documented database functions or using third-party tools.

Note: This only makes sense if your database is in full recovery mode.

SQL Functions:

DBCC LOG and fn_dblog - more details here and here.

Third-party tools:

Toad for SQL Server and ApexSQL Log.

You can also check out several other topics where this was discussed:

When should I use a table variable vs temporary table in sql server?

Your question shows you have succumbed to some of the common misconceptions surrounding table variables and temporary tables.

I have written quite an extensive answer on the DBA site looking at the differences between the two object types. This also addresses your question about disk vs memory (I didn't see any significant difference in behaviour between the two).

Regarding the question in the title though as to when to use a table variable vs a local temporary table you don't always have a choice. In functions, for example, it is only possible to use a table variable and if you need to write to the table in a child scope then only a #temp table will do (table-valued parameters allow readonly access).

Where you do have a choice some suggestions are below (though the most reliable method is to simply test both with your specific workload).

  1. If you need an index that cannot be created on a table variable then you will of course need a #temporary table. The details of this are version dependant however. For SQL Server 2012 and below the only indexes that could be created on table variables were those implicitly created through a UNIQUE or PRIMARY KEY constraint. SQL Server 2014 introduced inline index syntax for a subset of the options available in CREATE INDEX. This has been extended since to allow filtered index conditions. Indexes with INCLUDE-d columns or columnstore indexes are still not possible to create on table variables however.

  2. If you will be repeatedly adding and deleting large numbers of rows from the table then use a #temporary table. That supports TRUNCATE (which is more efficient than DELETE for large tables) and additionally subsequent inserts following a TRUNCATE can have better performance than those following a DELETE as illustrated here.

  3. If you will be deleting or updating a large number of rows then the temp table may well perform much better than a table variable - if it is able to use rowset sharing (see "Effects of rowset sharing" below for an example).
  4. If the optimal plan using the table will vary dependent on data then use a #temporary table. That supports creation of statistics which allows the plan to be dynamically recompiled according to the data (though for cached temporary tables in stored procedures the recompilation behaviour needs to be understood separately).
  5. If the optimal plan for the query using the table is unlikely to ever change then you may consider a table variable to skip the overhead of statistics creation and recompiles (would possibly require hints to fix the plan you want).
  6. If the source for the data inserted to the table is from a potentially expensive SELECT statement then consider that using a table variable will block the possibility of this using a parallel plan.
  7. If you need the data in the table to survive a rollback of an outer user transaction then use a table variable. A possible use case for this might be logging the progress of different steps in a long SQL batch.
  8. When using a #temp table within a user transaction locks can be held longer than for table variables (potentially until the end of transaction vs end of statement dependent on the type of lock and isolation level) and also it can prevent truncation of the tempdb transaction log until the user transaction ends. So this might favour the use of table variables.
  9. Within stored routines, both table variables and temporary tables can be cached. The metadata maintenance for cached table variables is less than that for #temporary tables. Bob Ward points out in his tempdb presentation that this can cause additional contention on system tables under conditions of high concurrency. Additionally, when dealing with small quantities of data this can make a measurable difference to performance.

Effects of rowset sharing

DECLARE @T TABLE(id INT PRIMARY KEY, Flag BIT);

CREATE TABLE #T (id INT PRIMARY KEY, Flag BIT);

INSERT INTO @T 
output inserted.* into #T
SELECT TOP 1000000 ROW_NUMBER() OVER (ORDER BY @@SPID), 0
FROM master..spt_values v1, master..spt_values v2

SET STATISTICS TIME ON

/*CPU time = 7016 ms,  elapsed time = 7860 ms.*/
UPDATE @T SET Flag=1;

/*CPU time = 6234 ms,  elapsed time = 7236 ms.*/
DELETE FROM @T

/* CPU time = 828 ms,  elapsed time = 1120 ms.*/
UPDATE #T SET Flag=1;

/*CPU time = 672 ms,  elapsed time = 980 ms.*/
DELETE FROM #T

DROP TABLE #T

Internet Access in Ubuntu on VirtualBox

I had the same problem.

Solved by sharing internet connection (on the hosting OS).

Network Connection Properties -> advanced -> Allow other users to connect...

How to write trycatch in R

Here goes a straightforward example:

# Do something, or tell me why it failed
my_update_function <- function(x){
    tryCatch(
        # This is what I want to do...
        {
        y = x * 2
        return(y)
        },
        # ... but if an error occurs, tell me what happened: 
        error=function(error_message) {
            message("This is my custom message.")
            message("And below is the error message from R:")
            message(error_message)
            return(NA)
        }
    )
}

If you also want to capture a "warning", just add warning= similar to the error= part.

How to get the real path of Java application at runtime?

It is better to save files into a sub-directory of user.home than wherever the app. might reside.

Sun went to considerable effort to ensure that applets and apps. launched using Java Web Start cannot determine the apps. real path. This change broke many apps. I would not be surprised if the changes are extended to other apps.

Generate random array of floats between a range

Why not use a list comprehension?

In Python 2

ran_floats = [random.uniform(low,high) for _ in xrange(size)]

In Python 3, range works like xrange(ref)

ran_floats = [random.uniform(low,high) for _ in range(size)]

How to add a right button to a UINavigationController?

There is a default system button for "Refresh":

- (void)viewDidLoad {
    [super viewDidLoad];

    UIBarButtonItem *refreshButton = [[[UIBarButtonItem alloc] 
                            initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh
                            target:self action:@selector(refreshClicked:)] autorelease];
    self.navigationItem.rightBarButtonItem = refreshButton;

}

- (IBAction)refreshClicked:(id)sender {

}

Set the space between Elements in Row Flutter

There are many ways of doing it, I'm listing a few here:

  1. Use SizedBox if you want to set some specific space

    Row(
      children: <Widget>[
        Text("1"),
        SizedBox(width: 50), // give it width
        Text("2"),
      ],
    )
    

    enter image description here


  1. Use Spacer if you want both to be as far apart as possible.

    Row(
      children: <Widget>[
        Text("1"),
        Spacer(), // use Spacer
        Text("2"),
      ],
    )
    

    enter image description here


  1. Use mainAxisAlignment according to your needs:

    Row(
      mainAxisAlignment: MainAxisAlignment.spaceEvenly, // use whichever suits your need
      children: <Widget>[
        Text("1"),
        Text("2"),
      ],
    )
    

    enter image description here


  1. Use Wrap instead of Row and give some spacing

    Wrap(
      spacing: 100, // set spacing here
      children: <Widget>[
        Text("1"),
        Text("2"),
      ],
    )
    

    enter image description here


  1. Use Wrap instead of Row and give it alignment

    Wrap(
      alignment: WrapAlignment.spaceAround, // set your alignment
      children: <Widget>[
        Text("1"),
        Text("2"),
      ],
    )
    

    enter image description here

Conda command is not recognized on Windows 10

When you install anaconda on windows now, it doesn't automatically add Python or Conda.

If you don’t know where your conda and/or python is, you type the following commands into your anaconda prompt

enter image description here

Next, you can add Python and Conda to your path by using the setx command in your command prompt. enter image description here

Next close that command prompt and open a new one. Congrats you can now use conda and python

Source: https://medium.com/@GalarnykMichael/install-python-on-windows-anaconda-c63c7c3d1444

npm install -g less does not work: EACCES: permission denied

For my mac environment

sudo chown -R $USER /usr/local/lib/node_modules

solve the issue

How to stop VBA code running?

Add another button called "CancelButton" that sets a flag, and then check for that flag.

If you have long loops in the "stuff" then check for it there too and exit if it's set. Use DoEvents inside long loops to ensure that the UI works.

Bool Cancel
Private Sub CancelButton_OnClick()
    Cancel=True
End Sub
...
Private Sub SomeVBASub
    Cancel=False
    DoStuff
    If Cancel Then Exit Sub
    DoAnotherStuff
    If Cancel Then Exit Sub
    AndFinallyDothis
End Sub

Android Min SDK Version vs. Target SDK Version

The comment posted by the OP to the question (basically stating that the targetSDK doesn't affect the compiling of an app) is entirely wrong! Sorry to be blunt.

In short, here is the purpose to declaring a different targetSDK from the minSDK: It means you are using features from a higher level SDK than your minimum, but you have ensured backwards compatibility. In other words, imagine that you want to use a feature that was only recently introduced, but that isn't critical to your application. You would then set the targetSDK to the version where this new feature was introduced and the minimum to something lower so that everyone could still use your app.

To give an example, let's say you're writing an app that makes extensive use of gesture detection. However, every command that can be recognised by a gesture can also be done by a button or from the menu. In this case, gestures are a 'cool extra' but aren't required. Therefore you would set the target sdk to 7 ("Eclair" when the GestureDetection library was introduced), and the minimumSDK to level 3 ("Cupcake") so that even people with really old phones could use your app. All you'd have to do is make sure that your app checked the version of Android it was running on before trying to use the gesture library, to avoid trying to use it if it didn't exist. (Admittedly this is a dated example since hardly anyone still has a v1.5 phone, but there was a time when maintaining compatibility with v1.5 was really important.)

To give another example, you could use this if you wanted to use a feature from Gingerbread or Honeycomb. Some people will get the updates soon, but many others, particularly with older hardware, might stay stuck with Eclair until they buy a new device. This would let you use some of the cool new features, but without excluding part of your possible market.

There is a really good article from the Android developer's blog about how to use this feature, and in particular, how to design the "check the feature exists before using it" code I mentioned above.

To the OP: I've written this mainly for the benefit of anyone who happens to stumble upon this question in the future, as I realise your question was asked a long time ago.

Which SchemaType in Mongoose is Best for Timestamp?

Mongoose now supports the timestamps in schema.

const item = new Schema(
  {
    id: {
      type: String,
      required: true,
    },
  { timestamps: true },
);

This will add the createdAt and updatedAt fields on each record create.

Timestamp interface has fields

  interface SchemaTimestampsConfig {
    createdAt?: boolean | string;
    updatedAt?: boolean | string;
    currentTime?: () => (Date | number);
  }

This would help us to choose which fields we want and overwrite the date format.

Separation of business logic and data access in django

It seems like you are asking about the difference between the data model and the domain model – the latter is where you can find the business logic and entities as perceived by your end user, the former is where you actually store your data.

Furthermore, I've interpreted the 3rd part of your question as: how to notice failure to keep these models separate.

These are two very different concepts and it's always hard to keep them separate. However, there are some common patterns and tools that can be used for this purpose.

About the Domain Model

The first thing you need to recognize is that your domain model is not really about data; it is about actions and questions such as "activate this user", "deactivate this user", "which users are currently activated?", and "what is this user's name?". In classical terms: it's about queries and commands.

Thinking in Commands

Let's start by looking at the commands in your example: "activate this user" and "deactivate this user". The nice thing about commands is that they can easily be expressed by small given-when-then scenario's:

given an inactive user
when the admin activates this user
then the user becomes active
and a confirmation e-mail is sent to the user
and an entry is added to the system log
(etc. etc.)

Such scenario's are useful to see how different parts of your infrastructure can be affected by a single command – in this case your database (some kind of 'active' flag), your mail server, your system log, etc.

Such scenario's also really help you in setting up a Test Driven Development environment.

And finally, thinking in commands really helps you create a task-oriented application. Your users will appreciate this :-)

Expressing Commands

Django provides two easy ways of expressing commands; they are both valid options and it is not unusual to mix the two approaches.

The service layer

The service module has already been described by @Hedde. Here you define a separate module and each command is represented as a function.

services.py

def activate_user(user_id):
    user = User.objects.get(pk=user_id)

    # set active flag
    user.active = True
    user.save()

    # mail user
    send_mail(...)

    # etc etc

Using forms

The other way is to use a Django Form for each command. I prefer this approach, because it combines multiple closely related aspects:

  • execution of the command (what does it do?)
  • validation of the command parameters (can it do this?)
  • presentation of the command (how can I do this?)

forms.py

class ActivateUserForm(forms.Form):

    user_id = IntegerField(widget = UsernameSelectWidget, verbose_name="Select a user to activate")
    # the username select widget is not a standard Django widget, I just made it up

    def clean_user_id(self):
        user_id = self.cleaned_data['user_id']
        if User.objects.get(pk=user_id).active:
            raise ValidationError("This user cannot be activated")
        # you can also check authorizations etc. 
        return user_id

    def execute(self):
        """
        This is not a standard method in the forms API; it is intended to replace the 
        'extract-data-from-form-in-view-and-do-stuff' pattern by a more testable pattern. 
        """
        user_id = self.cleaned_data['user_id']

        user = User.objects.get(pk=user_id)

        # set active flag
        user.active = True
        user.save()

        # mail user
        send_mail(...)

        # etc etc

Thinking in Queries

You example did not contain any queries, so I took the liberty of making up a few useful queries. I prefer to use the term "question", but queries is the classical terminology. Interesting queries are: "What is the name of this user?", "Can this user log in?", "Show me a list of deactivated users", and "What is the geographical distribution of deactivated users?"

Before embarking on answering these queries, you should always ask yourself this question, is this:

  • a presentational query just for my templates, and/or
  • a business logic query tied to executing my commands, and/or
  • a reporting query.

Presentational queries are merely made to improve the user interface. The answers to business logic queries directly affect the execution of your commands. Reporting queries are merely for analytical purposes and have looser time constraints. These categories are not mutually exclusive.

The other question is: "do I have complete control over the answers?" For example, when querying the user's name (in this context) we do not have any control over the outcome, because we rely on an external API.

Making Queries

The most basic query in Django is the use of the Manager object:

User.objects.filter(active=True)

Of course, this only works if the data is actually represented in your data model. This is not always the case. In those cases, you can consider the options below.

Custom tags and filters

The first alternative is useful for queries that are merely presentational: custom tags and template filters.

template.html

<h1>Welcome, {{ user|friendly_name }}</h1>

template_tags.py

@register.filter
def friendly_name(user):
    return remote_api.get_cached_name(user.id)

Query methods

If your query is not merely presentational, you could add queries to your services.py (if you are using that), or introduce a queries.py module:

queries.py

def inactive_users():
    return User.objects.filter(active=False)


def users_called_publysher():
    for user in User.objects.all():
        if remote_api.get_cached_name(user.id) == "publysher":
            yield user 

Proxy models

Proxy models are very useful in the context of business logic and reporting. You basically define an enhanced subset of your model. You can override a Manager’s base QuerySet by overriding the Manager.get_queryset() method.

models.py

class InactiveUserManager(models.Manager):
    def get_queryset(self):
        query_set = super(InactiveUserManager, self).get_queryset()
        return query_set.filter(active=False)

class InactiveUser(User):
    """
    >>> for user in InactiveUser.objects.all():
    …        assert user.active is False 
    """

    objects = InactiveUserManager()
    class Meta:
        proxy = True

Query models

For queries that are inherently complex, but are executed quite often, there is the possibility of query models. A query model is a form of denormalization where relevant data for a single query is stored in a separate model. The trick of course is to keep the denormalized model in sync with the primary model. Query models can only be used if changes are entirely under your control.

models.py

class InactiveUserDistribution(models.Model):
    country = CharField(max_length=200)
    inactive_user_count = IntegerField(default=0)

The first option is to update these models in your commands. This is very useful if these models are only changed by one or two commands.

forms.py

class ActivateUserForm(forms.Form):
    # see above
   
    def execute(self):
        # see above
        query_model = InactiveUserDistribution.objects.get_or_create(country=user.country)
        query_model.inactive_user_count -= 1
        query_model.save()

A better option would be to use custom signals. These signals are of course emitted by your commands. Signals have the advantage that you can keep multiple query models in sync with your original model. Furthermore, signal processing can be offloaded to background tasks, using Celery or similar frameworks.

signals.py

user_activated = Signal(providing_args = ['user'])
user_deactivated = Signal(providing_args = ['user'])

forms.py

class ActivateUserForm(forms.Form):
    # see above
   
    def execute(self):
        # see above
        user_activated.send_robust(sender=self, user=user)

models.py

class InactiveUserDistribution(models.Model):
    # see above

@receiver(user_activated)
def on_user_activated(sender, **kwargs):
        user = kwargs['user']
        query_model = InactiveUserDistribution.objects.get_or_create(country=user.country)
        query_model.inactive_user_count -= 1
        query_model.save()
    

Keeping it clean

When using this approach, it becomes ridiculously easy to determine if your code stays clean. Just follow these guidelines:

  • Does my model contain methods that do more than managing database state? You should extract a command.
  • Does my model contain properties that do not map to database fields? You should extract a query.
  • Does my model reference infrastructure that is not my database (such as mail)? You should extract a command.

The same goes for views (because views often suffer from the same problem).

  • Does my view actively manage database models? You should extract a command.

Some References

Django documentation: proxy models

Django documentation: signals

Architecture: Domain Driven Design

jQuery: Uncheck other checkbox on one checked

you could use class for all your checkboxes, and do:

$(".check_class").click(function() {
  $(".check_class").attr("checked", false); //uncheck all checkboxes
  $(this).attr("checked", true);  //check the clicked one
});

How to change workspace and build record Root Directory on Jenkins?

I figured it out. In order to save your Jenkins data on other drive you'll need to do the following:

Workspace Root Directory: E:\Jenkins\${ITEM_FULL_NAME}\workspace
Build Record Root Directory: E:\Jenkins\${ITEM_FULL_NAME}\builds

Change Directory

How to import popper.js?

I had the same problem. Tried different approches, but this one worked for me. Read the instruction from http://getbootstrap.com/.

Copy the CDN paths of Javascripts (Popper, jQuery and Bootstrap) in same manner (it is important) as given.

enter image description here

_x000D_
_x000D_
<head>_x000D_
//Path to jQuery_x000D_
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>_x000D_
_x000D_
////Path to Popper - it is for dropsdowns etc in bootstrap_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.3/umd/popper.min.js" integrity="sha384-vFJXuSJphROIrBnz7yo7oB41mKfc8JzQZiCq4NCceLEaO4IHwicKwpJf9c9IpFgh" crossorigin="anonymous"></script>_x000D_
_x000D_
//Path to bootsrap_x000D_
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/js/bootstrap.min.js" integrity="sha384-alpBpkh1PFOepccYVYDB4do5UnbKysX5WZXm3XxPqe5iKTfUKjNkCk9SaVuEZflJ" crossorigin="anonymous"></script>_x000D_
</head>
_x000D_
_x000D_
_x000D_

jQuery - checkbox enable/disable

Change your markup slightly:

_x000D_
_x000D_
$(function() {_x000D_
  enable_cb();_x000D_
  $("#group1").click(enable_cb);_x000D_
});_x000D_
_x000D_
function enable_cb() {_x000D_
  if (this.checked) {_x000D_
    $("input.group1").removeAttr("disabled");_x000D_
  } else {_x000D_
    $("input.group1").attr("disabled", true);_x000D_
  }_x000D_
}
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<form name="frmChkForm" id="frmChkForm">_x000D_
  <input type="checkbox" name="chkcc9" id="group1">Check Me <br>_x000D_
  <input type="checkbox" name="chk9[120]" class="group1"><br>_x000D_
  <input type="checkbox" name="chk9[140]" class="group1"><br>_x000D_
  <input type="checkbox" name="chk9[150]" class="group1"><br>_x000D_
</form>
_x000D_
_x000D_
_x000D_

You can do this using attribute selectors without introducing the ID and classes but it's slower and (imho) harder to read.

What is the difference between & vs @ and = in angularJS

AngularJS – Isolated Scopes – @ vs = vs &


Short examples with explanation are available at below link :

http://www.codeforeach.com/angularjs/angularjs-isolated-scopes-vs-vs

@ – one way binding

In directive:

scope : { nameValue : "@name" }

In view:

<my-widget name="{{nameFromParentScope}}"></my-widget>

= – two way binding

In directive:

scope : { nameValue : "=name" },
link : function(scope) {
  scope.name = "Changing the value here will get reflected in parent scope value";
}

In view:

<my-widget name="{{nameFromParentScope}}"></my-widget>

& – Function call

In directive :

scope : { nameChange : "&" }
link : function(scope) {
  scope.nameChange({newName:"NameFromIsolaltedScope"});
}

In view:

<my-widget nameChange="onNameChange(newName)"></my-widget>

How can I cast int to enum?

enter image description here

To convert a string to ENUM or int to ENUM constant we need to use Enum.Parse function. Here is a youtube video https://www.youtube.com/watch?v=4nhx4VwdRDk which actually demonstrate's with string and the same applies for int.

The code goes as shown below where "red" is the string and "MyColors" is the color ENUM which has the color constants.

MyColors EnumColors = (MyColors)Enum.Parse(typeof(MyColors), "Red");

How to write a SQL DELETE statement with a SELECT statement in the WHERE clause?

You need to identify the primary key in TableA in order to delete the correct record. The primary key may be a single column or a combination of several columns that uniquely identifies a row in the table. If there is no primary key, then the ROWID pseudo column may be used as the primary key.

DELETE FROM tableA
WHERE ROWID IN 
  ( SELECT q.ROWID
    FROM tableA q
      INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) 
    WHERE (LENGTH(q.memotext) NOT IN (8,9,10) OR q.memotext NOT LIKE '%/%/%')
      AND (u.FldFormat = 'Date'));

How can I make a horizontal ListView in Android?

I used Pauls (see his answer) Implementation of HorizontalListview and it works, thank you so much for sharing!

I slightly changed his HorizontalListView-Class (btw. Paul there is a typo in your classname, your classname is "HorizontialListView" instead of "HorizontalListView", the "i" is too much) to update child-views when selected.

UPDATE: My code that I posted here was wrong I suppose, as I ran into trouble with selection (i think it has to do with view recycling), I have to go back to the drawing board...

UPDATE 2: Ok Problem solved, I simply commented "removeNonVisibleItems(dx);" in "onLayout(..)", I guess this will hurt performance, but since I am using only very small Lists this is no Problem for me.

I basically used this tutorial here on developerlife and just replaced ListView with Pauls HorizontalListView, and made the changes to allow for "permanent" selection (a child that is clicked on changes its appearance, and when its clicked on again it changes it back).

I am a beginner, so probably many ugly things in the code, let me know if you need more details.

python-pandas and databases like mysql

MySQL example:

import MySQLdb as db
from pandas import DataFrame
from pandas.io.sql import frame_query

database = db.connect('localhost','username','password','database')
data     = frame_query("SELECT * FROM data", database)

Skip to next iteration in loop vba

Just do nothing once the criteria is met, otherwise do the processing you require and the For loop will go to the next item.

For i = 2 To 24
    Level = Cells(i, 4)
    Return = Cells(i, 5)

    If Return = 0 And Level = 0 Then
        'Do nothing
    Else
        'Do something
    End If
Next i

Or change the clause so it only processes if the conditions are met:

For i = 2 To 24
    Level = Cells(i, 4)
    Return = Cells(i, 5)

    If Return <> 0 Or Level <> 0 Then
        'Do something
    End If
Next i

What are the differences between if, else, and else if?

If and else if both are used to test the conditions.

I take case of If and else..

In the if case compiler check all cases Wether it is true or false. if no one block execute then else part will be executed.

in the case of else if compiler stop the flow of program when it got false value. it does not read whole program.So better performance we use else if.

But both have their importance according to situation

i take example of foor ordering menu if i use else if then it will suit well because user can check only one also. and it will give error so i use if here..

 StringBuilder result=new StringBuilder();  
            result.append("Selected Items:");  
            if(pizza.isChecked()){  
                result.append("\nPizza 100Rs");  
                totalamount+=100;  
            }  
            if(coffe.isChecked()){  
                result.append("\nCoffe 50Rs");  
                totalamount+=50;  
            }  
            if(burger.isChecked()){  
                result.append("\nBurger 120Rs");  
                totalamount+=120;  
            }  
            result.append("\nTotal: "+totalamount+"Rs");  
            //Displaying the message on the toast  
            Toast.makeText(getApplicationContext(), result.toString(), Toast.LENGTH_LONG).show();  
        }  

now else if case

if (time < 12) {
    greeting = "Good morning";
} else if (time < 22) {
    greeting = "Good day";
} else {
    greeting = "Good evening";
}

here only satisfy one condition.. and in case of if multiple conditions can be satisfied...

Custom toast on Android: a simple example

See link here. You find your solution. And try:

Creating a Custom Toast View

If a simple text message isn't enough, you can create a customized layout for your toast notification. To create a custom layout, define a View layout, in XML or in your application code, and pass the root View object to the setView (View) method.

For example, you can create the layout for the toast visible in the screenshot to the right with the following XML (saved as toast_layout.xml):

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
            android:id="@+id/toast_layout_root"
            android:orientation="horizontal"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:padding="10dp"
            android:background="#DAAA"
>

    <ImageView android:id="@+id/image"
               android:layout_width="wrap_content"
               android:layout_height="fill_parent"
               android:layout_marginRight="10dp"
    />

    <TextView android:id="@+id/text"
              android:layout_width="wrap_content"
              android:layout_height="fill_parent"
              android:textColor="#FFF"
    />
</LinearLayout>

Notice that the ID of the LinearLayout element is "toast_layout". You must use this ID to inflate the layout from the XML, as shown here:

 LayoutInflater inflater = getLayoutInflater();
 View layout = inflater.inflate(R.layout.toast_layout,
                                (ViewGroup) findViewById(R.id.toast_layout_root));

 ImageView image = (ImageView) layout.findViewById(R.id.image);
 image.setImageResource(R.drawable.android);
 TextView text = (TextView) layout.findViewById(R.id.text);
 text.setText("Hello! This is a custom toast!");

 Toast toast = new Toast(getApplicationContext());
 toast.setGravity(Gravity.CENTER_VERTICAL, 0, 0);
 toast.setDuration(Toast.LENGTH_LONG);
 toast.setView(layout);
 toast.show();

First, retrieve the LayoutInflater with getLayoutInflater() (or getSystemService()), and then inflate the layout from XML using inflate(int, ViewGroup). The first parameter is the layout resource ID and the second is the root View. You can use this inflated layout to find more View objects in the layout, so now capture and define the content for the ImageView and TextView elements. Finally, create a new Toast with Toast(Context) and set some properties of the toast, such as the gravity and duration. Then call setView(View) and pass it the inflated layout. You can now display the toast with your custom layout by calling show().

Note: Do not use the public constructor for a Toast unless you are going to define the layout with setView(View). If you do not have a custom layout to use, you must use makeText(Context, int, int) to create the Toast.

How to set value of input text using jQuery

this is for classes

$('.nameofdiv').val('we are developers');

for ids

$('#nameofdiv').val('we are developers');

now if u have an iput in a form u can use

$("#form li.name input.name_val").val('we are awsome developers');

How to use local docker images with Minikube?

Adding to to @Farhad 's answer based on this answer,

This are the steps to setup a local registry.

Setup in local machine

Setup hostname in local machine: edit /etc/hosts to add this line

docker.local 127.0.0.1

Now start a local registry (remove -d to run non-daemon mode) :

docker run -d -p 5000:5000 --restart=always --name registry registry:2

Now tag your image properly:

docker tag ubuntu docker.local:5000/ubuntu

Now push your image to local registry:

docker push docker.local:5000/ubuntu

Verify that image is pushed:

curl -X GET http://docker.local:5000/v2/ubuntu/tags/list

Setup in minikube

ssh into minikube with: minukube ssh

edit /etc/hosts to add this line

docker.local <your host machine's ip>

Verify access:

curl -X GET http://docker.local:5000/v2/ubuntu/tags/list

Now if you try to pull, yo might get an http access error.

Enable insecure access:

If you are always planning to use minkube with this local setup then create a minikube to use insecure registry by default (wont work on existing cluster).

minikube start --insecure-registry="docker.local:5000"

else follow below steps:

systemctl stop docker

edit the docker serice file: get path from systemctl status docker

it might be :

/etc/systemd/system/docker.service.d/10-machine.conf or /usr/lib/systemd/system/docker.service

append this text (replace 192.168.1.4 with your ip)

--insecure-registry docker.local:5000 --insecure-registry 192.168.1.4:5000

to this line

ExecStart=/usr/bin/docker daemon -H tcp://0.0.0.0:2376 -H unix:///var/run/docker.sock --tlsverify --tlscacert /etc/docker/ca.pem --tlscert /etc/docker/server.pem --tlskey /etc/docker/server-key.pem --label provider=virtualbox --insecure-registry 10.0.0.0/24

systemctl daemon-reload
systemctl start docker

try pulling:

docker pull docker.local:5000/ubuntu

Now change your yaml file to use local registry.

  containers:
    - name: ampl-django
      image: dockerhub/ubuntu

to

  containers:
    - name: ampl-django
      image: docker.local:5000/nymbleup

Don't use http in production, make the effort for securing things up.

"The breakpoint will not currently be hit. The source code is different from the original version." What does this mean?

If you have more than one projects in your solution, then make sure that the correct project is set as the StartUp Project. To set a particular project as the Startup Project of your solution, Right-click the project, choose Set As StartUp Project.

After I set my StartUp Project correctly, desired break-point was reached by the thread.

How to install Visual Studio 2015 on a different drive

I found these two links which might help you:

  1. https://www.reddit.com/r/csharp/comments/2agecc/why_must_visual_studio_be_installed_on_my_system/

  2. http://www.placona.co.uk/1196/dotnet/installing-visual-studio-on-a-different-drive/

Basically, at least a portion needs to be installed on a system drive. I'm not sure if your D:\ corresponds to some external drive or an actual system drive but the symlink solution might help.

Good luck

How to check if a variable is set in Bash?

To clearly answer OP's question of how to determine whether a variable is set, @Lionel's answer is correct:

if test "${name+x}"; then
    echo 'name is set'
else
    echo 'name is not set'
fi

This question already has a lot of answers, but none of them offered bona fide boolean expressions to clearly differentiate between variables values.

Here are some unambiguous expressions that I worked out:

+-----------------------+-------------+---------+------------+
| Expression in script  | name='fish' | name='' | unset name |
+-----------------------+-------------+---------+------------+
| test "$name"          | TRUE        | f       | f          |
| test -n "$name"       | TRUE        | f       | f          |
| test ! -z "$name"     | TRUE        | f       | f          |
| test ! "${name-x}"    | f           | TRUE    | f          |
| test ! "${name+x}"    | f           | f       | TRUE       |
+-----------------------+-------------+---------+------------+

By the way, these expressions are equivalent: test <expression> <=> [ <expression> ]

Other ambiguous expressions to be used with caution:

+----------------------+-------------+---------+------------+
| Expression in script | name='fish' | name='' | unset name |
+----------------------+-------------+---------+------------+
| test "${name+x}"     | TRUE        | TRUE    | f          |
| test "${name-x}"     | TRUE        | f       | TRUE       |
| test -z "$name"      | f           | TRUE    | TRUE       |
| test ! "$name"       | f           | TRUE    | TRUE       |
| test ! -n "$name"    | f           | TRUE    | TRUE       |
| test "$name" = ''    | f           | TRUE    | TRUE       |
+----------------------+-------------+---------+------------+

How to trim a string in SQL Server before 2017?

SELECT LTRIM(RTRIM(Replace(Replace(Replace(name,'   ',' '),CHAR(13), ' '),char(10), ' ')))
from author

How can you create multiple cursors in Visual Studio Code

Multi-word (and multi-line) cursors/selection in VS Code

Multi-word:

Windows / OS X:

  • Ctrl+Shift+L / ?+Shift+L selects all instances of the current highlighted word
  • Ctrl+D / ?+D selects the next instance... and the one after that... etc.

Multi-line:

For multi-line selection, Ctrl+Alt+Down / ?+Alt+Shift+Down will extend your selection or cursor position to the next line. Ctrl+Right / ?+Right will move to the end of each line, no matter how long. To escape the multi-line selection, hit Esc.

See the VS Code keybindings (OS sensitive)

Using DataContractSerializer to serialize, but can't deserialize back

I ended up doing the following and it works.

public static string Serialize(object obj)
{
    using (MemoryStream memoryStream = new MemoryStream())
    {
        DataContractSerializer serializer = new DataContractSerializer(obj.GetType());
        serializer.WriteObject(memoryStream, obj);
        return Encoding.UTF8.GetString(memoryStream.ToArray());
    }
}

public static object Deserialize(string xml, Type toType)
{
    using (MemoryStream memoryStream = new MemoryStream(Encoding.UTF8.GetBytes(xml)))
    {
        XmlDictionaryReader reader = XmlDictionaryReader.CreateTextReader(memoryStream, Encoding.UTF8, new XmlDictionaryReaderQuotas(), null);
        DataContractSerializer serializer = new DataContractSerializer(toType);
        return serializer.ReadObject(reader);
    }
}

It seems that the major problem was in the Serialize function when calling stream.GetBuffer(). Calling stream.ToArray() appears to work.

Read a HTML file into a string variable in memory

You can do it the simple way:

string pathToHTMLFile = @"C:\temp\someFile.html";
string htmlString = File.ReadAllText(pathToHTMLFile);

Or you could stream it in with FileStream/StreamReader:

using (FileStream fs = File.Open(pathToHTMLFile, FileMode.Open, FileAccess.ReadWrite))
{
    using (StreamReader sr = new StreamReader(fs))
    {
        htmlString = sr.ReadToEnd();
    }
}

This latter method allows you to open the file while still permitting others to perform Read/Write operations on the file. I can't imagine an HTML file being very big, but it has the added benefit of streaming the file instead of capturing it as one large chunk like the first method.

How to create empty folder in java?

Looks file you use the .mkdirs() method on a File object: http://www.roseindia.net/java/beginners/java-create-directory.shtml

// Create a directory; all non-existent ancestor directories are
// automatically created
success = (new File("../potentially/long/pathname/without/all/dirs")).mkdirs();
if (!success) {
    // Directory creation failed
}

How do I pass parameters to a jar file at the time of execution?

The JAVA Documentation says:

java [ options ] -jar file.jar [ argument ... ]

and

... Non-option arguments after the class name or JAR file name are passed to the main function...

Maybe you have to put the arguments in single quotes.

How can you have SharePoint Link Lists default to opening in a new window?

It is not possible with the default Link List web part, but there are resources describing how to extend Sharepoint server-side to add this functionality.

Share Point Links Open in New Window
Changing Link Lists in Sharepoint 2007

JavaScript alert box with timer

setTimeout( function ( ) { alert( "moo" ); }, 10000 ); //displays msg in 10 seconds

Apply style ONLY on IE

It really depends on the IE versions ... I found this excellent resource that is up to date from IE6-10:

CSS hack for Internet Explorer 6

It is called the Star HTML Hack and looks as follows:

  • html .color {color: #F00;} This hack uses fully valid CSS.

CSS hack for Internet Explorer 7

It is called the Star Plus Hack.

*:first-child+html .color {color: #F00;} Or a shorter version:

*+html .color {color: #F00;} Like the star HTML hack, this uses valid CSS.

CSS hack for Internet Explorer 8

@media \0screen { .color {color: #F00;} } This hacks does not use valid CSS.

CSS hack for Internet Explorer 9

:root .color {color: #F00\9;} This hacks also does not use valid CSS.

Added 2013.02.04: Unfortunately IE10 understands this hack.

CSS hack for Internet Explorer 10

@media screen and (-ms-high-contrast: active), (-ms-high-contrast: none) { .color {color: #F00;} } This hacks also does not use valid CSS.

What's the UIScrollView contentInset property for?

While jball's answer is an excellent description of content insets, it doesn't answer the question of when to use it. I'll borrow from his diagrams:

  _|?_cW_?_|_?_
   |       | 
---------------
   |content| ?
 ? |content| contentInset.top
cH |content|
 ? |content| contentInset.bottom
   |content| ?
---------------
   |content|    
-------------?-

That's what you get when you do it, but the usefulness of it only shows when you scroll:

  _|?_cW_?_|_?_
   |content| ? content is still visible
---------------
   |content| ?
 ? |content| contentInset.top
cH |content|
 ? |content| contentInset.bottom
   |content| ?
---------------
  _|_______|___ 
             ?

That top row of content will still be visible because it's still inside the frame of the scroll view. One way to think of the top offset is "how much to shift the content down the scroll view when we're scrolled all the way to the top"

To see a place where this is actually used, look at the build-in Photos app on the iphone. The Navigation bar and status bar are transparent, and the contents of the scroll view are visible underneath. That's because the scroll view's frame extends out that far. But if it wasn't for the content inset, you would never be able to have the top of the content clear that transparent navigation bar when you go all the way to the top.

Determine SQL Server Database Size

Common Query To Check Database Size in SQL Server that supports both Azure and On-Premises-

Method 1 – Using ‘sys.database_files’ System View

SELECT
    DB_NAME() AS [database_name],
    CONCAT(CAST(SUM(
        CAST( (size * 8.0/1024) AS DECIMAL(15,2) )
    ) AS VARCHAR(20)),' MB') AS [database_size]
FROM sys.database_files;

Method 2 – Using ‘sp_spaceused’ System Stored Procedure

EXEC sp_spaceused ;

ssh: Could not resolve hostname [hostname]: nodename nor servname provided, or not known

I had the same problem: The address shown in Preferences -> Sharing -> Remote Login didn't work and I got a '... nodename nor servname provided, or not known'. However, when I manually edited the settings (in Preferences -> Sharing -> Remote Login -> edit) and enabled "Use dynamic global hostname", it suddenly worked.

enter image description here

enter image description here

How to Concatenate Numbers and Strings to Format Numbers in T-SQL?

select 'abcd' + ltrim(str(1)) + ltrim(str(2))

How to find out "The most popular repositories" on Github?

Ranking by stars or forks is not working. Each promoted or created by a famous company repository is popular at the beginning. Also it is possible to have a number of them which are in trend right now (publications, marketing, events). It doesn't mean that those repositories are useful/popular.

The gitmostwanted.com project (repo at github) analyses GH Archive data in order to highlight the most interesting repositories and exclude others. Just compare the results with mentioned resources.

Check if a varchar is a number (TSQL)

DECLARE @A nvarchar(100) = '12'
IF(ISNUMERIC(@A) = 1)
BEGIN
    PRINT 'YES NUMERIC'
END

How to convert HTML to PDF using iText

This links might be helpful to convert.

https://code.google.com/p/flying-saucer/

https://today.java.net/pub/a/today/2007/06/26/generating-pdfs-with-flying-saucer-and-itext.html

If it is a college Project, you can even go for these, http://pd4ml.com/examples.htm

Example is given to convert HTML to PDF

Using LINQ to remove elements from a List<T>

Simple solution:

static void Main()
{
    List<string> myList = new List<string> { "Jason", "Bob", "Frank", "Bob" };
    myList.RemoveAll(x => x == "Bob");

    foreach (string s in myList)
    {
        //
    }
}

How to execute a query in ms-access in VBA code?

Take a look at this tutorial for how to use SQL inside VBA:

http://www.ehow.com/how_7148832_access-vba-query-results.html

For a query that won't return results, use (reference here):

DoCmd.RunSQL

For one that will, use (reference here):

Dim dBase As Database
dBase.OpenRecordset

How to rollback just one step using rake db:migrate

  try {
        $result=DB::table('users')->whereExists(function ($Query){
            $Query->where('id','<','14162756');
            $Query->whereBetween('password',[14162756,48384486]);
            $Query->whereIn('id',[3,8,12]);
        });
    }catch (\Exception $error){
        Log::error($error);
        DB::rollBack(1);
        return redirect()->route('bye');
    }

Live-stream video from one android phone to another over WiFi

I did work on something like this once, but sending a video and playing it in real time is a really complex thing. I suggest you work with PNG's only. In my implementation What i did was capture PNGs using the host camera and then sending them over the network to the client, Which will display the image as soon as received and request the next image from the host. Since you are on wifi that communication will be fast enough to get around 8-10 images per-second(approximation only, i worked on Bluetooth). So this will look like a continuous video but with much less effort. For communication you may use UDP sockets(Faster and less complex) or DLNA (Not sure how that works).

Confirmation before closing of tab/browser

The shortest solution for the year 2020 (for those happy people who don't need to support IE)

Tested in Chrome, Firefox, Safari.

function onBeforeUnload(e) {
    if (thereAreUnsavedChanges()) {
        e.preventDefault();
        e.returnValue = '';
        return;
    }

    delete e['returnValue'];
}

window.addEventListener('beforeunload', onBeforeUnload);

Actually no one modern browser (Chrome, Firefox, Safari) displays the "return value" as a question to user. Instead they show their own confirmation text (it depends on browser). But we still need to return some (even empty) string to trigger that confirmation on Chrome.

More explanations see on MDN here and here.

django MultiValueDictKeyError error, how do I deal with it

You get that because you're trying to get a key from a dictionary when it's not there. You need to test if it is in there first.

try:

is_private = 'is_private' in request.POST

or

is_private = 'is_private' in request.POST and request.POST['is_private']

depending on the values you're using.

Does Python have a string 'contains' substring method?

You can use regular expressions to get the occurrences:

>>> import re
>>> print(re.findall(r'( |t)', to_search_in)) # searches for t or space
['t', ' ', 't', ' ', ' ']

Angularjs - simple form submit

Sending data to some service page.

<form class="form-horizontal" role="form" ng-submit="submit_form()">
    <input type="text" name="user_id" ng-model = "formAdata.user_id">
    <input type="text" id="name" name="name" ng-model = "formAdata.name">
</form>

$scope.submit_form = function()
            {
                $http({
                        url: "http://localhost/services/test.php",
                        method: "POST",
                        headers: {'Content-Type': 'application/x-www-form-urlencoded'},
                        data: $.param($scope.formAdata)
                    }).success(function(data, status, headers, config) {
                        $scope.status = status;
                    }).error(function(data, status, headers, config) {
                        $scope.status = status;
                    });
            }

How many bytes in a JavaScript string?

I'm working with an embedded version of the V8 Engine. I've tested a single string. Pushing each step 1000 characters. UTF-8.

First test with single byte (8bit, ANSI) Character "A" (hex: 41). Second test with two byte character (16bit) "O" (hex: CE A9) and the third test with three byte character (24bit) "?" (hex: E2 98 BA).

In all three cases the device prints out of memory at 888 000 characters and using ca. 26 348 kb in RAM.

Result: The characters are not dynamically stored. And not with only 16bit. - Ok, perhaps only for my case (Embedded 128 MB RAM Device, V8 Engine C++/QT) - The character encoding has nothing to do with the size in ram of the javascript engine. E.g. encodingURI, etc. is only useful for highlevel data transmission and storage.

Embedded or not, fact is that the characters are not only stored in 16bit. Unfortunally I've no 100% answer, what Javascript do at low level area. Btw. I've tested the same (first test above) with an array of character "A". Pushed 1000 items every step. (Exactly the same test. Just replaced string to array) And the system bringt out of memory (wanted) after 10 416 KB using and array length of 1 337 000. So, the javascript engine is not simple restricted. It's a kind more complex.

Return the most recent record from ElasticSearch index

For information purpose, _timestamp is now deprecated since 2.0.0-beta2. Use date type in your mapping.

A simple date mapping JSON from date datatype doc:

{
  "mappings": {
     "my_type": {
        "properties": {
          "date": {
          "type": "date" 
        }
      }
    }
  }
}

You can also add a format field in date:

{
  "mappings": {
    "my_type": {
      "properties": {
        "date": {
          "type":   "date",
          "format": "yyy-MM-dd HH:mm:ss||yyyy-MM-dd||epoch_millis"
        }
      }
    }
  }
}

addEventListener vs onclick

The difference you could see if you had another couple of functions:

var h = document.getElementById('a');
h.onclick = doThing_1;
h.onclick = doThing_2;

h.addEventListener('click', doThing_3);
h.addEventListener('click', doThing_4);

Functions 2, 3 and 4 work, but 1 does not. This is because addEventListener does not overwrite existing event handlers, whereas onclick overrides any existing onclick = fn event handlers.

The other significant difference, of course, is that onclick will always work, whereas addEventListener does not work in Internet Explorer before version 9. You can use the analogous attachEvent (which has slightly different syntax) in IE <9.

How to set a value for a span using jQuery

Syntax:

$(selector).text() returns the text content.

$(selector).text(content) sets the text content.

$(selector).text(function(index, curContent)) sets text content using a function.

kaynak: https://www.geeksforgeeks.org/jquery-change-the-text-of-a-span-element/

Using :: in C++

look at it is informative [Qualified identifiers

A qualified id-expression is an unqualified id-expression prepended by a scope resolution operator ::, and optionally, a sequence of enumeration, (since C++11)class or namespace names or decltype expressions (since C++11) separated by scope resolution operators. For example, the expression std::string::npos is an expression that names the static member npos in the class string in namespace std. The expression ::tolower names the function tolower in the global namespace. The expression ::std::cout names the global variable cout in namespace std, which is a top-level namespace. The expression boost::signals2::connection names the type connection declared in namespace signals2, which is declared in namespace boost.

The keyword template may appear in qualified identifiers as necessary to disambiguate dependent template names]1

How to build splash screen in windows forms application?

First, create your splash screen as a borderless, immovable form with your image on it, set to initially display at the center of the screen, colored the way you want. All of this can be set from within the designer; specifically, you want to:

  • Set the form's ControlBox, MaximizeBox, MinimizeBox and ShowIcon properties to "False"
  • Set the StartPosition property to "CenterScreen"
  • Set the FormBorderStyle property to "None"
  • Set the form's MinimumSize and MaximumSize to be the same as its initial Size.

Then, you need to decide where to show it and where to dismiss it. These two tasks need to occur on opposite sides of the main startup logic of your program. This could be in your application's main() routine, or possibly in your main application form's Load handler; wherever you're creating large expensive objects, reading settings from the hard drive, and generally taking a long time to do stuff behind the scenes before the main application screen displays.

Then, all you have to do is create an instance of your form, Show() it, and keep a reference to it while you do your startup initialization. Once your main form has loaded, Close() it.

If your splash screen will have an animated image on it, the window will need to be "double-buffered" as well, and you will need to be absolutely sure that all initialization logic happens outside the GUI thread (meaning you cannot have your main loading logic in the mainform's Load handler; you'll have to create a BackgroundWorker or some other threaded routine.

IIs Error: Application Codebehind=“Global.asax.cs” Inherits=“nadeem.MvcApplication”

Make sure the Inherits is pointing to the right namespace of the class because when you create an MVC project under a solution the Inherits value will miss the project name. Therefore you need to fill the gap(project name) manually.

<br><br><%@ Application Codebehind="Global.asax.cs" Inherits="solutionName.projectName.MvcApplication" Language="C#" %>

Convert String to Type in C#

Try:

Type type = Type.GetType(inputString); //target type
object o = Activator.CreateInstance(type); // an instance of target type
YourType your = (YourType)o;

Jon Skeet is right as usually :)

Update: You can specify assembly containing target type in various ways, as Jon mentioned, or:

YourType your = (YourType)Activator.CreateInstance("AssemblyName", "NameSpace.MyClass");

What is the difference between localStorage, sessionStorage, session and cookies?

  1. LocalStorage

    Pros:

    1. Web storage can be viewed simplistically as an improvement on cookies, providing much greater storage capacity. If you look at the Mozilla source code we can see that 5120KB (5MB which equals 2.5 Million chars on Chrome) is the default storage size for an entire domain. This gives you considerably more space to work with than a typical 4KB cookie.
    2. The data is not sent back to the server for every HTTP request (HTML, images, JavaScript, CSS, etc) - reducing the amount of traffic between client and server.
    3. The data stored in localStorage persists until explicitly deleted. Changes made are saved and available for all current and future visits to the site.

    Cons:

    1. It works on same-origin policy. So, data stored will only be available on the same origin.
  2. Cookies

    Pros:

    1. Compared to others, there's nothing AFAIK.

    Cons:

    1. The 4K limit is for the entire cookie, including name, value, expiry date etc. To support most browsers, keep the name under 4000 bytes, and the overall cookie size under 4093 bytes.
    2. The data is sent back to the server for every HTTP request (HTML, images, JavaScript, CSS, etc) - increasing the amount of traffic between client and server.

      Typically, the following are allowed:

      • 300 cookies in total
      • 4096 bytes per cookie
      • 20 cookies per domain
      • 81920 bytes per domain(Given 20 cookies of max size 4096 = 81920 bytes.)
  3. sessionStorage

    Pros:

    1. It is similar to localStorage.
    2. The data is not persistent i.e. data is only available per window (or tab in browsers like Chrome and Firefox). Data is only available during the page session. Changes made are saved and available for the current page, as well as future visits to the site on the same window. Once the window is closed, the storage is deleted.

    Cons:

    1. The data is available only inside the window/tab in which it was set.
    2. Like localStorage, it works on same-origin policy. So, data stored will only be available on the same origin.

Checkout across-tabs - how to facilitate easy communication between cross-origin browser tabs.

Creating Scheduled Tasks

This works for me https://www.nuget.org/packages/ASquare.WindowsTaskScheduler/

It is nicely designed Fluent API.

//This will create Daily trigger to run every 10 minutes for a duration of 18 hours
SchedulerResponse response = WindowTaskScheduler
    .Configure()
    .CreateTask("TaskName", "C:\\Test.bat")
    .RunDaily()
    .RunEveryXMinutes(10)
    .RunDurationFor(new TimeSpan(18, 0, 0))
    .SetStartDate(new DateTime(2015, 8, 8))
    .SetStartTime(new TimeSpan(8, 0, 0))
    .Execute();

Implements vs extends: When to use? What's the difference?

As shown in the figure given below, a class extends another class, an interface extends another interface but a class implements an interface. enter image description here

For more details

Multiple parameters in a List. How to create without a class?

Another solution create generic list of anonymous type.

 var list = new[]
 { 
    new { Number = 10, Name = "Smith" },
    new { Number = 10, Name = "John" } 
 }.ToList();

 foreach (var item in list)
 {
    Console.WriteLine(item.Name);
 }

This also gives you intellisense support, I think in some situations its better than Tuple and Dictionary.

make html text input field grow as I type?

Here's a method that worked for me. When you type into the field, it puts that text into the hidden span, then gets its new width and applies it to the input field. It grows and shrinks with your input, with a safeguard against the input virtually disappearing when you erase all input. Tested in Chrome. (EDIT: works in Safari, Firefox and Edge at the time of this edit)

_x000D_
_x000D_
function travel_keyup(e)_x000D_
{_x000D_
    if (e.target.value.length == 0) return;_x000D_
    var oSpan=document.querySelector('#menu-enter-travel span');_x000D_
    oSpan.textContent=e.target.value;_x000D_
    match_span(e.target, oSpan);_x000D_
}_x000D_
function travel_keydown(e)_x000D_
{_x000D_
    if (e.key.length == 1)_x000D_
    {_x000D_
        if (e.target.maxLength == e.target.value.length) return;_x000D_
        var oSpan=document.querySelector('#menu-enter-travel span');_x000D_
        oSpan.textContent=e.target.value + '' + e.key;_x000D_
        match_span(e.target, oSpan);_x000D_
    }_x000D_
}_x000D_
function match_span(oInput, oSpan)_x000D_
{_x000D_
    oInput.style.width=oSpan.getBoundingClientRect().width + 'px';_x000D_
}_x000D_
_x000D_
window.addEventListener('load', function()_x000D_
{_x000D_
    var oInput=document.querySelector('#menu-enter-travel input');_x000D_
    oInput.addEventListener('keyup', travel_keyup);_x000D_
    oInput.addEventListener('keydown', travel_keydown);_x000D_
_x000D_
    match_span(oInput, document.querySelector('#menu-enter-travel span'));_x000D_
});
_x000D_
#menu-enter-travel input_x000D_
{_x000D_
 width: 8px;_x000D_
}_x000D_
#menu-enter-travel span_x000D_
{_x000D_
 visibility: hidden;_x000D_
    position: absolute;_x000D_
    top: 0px;_x000D_
    left: 0px;_x000D_
}
_x000D_
<div id="menu-enter-travel">_x000D_
<input type="text" pattern="^[0-9]{1,4}$" maxlength="4">KM_x000D_
<span>9</span>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to copy multiple files in one layer using a Dockerfile?

COPY <all> <the> <things> <last-arg-is-destination>

But here is an important excerpt from the docs:

If you have multiple Dockerfile steps that use different files from your context, COPY them individually, rather than all at once. This ensures that each step’s build cache is only invalidated (forcing the step to be re-run) if the specifically required files change.

https://docs.docker.com/develop/develop-images/dockerfile_best-practices/#add-or-copy

How to pass a value to razor variable from javascript variable?

Razor View Server Side variable can be read to Client Side JavaScript using @ While and JavaScript client side variable can read to Razor View using @:

Only mkdir if it does not exist

Use mkdir's -p option, but note that it has another effect as well.

 -p      Create intermediate directories as required.  If this option is not specified, the full path prefix of each oper-
         and must already exist.  On the other hand, with this option specified, no error will be reported if a directory
         given as an operand already exists.  Intermediate directories are created with permission bits of rwxrwxrwx
         (0777) as modified by the current umask, plus write and search permission for the owner.

How to sort a Ruby Hash by number value?

Since value is the last entry, you can do:

metrics.sort_by(&:last)

(HTML) Download a PDF file instead of opening them in browser when clicked

This is only possible with setting a http response header by the server side code. Namely;

Content-Disposition: attachment; filename=fname.ext

PostgreSQL: insert from another table

Very late answer, but I think my answer is more straight forward for specific use cases where users want to simply insert (copy) data from table A into table B:

INSERT INTO table_b (col1, col2, col3, col4, col5, col6)
SELECT col1, 'str_val', int_val, col4, col5, col6
FROM table_a

Print array elements on separate lines in Bash?

I tried the answers here in a giant for...if loop, but didn't get any joy - so I did it like this, maybe messy but did the job:

 # EXP_LIST2 is iterated    
 # imagine a for loop
     EXP_LIST="List item"    
     EXP_LIST2="$EXP_LIST2 \n $EXP_LIST"
 done 
 echo -e $EXP_LIST2

although that added a space to the list, which is fine - I wanted it indented a bit. Also presume the "\n" could be printed in the original $EP_LIST.

How to show math equations in general github's markdown(not github's blog)

I used the following in the head of mark down file

<script type="text/javascript" async
src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.2/MathJax.js? 
config=TeX-MML-AM_CHTML"
</script>

Then typed the following mathjax statement
$$x_{1,2} = \frac{-b \pm \sqrt{b^2-4ac}}{2b}.$$
It worked for me

Flutter: how to make a TextField with HintText but no Underline?

I found no other answer gives a border radius, you can simply do it like this, no nested Container

  TextField(
    decoration: InputDecoration(
      border: OutlineInputBorder(
        borderSide: BorderSide.none,
        borderRadius: BorderRadius.circular(20),
      ),
    ),
  );

Get loop counter/index using for…of syntax in JavaScript

In ES6, it is good to use for - of loop. You can get index in for of like this

for (let [index, val] of array.entries()) {
        // your code goes here    
}

Note that Array.entries() returns an iterator, which is what allows it to work in the for-of loop; don't confuse this with Object.entries(), which returns an array of key-value pairs.

How to get current user in asp.net core

I got my solution

var claim = HttpContext.User.CurrentUserID();

public static class XYZ
{
    public static int CurrentUserID(this ClaimsPrincipal claim)
    {
        var userID = claimsPrincipal.Claims.ToList().Find(r => r.Type == 
         "UserID").Value;
        return Convert.ToInt32(userID);
    }
    public static string CurrentUserRole(this ClaimsPrincipal claim)
    {
        var role = claimsPrincipal.Claims.ToList().Find(r => r.Type == 
        "Role").Value;
        return role;
    }
}

how to align text vertically center in android

Try to put android:gravity="center_vertical|right" inside parent LinearLayout else as you are inside RelativeLayout you can put android:layout_centerInParent="true" inside your scrollView.

How to log a method's execution time exactly in milliseconds?

I know this is an old one but even I found myself wandering past it again, so I thought I'd submit my own option here.

Best bet is to check out my blog post on this: Timing things in Objective-C: A stopwatch

Basically, I wrote a class that does stop watching in a very basic way but is encapsulated so that you only need to do the following:

[MMStopwatchARC start:@"My Timer"];
// your work here ...
[MMStopwatchARC stop:@"My Timer"];

And you end up with:

MyApp[4090:15203]  -> Stopwatch: [My Timer] runtime: [0.029]

in the log...

Again, check out my post for a little more or download it here: MMStopwatch.zip

How can I add an ampersand for a value in a ASP.net/C# app config file value

Have you tried this?

<appSettings>  
  <add key="myurl" value="http://www.myurl.com?&amp;cid=&amp;sid="/>
<appSettings>

Invert colors of an image in CSS or JavaScript

Can be done in major new broswers using the code below

.img {
    -webkit-filter:invert(100%);
     filter:progid:DXImageTransform.Microsoft.BasicImage(invert='1');
}

However, if you want it to work across all browsers you need to use Javascript. Something like this gist will do the job.

How to check if a column exists before adding it to an existing table in PL/SQL?

All the metadata about the columns in Oracle Database is accessible using one of the following views.

user_tab_cols; -- For all tables owned by the user

all_tab_cols ; -- For all tables accessible to the user

dba_tab_cols; -- For all tables in the Database.

So, if you are looking for a column like ADD_TMS in SCOTT.EMP Table and add the column only if it does not exist, the PL/SQL Code would be along these lines..

DECLARE
  v_column_exists number := 0;  
BEGIN
  Select count(*) into v_column_exists
    from user_tab_cols
    where upper(column_name) = 'ADD_TMS'
      and upper(table_name) = 'EMP';
      --and owner = 'SCOTT --*might be required if you are using all/dba views

  if (v_column_exists = 0) then
      execute immediate 'alter table emp add (ADD_TMS date)';
  end if;
end;
/

If you are planning to run this as a script (not part of a procedure), the easiest way would be to include the alter command in the script and see the errors at the end of the script, assuming you have no Begin-End for the script..

If you have file1.sql

alter table t1 add col1 date;
alter table t1 add col2 date;
alter table t1 add col3 date;

And col2 is present,when the script is run, the other two columns would be added to the table and the log would show the error saying "col2" already exists, so you should be ok.

Wrap text in <td> tag

It's possible that this might work, but it might prove to be a bit of a nuisance at some point in the future (if not immediately).

<style> 
tbody td span {display: inline-block;
               width: 10em; /* this is the nuisance part, as you'll have to define a particular width, and I assume -without testing- that any percent widths would be relative to the containing `<td>`, not the `<tr>` or `<table>` */
               overflow: hidden; 
               white-space: nowrap; }

</style>

...

<table>

<thead>...</thead>
<tfoot>...</tfoot>

<tbody>

<tr>

<td><span title="some text">some text</span></td> <td><span title="some more text">some more text</span></td> <td><span title="yet more text">yet more text</span></td>

</tr>

</tbody>

</table>

The rationale for the span is that, as pointed out by others, a <td> will typically expand to accommodate the content, whereas a <span> can be given -and expected to keep- a set width; the overflow: hidden is intended to, but might not, hide what would otherwise cause the <td> to expand.

I'd recommend using the title property of the span to show the text that's present (or clipped) in the visual cell, so that the text's still available (and if you don't want/need people to see it, then why have it in the first place, I guess...).

Also, if you define a width for the td {...} the td will expand (or potentially contract, but I doubt it) to fill its implied width (as I see it this seems to be table-width/number-of-cells), a specified table-width doesn't seem to create the same issue.

The downside is additional markup used for presentation.

How do I get the backtrace for all the threads in GDB?

Is there a command that does?

thread apply all where

Jquery If radio button is checked

jQuery('input[name="inputName"]:checked').val()

Prevent textbox autofill with previously entered values

By making AutoCompleteType="Disabled",

    <asp:TextBox runat="server" ID="txt_userid" AutoCompleteType="Disabled"></asp:TextBox>  

By setting autocomplete="off",

    <asp:TextBox runat="server" ID="txt_userid" autocomplete="off"></asp:TextBox>  

By Setting Form autocomplete="off",

    <form id="form1" runat="server" autocomplete="off">  
    //your content  
    </form>  

By using code in .cs page,

    protected void Page_Load(object sender, EventArgs e)   
    {  
        if (!Page.IsPostBack)  
        {  
            txt_userid.Attributes.Add("autocomplete", "off");  
        }  
    }  

By Using Jquery

    <head runat = "server" >  
        < title > < /title> < script src = "Scripts/jquery-1.6.4.min.js" > < /script> < script type = "text/javascript" >  
        $(document).ready(function()  
        {  
            $('#txt_userid').attr('autocomplete', 'off');  
        });  
    //document.getElementById("txt_userid").autocomplete = "off"  
    < /script>  

and here is my textbox in ,

    <asp:TextBox runat="server" ID="txt_userid" ></asp:TextBox>  

By Setting textbox attribute in code,

    protected void Page_Load(object sender, EventArgs e)   
    {  
        if (!Page.IsPostBack)  
        {  
            txt_userid.Attributes.Add("autocomplete", "off");  
        }  
    } 

Return value using String result=Command.ExecuteScalar() error occurs when result returns null

Value is not null, but DBNull.Value.

object value = cmd.ExecuteScalar();
if(value == DBNull.Value)

'str' object has no attribute 'decode'. Python 3 error?

For Python3

html = """\\u003Cdiv id=\\u0022contenedor\\u0022\\u003E \\u003Ch2 class=\\u0022text-left m-b-2\\u0022\\u003EInformaci\\u00f3n del veh\\u00edculo de patente AA345AA\\u003C\\/h2\\u003E\\n\\n\\n\\n \\u003Cdiv class=\\u0022panel panel-default panel-disabled m-b-2\\u0022\\u003E\\n \\u003Cdiv class=\\u0022panel-body\\u0022\\u003E\\n \\u003Ch2 class=\\u0022table_title m-b-2\\u0022\\u003EInformaci\\u00f3n del Registro Automotor\\u003C\\/h2\\u003E\\n \\u003Cdiv class=\\u0022col-md-6\\u0022\\u003E\\n \\u003Clabel class=\\u0022control-label\\u0022\\u003ERegistro Seccional\\u003C\\/label\\u003E\\n \\u003Cp\\u003ESAN MIGUEL N\\u00b0 1\\u003C\\/p\\u003E\\n \\u003Clabel class=\\u0022control-label\\u0022\\u003EDirecci\\u00f3n\\u003C\\/label\\u003E\\n \\u003Cp\\u003EMAESTRO ANGEL D\\u0027ELIA 766\\u003C\\/p\\u003E\\n \\u003Clabel class=\\u0022control-label\\u0022\\u003EPiso\\u003C\\/label\\u003E\\n \\u003Cp\\u003EPB\\u003C\\/p\\u003E\\n \\u003Clabel class=\\u0022control-label\\u0022\\u003EDepartamento\\u003C\\/label\\u003E\\n \\u003Cp\\u003E-\\u003C\\/p\\u003E\\n \\u003Clabel class=\\u0022control-label\\u0022\\u003EC\\u00f3digo postal\\u003C\\/label\\u003E\\n \\u003Cp\\u003E1663\\u003C\\/p\\u003E\\n \\u003C\\/div\\u003E\\n \\u003Cdiv class=\\u0022col-md-6\\u0022\\u003E\\n \\u003Clabel class=\\u0022control-label\\u0022\\u003ELocalidad\\u003C\\/label\\u003E\\n \\u003Cp\\u003ESAN MIGUEL\\u003C\\/p\\u003E\\n \\u003Clabel class=\\u0022control-label\\u0022\\u003EProvincia\\u003C\\/label\\u003E\\n \\u003Cp\\u003EBUENOS AIRES\\u003C\\/p\\u003E\\n \\u003Clabel class=\\u0022control-label\\u0022\\u003ETel\\u00e9fono\\u003C\\/label\\u003E\\n \\u003Cp\\u003E(11)46646647\\u003C\\/p\\u003E\\n \\u003Clabel class=\\u0022control-label\\u0022\\u003EHorario\\u003C\\/label\\u003E\\n \\u003Cp\\u003E08:30 a 12:30\\u003C\\/p\\u003E\\n \\u003C\\/div\\u003E\\n \\u003C\\/div\\u003E\\n\\u003C\\/div\\u003E \\n\\n\\u003Cp class=\\u0022text-center m-t-3 m-b-1 hidden-print\\u0022\\u003E\\n \\u003Ca href=\\u0022javascript:window.print();\\u0022 class=\\u0022btn btn-default\\u0022\\u003EImprim\\u00ed la consulta\\u003C\\/a\\u003E \\u0026nbsp; \\u0026nbsp;\\n \\u003Ca href=\\u0022\\u0022 class=\\u0022btn use-ajax btn-primary\\u0022\\u003EHacer otra consulta\\u003C\\/a\\u003E\\n\\u003C\\/p\\u003E\\n\\u003C\\/div\\u003E"""
print(html.replace("\\/", "/").encode().decode('unicode_escape'))

Reset Windows Activation/Remove license key

  1. Open a command prompt as an Administrator.

  2. Enter slmgr /upk and wait for this to complete. This will uninstall the current product key from Windows and put it into an unlicensed state.

  3. Enter slmgr /cpky and wait for this to complete. This will remove the product key from the registry if it's still there.

  4. Enter slmgr /rearm and wait for this to complete. This is to reset the Windows activation timers so the new users will be prompted to activate Windows when they put in the key.

This should put the system back to a pre-key state.

Hope this helps you out!

How do I start a process from C#?

You can use this syntax for running any application:

System.Diagnostics.Process.Start("Example.exe");

And the same one for a URL. Just write your URL between this ().

Example:

System.Diagnostics.Process.Start("http://www.google.com");

What are examples of TCP and UDP in real life?

Real life examples of both TCP and UDP tcp -> a phone call, sms or anything specific to destination UDP -> a FM radio channel (AM), Wi-Fi.

C++ printing spaces or tabs given a user input integer

Just use std::string:

std::cout << std::string( n, ' ' );

In many cases, however, depending on what comes next, is may be simpler to just add n to the parameter to an std::setw.

C++ undefined reference to defined function

As Paul said, this can be a linker complaint, rather than a compiler error. If you read your build output/logs carefully (may need to look in a separate IDE window to see the full details) you can dell if the problem is from the compiler (needs to be fixed in code) or from the linker (and need to be fixed in the make/cmake/project level to include a missing lib).

What is the difference between range and xrange functions in Python 2.X?

xrange returns an iterator and only keeps one number in memory at a time. range keeps the entire list of numbers in memory.

T-sql - determine if value is integer

Why not just do something like:

CASE
WHEN ROUND(MY_FIELD,0)=MY_FIELD THEN CAST(MY_FIELD AS INT)
ELSE MY_FIELD
END
as MY_FIELD2

Split a string into array in Perl

Having $line as it is now, you can simply split the string based on at least one whitespace separator

my @answer = split(' ', $line); # creates an @answer array

then

print("@answer\n");               # print array on one line

or

print("$_\n") for (@answer);      # print each element on one line

I prefer using () for split, print and for.

Shell script to capture Process ID and kill it if exist

This should kill all processes matching the grep that you are permitted to kill.

-9 means "Kill all processes you can kill".

kill -9 $(ps -ef | grep [s]yncapp | awk '{print $2}')

Is arr.__len__() the preferred way to get the length of an array in Python?

Python suggests users use len() instead of __len__() for consistency, just like other guys said. However, There're some other benefits:

For some built-in types like list, str, bytearray and so on, the Cython implementation of len() takes a shortcut. It directly returns the ob_size in a C structure, which is faster than calling __len__().

If you are interested in such details, you could read the book called "Fluent Python" by Luciano Ramalho. There're many interesting details in it, and may help you understand Python more deeply.

Lock down Microsoft Excel macro

you can set a password to your vba code but this can be quite easily broken up.

you can also create an addin and compile it into a DLL. See here for more information. That's at least the most secure way to protect your code.

Regards,

How can I save multiple documents concurrently in Mongoose/Node.js?

Here is another way without using additional libraries (no error checking included)

function saveAll( callback ){
  var count = 0;
  docs.forEach(function(doc){
      doc.save(function(err){
          count++;
          if( count == docs.length ){
             callback();
          }
      });
  });
}

How do I close a tkinter window?

import Tkinter as tk

def quit(root):
    root.destroy()

root = tk.Tk()
tk.Button(root, text="Quit", command=lambda root=root:quit(root)).pack()
root.mainloop()

Remove '\' char from string c#

Trim only removes characters at the beginning and the end of the string, that's why your code doesn't quite work. You should use Replace instead:

line.Replace(@"\", string.Empty);

How to parse a string into a nullable int

I suggest code bellow. You may work with exception, when convert error occured.

public static class Utils {      
public static bool TryParse<Tin, Tout>(this Tin obj, Func<Tin, Tout> onConvert, Action<Tout> onFill, Action<Exception> onError) {
  Tout value = default(Tout);
  bool ret = true;
  try {
    value = onConvert(obj);
  }
  catch (Exception exc) {
    onError(exc);
    ret = false;
  }
  if (ret)
    onFill(value);
  return ret;
}

public static bool TryParse(this string str, Action<int?> onFill, Action<Exception> onError) {
  return Utils.TryParse(str
    , s => string.IsNullOrEmpty(s) ? null : (int?)int.Parse(s)
    , onFill
    , onError);
}
public static bool TryParse(this string str, Action<int> onFill, Action<Exception> onError) {
  return Utils.TryParse(str
    , s => int.Parse(s)
    , onFill
    , onError);
}
}

Use this extension method in code (fill int? Age property of a person class):

string ageStr = AgeTextBox.Text;
Utils.TryParse(ageStr, i => person.Age = i, exc => { MessageBox.Show(exc.Message); });

OR

AgeTextBox.Text.TryParse(i => person.Age = i, exc => { MessageBox.Show(exc.Message); });

How to get the first word in the string

Don't need a regex. string[: string.find(' ')]

Convert String to double in Java

This is what I would do

    public static double convertToDouble(String temp){
       String a = temp;
       //replace all commas if present with no comma
       String s = a.replaceAll(",","").trim(); 
      // if there are any empty spaces also take it out.          
      String f = s.replaceAll(" ", ""); 
      //now convert the string to double
      double result = Double.parseDouble(f); 
    return result; // return the result
}

For example you input the String "4 55,63. 0 " the output will the double number 45563.0

Checking something isEmpty in Javascript?

Empty check on a JSON's key depends on use-case. For a common use-case, we can test for following:

  1. Not null
  2. Not undefined
  3. Not an empty String ''
  4. Not an empty Object {} [] (Array is an Object)

Function:

function isEmpty(arg){
  return (
    arg == null || // Check for null or undefined
    arg.length === 0 || // Check for empty String (Bonus check for empty Array)
    (typeof arg === 'object' && Object.keys(arg).length === 0) // Check for empty Object or Array
  );
}

Return true for:

isEmpty(''); // Empty String
isEmpty(null); // null
isEmpty(); // undefined
isEmpty({}); // Empty Object
isEmpty([]); // Empty Array

How to access array elements in a Django template?

when you render a request tou coctext some information: for exampel:

return render(request, 'path to template',{'username' :username , 'email'.email})

you can acces to it on template like this : for variabels :

{% if username %}{{ username }}{% endif %}

for array :

{% if username %}{{ username.1 }}{% endif %}
{% if username %}{{ username.2 }}{% endif %}

you can also name array objects in views.py and ten use it like:

{% if username %}{{ username.first }}{% endif %}

if there is other problem i wish to help you

SELECT INTO USING UNION QUERY

You have to define a table alias for a derived table in SQL Server:

SELECT x.* 
  INTO [NEW_TABLE]
  FROM (SELECT * FROM TABLE1
        UNION
        SELECT * FROM TABLE2) x

"x" is the table alias in this example.

no pg_hba.conf entry for host

To resolve this problem, you can try this.

first, you have found out your pg_hba.conf by:

cd /etc/postgresql/9.5/main from your root directory

and open file using

sudo nano pg_hba.conf

then add this line:

local   all         all                               md5

to your pg_hba.conf and then restart by using the command:

sudo service postgresql restart

How to find controls in a repeater header or footer

The best and clean way to do this is within the Item_Created Event :

 protected void rptSummary_ItemCreated(Object sender, RepeaterItemEventArgs e)
        {
            switch (e.Item.ItemType)
            {
                case ListItemType.AlternatingItem:
                    break;
                case ListItemType.EditItem:
                    break;
                case ListItemType.Footer:
                    e.Item.FindControl(ctrl);
                    break;
                case ListItemType.Header:
                    break;
                case ListItemType.Item:
                    break;
                case ListItemType.Pager:
                    break;
                case ListItemType.SelectedItem:
                    break;
                case ListItemType.Separator:
                    break;
                default:
                    break;
            }
    }

How do you change text to bold in Android?

It's very easy

setTypeface(Typeface.DEFAULT_BOLD);

python, sort descending dataframe with pandas

from pandas import DataFrame
import pandas as pd

d = {'one':[2,3,1,4,5],
 'two':[5,4,3,2,1],
 'letter':['a','a','b','b','c']}

df = DataFrame(d)

test = df.sort_values(['one'], ascending=False)
test

How to Retrieve value from JTextField in Java Swing?

How do we retrieve a value from a text field?

mytestField.getText();

ActionListner example:

mytextField.addActionListener(this);

public void actionPerformed(ActionEvent evt) {
    String text = textField.getText();
    textArea.append(text + newline);
    textField.selectAll();
}

How to crop an image in OpenCV using Python

Robust crop with opencv copy border function:

def imcrop(img, bbox):
   x1, y1, x2, y2 = bbox
   if x1 < 0 or y1 < 0 or x2 > img.shape[1] or y2 > img.shape[0]:
        img, x1, x2, y1, y2 = pad_img_to_fit_bbox(img, x1, x2, y1, y2)
   return img[y1:y2, x1:x2, :]

def pad_img_to_fit_bbox(img, x1, x2, y1, y2):
    img = cv2.copyMakeBorder(img, - min(0, y1), max(y2 - img.shape[0], 0),
                            -min(0, x1), max(x2 - img.shape[1], 0),cv2.BORDER_REPLICATE)
   y2 += -min(0, y1)
   y1 += -min(0, y1)
   x2 += -min(0, x1)
   x1 += -min(0, x1)
   return img, x1, x2, y1, y2

Oracle SQL - select within a select (on the same table!)

I'm a bit confused by the quotes, however, below should work for you:

SELECT "Gc_Staff_Number",
       "Start_Date", x.end_date
FROM   "Employment_History" eh,
(SELECT "End_Date"
        FROM   "Employment_History"
        WHERE  "Current_Flag" != 'Y'
               AND ROWNUM = 1
               AND "Employee_Number" = eh.Employee_Number
        ORDER  BY "End_Date" ASC) x
WHERE  "Current_Flag" = 'Y'

What is the equivalent of Java static methods in Kotlin?

You can achieve the static functionality in Kotlin by Companion Objects

  • Adding companion to the object declaration allows for adding the static functionality to an object even though the actual static concept does not exist in Kotlin.
  • A companion object can access all members of the class too, including the private constructors.
  • A companion object is initialized when the class is instantiated.
  • A companion object cannot be declared outside the class.

    class MyClass{
    
        companion object {
    
            val staticField = "This is an example of static field Object Decleration"
    
            fun getStaticFunction(): String {
                return "This is example of static function for Object Decleration"
            }
    
        }
    }
    

Members of the companion object can be called by using simply the class name as the qualifier:

Output:

MyClass.staticField // This is an example of static field Object Decleration

MyClass.getStaticFunction() : // This is an example of static function for Object Decleration

How to connect mySQL database using C++

Yes, you will need the mysql c++ connector library. Read on below, where I explain how to get the example given by mysql developers to work.

Note(and solution): IDE: I tried using Visual Studio 2010, but just a few sconds ago got this all to work, it seems like I missed it in the manual, but it suggests to use Visual Studio 2008. I downloaded and installed VS2008 Express for c++, followed the steps in chapter 5 of manual and errors are gone! It works. I'm happy, problem solved. Except for the one on how to get it to work on newer versions of visual studio. You should try the mysql for visual studio addon which maybe will get vs2010 or higher to connect successfully. It can be downloaded from mysql website

Whilst trying to get the example mentioned above to work, I find myself here from difficulties due to changes to the mysql dev website. I apologise for writing this as an answer, since I can't comment yet, and will edit this as I discover what to do and find the solution, so that future developers can be helped.(Since this has gotten so big it wouldn't have fitted as a comment anyways, haha)

@hd1 link to "an example" no longer works. Following the link, one will end up at the page which gives you link to the main manual. The main manual is a good reference, but seems to be quite old and outdated, and difficult for new developers, since we have no experience especially if we missing a certain file, and then what to add.

@hd1's link has moved, and can be found with a quick search by removing the url components, keeping just the article name, here it is anyways: http://dev.mysql.com/doc/connector-cpp/en/connector-cpp-examples-complete-example-1.html

Getting 7.5 MySQL Connector/C++ Complete Example 1 to work

Downloads:

-Get the mysql c++ connector, even though it is bigger choose the installer package, not the zip.

-Get the boost libraries from boost.org, since boost is used in connection.h and mysql_connection.h from the mysql c++ connector

Now proceed:

-Install the connector to your c drive, then go to your mysql server install folder/lib and copy all libmysql files, and paste in your connector install folder/lib/opt

-Extract the boost library to your c drive

Next:

It is alright to copy the code as it is from the example(linked above, and ofcourse into a new c++ project). You will notice errors:

-First: change

cout << "(" << __FUNCTION__ << ") on line " »
 << __LINE__ << endl;

to

cout << "(" << __FUNCTION__ << ") on line " << __LINE__ << endl;

Not sure what that tiny double arrow is for, but I don't think it is part of c++

-Second: Fix other errors of them by reading Chapter 5 of the sql manual, note my paragraph regarding chapter 5 below

[Note 1]: Chapter 5 Building MySQL Connector/C++ Windows Applications with Microsoft Visual Studio If you follow this chapter, using latest c++ connecter, you will likely see that what is in your connector folder and what is shown in the images are quite different. Whether you look in the mysql server installation include and lib folders or in the mysql c++ connector folders' include and lib folders, it will not match perfectly unless they update the manual, or you had a magic download, but for me they don't match with a connector download initiated March 2014.

Just follow that chapter 5,

-But for c/c++, General, Additional Include Directories include the "include" folder from the connector you installed, not server install folder

-While doing the above, also include your boost folder see note 2 below

-And for the Linker, General.. etc use the opt folder from connector/lib/opt

*[Note 2]*A second include needs to happen, you need to include from the boost library variant.hpp, this is done the same as above, add the main folder you extracted from the boost zip download, not boost or lib or the subfolder "variant" found in boostmainfolder/boost.. Just the main folder as the second include

Next:

What is next I think is the Static Build, well it is what I did anyways. Follow it.

Then build/compile. LNK errors show up(Edit: Gone after changing ide to visual studio 2008). I think it is because I should build connector myself(if you do this in visual studio 2010 then link errors should disappear), but been working on trying to get this to work since Thursday, will see if I have the motivation to see this through after a good night sleep(and did and now finished :) ).

Renaming part of a filename

I like to do this with sed. In you case:

for x in DET01-*.dat; do
    echo $x | sed -r 's/DET01-ABC-(.+)\.dat/mv -v "\0" "DET01-XYZ-\1.dat"/'
done | sh -e

It is best to omit the "sh -e" part first to see what will be executed.

How can I get the last 7 characters of a PHP string?

umh.. like that?

$newstring = substr($dynamicstring, -7);

Fatal error: Class 'SoapClient' not found

Diagnose

Look up the following inside your script file

phpinfo();

If you can't find Soap Client set to enabled like so: the way soap should appear in phpinfo()

Fix

Do the following:

  1. Locate php.ini in your apache bin folder, I.e Apache/bin/php.ini
  2. Remove the ; from the beginning of extension=php_soap.dll
  3. Restart your Apache server
  4. Look up your phpinfo(); again and check if you see a similar picture to the one above
  5. If you do, problem solved!

On the other hand if this doesn't solve your issue, you may want to check the requirements for SOAP here. Also in the comment section you can find good advice on connecting to https.

How to programmatically open the Permission Screen for a specific app on Android Marshmallow?

If we are talking about FLYME OS (Meizu) ONLY there are it's own Security app with permissions.

To open it use following intent:

public static void openFlymeSecurityApp(Activity context) {
    Intent intent = new Intent("com.meizu.safe.security.SHOW_APPSEC");
    intent.addCategory(Intent.CATEGORY_DEFAULT);
    intent.putExtra("packageName", BuildConfig.APPLICATION_ID);
    try {
        context.startActivity(intent);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

Of-cause BuildConfig is your app's BuildConfig.

Input jQuery get old value before onchange and get value after on change

My business aim was removing classes form previous input and add it to a new one.
In this case there was simple solution: remove classes from all inputs before add

<div>
   <input type="radio" checked><b class="darkred">Value1</b>
   <input type="radio"><b>Value2</b>
   <input type="radio"><b>Value3</b>
</div>

and

$('input[type="radio"]').on('change', function () {
   var current = $(this);
   current.closest('div').find('input').each(function () {
       (this).next().removeClass('darkred')
   });
   current.next().addClass('darkred');
});

JsFiddle: http://jsfiddle.net/gkislin13/tybp8skL

How to re-sync the Mysql DB if Master and slave have different database incase of Mysql replication?

Here is a complete answer that will hopefully help others...


I want to setup mysql replication using master and slave, and since the only thing I knew was that it uses log file(s) to synchronize, if the slave goes offline and gets out of sync, in theory it should only need to connect back to its master and keep reading the log file from where it left off, as user malonso mentioned.

So here are the test result after configuring the master and slave as mentioned by: http://dev.mysql.com/doc/refman/5.0/en/replication-howto.html ...

Provided you use the recommended master/slave configuration and don't write to the slave, he and I where right (as far as mysql-server 5.x is concerned). I didn't even need to use "START SLAVE;", it just caught up to its master. But there is a default 88000 something retries every 60 second so I guess if you exhaust that you might have to start or restart the slave. Anyways, for those like me who wanted to know if having a slave going offline and back up again requires manual intervention.. no, it doesn't.

Maybe the original poster had corruption in the log-file(s)? But most probably not just a server going off-line for a day.


pulled from /usr/share/doc/mysql-server-5.1/README.Debian.gz which probably makes sense to non debian servers as well:

* FURTHER NOTES ON REPLICATION
===============================
If the MySQL server is acting as a replication slave, you should not
set --tmpdir to point to a directory on a memory-based filesystem or to
a directory that is cleared when the server host restarts. A replication
slave needs some of its temporary files to survive a machine restart so
that it can replicate temporary tables or LOAD DATA INFILE operations. If
files in the temporary file directory are lost when the server restarts,
replication fails.

you can use something sql like: show variables like 'tmpdir'; to find out.

How to bring a window to the front?

Windows has the facility to prevent windows from stealing focus; instead it flashes the taskbar icon. In XP it's on by default (the only place I've seen to change it is using TweakUI, but there is a registry setting somewhere). In Vista they may have changed the default and/or exposed it as a user accessible setting with the out-of-the-box UI.

Preventing windows from forcing themselves to the front and taking focus is a feature since Windows 2K (and I, for one, am thankful for it).

That said, I have a little Java app I use to remind me to record my activities while working, and it makes itself the active window every 30 minutes (configurable, of course). It always works consistently under Windows XP and never flashes the title bar window. It uses the following code, called in the UI thread as a result of a timer event firing:

if(getState()!=Frame.NORMAL) { setState(Frame.NORMAL); }
toFront();
repaint();

(the first line restores if minimized... actually it would restore it if maximized too, but I never have it so).

While I usually have this app minimized, quite often it's simply behind my text editor. And, like I said, it always works.

I do have an idea on what your problem could be - perhaps you have a race condition with the setVisible() call. toFront() may not be valid unless the window is actually displayed when it is called; I have had this problem with requestFocus() before. You may need to put the toFront() call in a UI listener on a window activated event.

2014-09-07: At some point in time the above code stopped working, perhaps at Java 6 or 7. After some investigation and experimentation I had to update the code to override the window's toFront method do this (in conjunction with modified code from what is above):

setVisible(true);
toFront();
requestFocus();
repaint();

...

public @Override void toFront() {
    int sta = super.getExtendedState() & ~JFrame.ICONIFIED & JFrame.NORMAL;

    super.setExtendedState(sta);
    super.setAlwaysOnTop(true);
    super.toFront();
    super.requestFocus();
    super.setAlwaysOnTop(false);
}

As of Java 8_20, this code seems to be working fine.

How to make a radio button unchecked by clicking it?

If you are looking for solution in jQuery here it is. It is similar to this

_x000D_
_x000D_
    $('input:radio').click(function() { 
      let name = $(this).attr('name');
      let self = $(this);
      [].filter.call($(`input[name=${name}]`), function(ele){
        return self[0] !== $(ele)[0];
      }).forEach(function(otherEle){
        $(otherEle).removeAttr('data-check');
      });

      if($(this).attr('data-check')){
        $(this).prop("checked", false);
        $(this).removeAttr('data-check');
      }else{
        $(this).attr("data-check", "1");
      }
    });
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<form>
  <input class="radio" name="A" type="radio">A
  <input class="radio" name="A" type="radio">B
  <input class="radio" name="A" type="radio">C
</form>

<form>
  <input class="radio" name="B" type="radio">D
  <input class="radio" name="B" type="radio">E
  <input class="radio" name="B" type="radio">F
</form>

<form>
  <input class="radio" name="C" type="radio">G
  <input class="radio" name="C" type="radio">H
  <input class="radio" name="C" type="radio">I
</form>
_x000D_
_x000D_
_x000D_

select count(*) from table of mysql in php

You can as well use this and upgrade to mysqli_ (stop using mysql_* extension...)

$result = mysqli_query($conn, "SELECT COUNT(*) AS `count` FROM `Students`");
$row = mysqli_fetch_array($result);
$count = $row['count'];
echo $count;

Get value from JToken that may not exist (best practices)

This takes care of nulls

var body = JObject.Parse("anyjsonString");

body?.SelectToken("path-string-prop")?.ToString();

body?.SelectToken("path-double-prop")?.ToObject<double>();

Insert Data Into Tables Linked by Foreign Key

Use stored procedures.

And even assuming you would want not to use stored procedures - there is at most 3 commands to be run, not 4. Second getting id is useless, as you can do "INSERT INTO ... RETURNING".

No connection could be made because the target machine actively refused it?

it might be because of authorisation issues; that was the case for me. If you have for example: [Authorize("WriteAccess")] or [Authorize("ReadAccess")] at the top of your controller functions, try to comment them out.

How to resolve "Waiting for Debugger" message?

Rebooting the PC was the only thing that worked for me. It worked when I had this problem with an Android 2.2 phone, and also an Android 3.1 tablet.

Command Prompt Error 'C:\Program' is not recognized as an internal or external command, operable program or batch file

This seems to happen from time to time with programs that are very sensitive to command lines, but one option is to just use the DOS path instead of the Windows path. This means that C:\Program Files\ would resolve to C:\PROGRA~1\ and generally avoid any issues with spacing.

To get the short path you can create a quick Batch file that echos the short path:

@ECHO OFF
echo %~s1

Which is then called as follows:

C:\>shortPath.bat "C:\Program Files"
C:\PROGRA~1

How to redirect to a different domain using NGINX?

If you would like to redirect requests for "domain1.com" to "domain2.com", you could create a server block that looks like this:

server {
    listen 80;
    server_name domain1.com;
    return 301 $scheme://domain2.com$request_uri;
}

Normal arguments vs. keyword arguments

There are two ways to assign argument values to function parameters, both are used.

  1. By Position. Positional arguments do not have keywords and are assigned first.

  2. By Keyword. Keyword arguments have keywords and are assigned second, after positional arguments.

Note that you have the option to use positional arguments.

If you don't use positional arguments, then -- yes -- everything you wrote turns out to be a keyword argument.

When you call a function you make a decision to use position or keyword or a mixture. You can choose to do all keywords if you want. Some of us do not make this choice and use positional arguments.

React Native TextInput that only accepts numeric characters

Function to validate input:

validateInputs(text, type) {
let numreg = /^[0-9]+$/;
  if (type == 'username') {
    if (numreg.test(text)) {
      //test ok
    } else {
      //test not ok
    } 
  }
}



<TextInput
   onChangeText={text => this.validateInputs(text, 'username')}
/>

I hope this is helpful.

Increase max execution time for php

Well, since your on a shared server, you can't do anything about it. They usually set the max execution time so that you can't override it. I suggest you contact them.

How to create global variables accessible in all views using Express / Node.JS?

With the differents answers, I implemented this code to use an external file JSON loaded in "app.locals"

Parameters

{
    "web": {
        "title" : "Le titre de ma Page",
        "cssFile" : "20200608_1018.css"
    }
}

Application

var express     = require('express');
var appli       = express();
var serveur     = require('http').Server(appli);

var myParams    = require('./include/my_params.json');
var myFonctions = require('./include/my_fonctions.js');

appli.locals = myParams;

EJS Page

<!DOCTYPE html>
<html lang="fr">
<head>
    <meta charset="UTF-8">
    <title><%= web.title %></title>
    <link rel="stylesheet" type="text/css" href="/css/<%= web.cssFile %>">
</head>

</body>
</html>

Hoping it will help

Node - was compiled against a different Node.js version using NODE_MODULE_VERSION 51

you need just run this below commands:

$ rm -rf node_modules
$ rm -rf yarn.lock
$ yarn install

and finally

$ ./node_modules/.bin/electron-rebuild

don't forget to yarn add electron-rebuild if it doesn't exist in your dependencies.

How to set transparent background for Image Button in code?

Do it in your xml

<ImageButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/imageButtonSettings"
        android:layout_gravity="right|bottom"
        android:src="@drawable/tabbar_settings_icon"
        android:background="@android:color/transparent"/>

powerpoint loop a series of animation

Unfortunately you're probably done with the animation and presentation already. In the hopes this answer can help future questioners, however, this blog post has a walkthrough of steps that can loop a single slide as a sort of sub-presentation.

First, click Slide Show > Set Up Show.

Put a checkmark to Loop continuously until 'Esc'.

Click Ok. Now, Click Slide Show > Custom Shows. Click New.

Select the slide you are looping, click Add. Click Ok and Close.

Click on the slide you are looping. Click Slide Show > Slide Transition. Under Advance slide, put a checkmark to Automatically After. This will allow the slide to loop automatically. Do NOT Apply to all slides.

Right click on the thumbnail of the current slide, select Hide Slide.

Now, you will need to insert a new slide just before the slide you are looping. On the new slide, insert an action button. Set the hyperlink to the custom show you have created. Put a checkmark on "Show and Return"

This has worked for me.

Iterator invalidation rules

C++11 (Source: Iterator Invalidation Rules (C++0x))


Insertion

Sequence containers

  • vector: all iterators and references before the point of insertion are unaffected, unless the new container size is greater than the previous capacity (in which case all iterators and references are invalidated) [23.3.6.5/1]
  • deque: all iterators and references are invalidated, unless the inserted member is at an end (front or back) of the deque (in which case all iterators are invalidated, but references to elements are unaffected) [23.3.3.4/1]
  • list: all iterators and references unaffected [23.3.5.4/1]
  • forward_list: all iterators and references unaffected (applies to insert_after) [23.3.4.5/1]
  • array: (n/a)

Associative containers

  • [multi]{set,map}: all iterators and references unaffected [23.2.4/9]

Unsorted associative containers

  • unordered_[multi]{set,map}: all iterators invalidated when rehashing occurs, but references unaffected [23.2.5/8]. Rehashing does not occur if the insertion does not cause the container's size to exceed z * B where z is the maximum load factor and B the current number of buckets. [23.2.5/14]

Container adaptors

  • stack: inherited from underlying container
  • queue: inherited from underlying container
  • priority_queue: inherited from underlying container

Erasure

Sequence containers

  • vector: every iterator and reference at or after the point of erase is invalidated [23.3.6.5/3]
  • deque: erasing the last element invalidates only iterators and references to the erased elements and the past-the-end iterator; erasing the first element invalidates only iterators and references to the erased elements; erasing any other elements invalidates all iterators and references (including the past-the-end iterator) [23.3.3.4/4]
  • list: only the iterators and references to the erased element is invalidated [23.3.5.4/3]
  • forward_list: only the iterators and references to the erased element is invalidated (applies to erase_after) [23.3.4.5/1]
  • array: (n/a)

Associative containers

  • [multi]{set,map}: only iterators and references to the erased elements are invalidated [23.2.4/9]

Unordered associative containers

  • unordered_[multi]{set,map}: only iterators and references to the erased elements are invalidated [23.2.5/13]

Container adaptors

  • stack: inherited from underlying container
  • queue: inherited from underlying container
  • priority_queue: inherited from underlying container

Resizing

  • vector: as per insert/erase [23.3.6.5/12]
  • deque: as per insert/erase [23.3.3.3/3]
  • list: as per insert/erase [23.3.5.3/1]
  • forward_list: as per insert/erase [23.3.4.5/25]
  • array: (n/a)

Note 1

Unless otherwise specified (either explicitly or by defining a function in terms of other functions), invoking a container member function or passing a container as an argument to a library function shall not invalidate iterators to, or change the values of, objects within that container. [23.2.1/11]

Note 2

no swap() function invalidates any references, pointers, or iterators referring to the elements of the containers being swapped. [ Note: The end() iterator does not refer to any element, so it may be invalidated. —end note ] [23.2.1/10]

Note 3

Other than the above caveat regarding swap(), it's not clear whether "end" iterators are subject to the above listed per-container rules; you should assume, anyway, that they are.

Note 4

vector and all unordered associative containers support reserve(n) which guarantees that no automatic resizing will occur at least until the size of the container grows to n. Caution should be taken with unordered associative containers because a future proposal will allow the specification of a minimum load factor, which would allow rehashing to occur on insert after enough erase operations reduce the container size below the minimum; the guarantee should be considered potentially void after an erase.

How to view table contents in Mysql Workbench GUI?

Select Database , select table and click icon as shown in picture.enter image description here

In Java, what is the best way to determine the size of an object?

I doubt you want to do it programmatically unless you just want to do it once and store it for future use. It's a costly thing to do. There's no sizeof() operator in Java, and even if there was, it would only count the cost of the references to other objects and the size of the primitives.

One way you could do it is to serialize the thing to a File and look at the size of the file, like this:

Serializable myObject;
ObjectOutputStream oos = new ObjectOutputStream (new FileOutputStream ("obj.ser"));
oos.write (myObject);
oos.close ();

Of course, this assumes that each object is distinct and doesn't contain non-transient references to anything else.

Another strategy would be to take each object and examine its members by reflection and add up the sizes (boolean & byte = 1 byte, short & char = 2 bytes, etc.), working your way down the membership hierarchy. But that's tedious and expensive and ends up doing the same thing the serialization strategy would do.

Checking if a string is empty or null in Java

import com.google.common.base

if(!Strings.isNullOrEmpty(String str)) {
   // Do your stuff here 
}

Vertical align text in block element

with thanks to Vlad's answer for inspiration; tested & working on IE11, FF49, Opera40, Chrome53

li > a {
  height: 100px;
  width: 300px;
  display: table-cell;
  text-align: center; /* H align */
  vertical-align: middle;
}

centers in all directions nicely even with text wrapping, line breaks, images, etc.

I got fancy and made a snippet

_x000D_
_x000D_
li > a {_x000D_
  height: 100px;_x000D_
  width: 300px;_x000D_
  display: table-cell;_x000D_
  /*H align*/_x000D_
  text-align: center;_x000D_
  /*V align*/_x000D_
  vertical-align: middle;_x000D_
}_x000D_
a.thin {_x000D_
  width: 40px;_x000D_
}_x000D_
a.break {_x000D_
  /*force text wrap, otherwise `width` is treated as `min-width` when encountering a long word*/_x000D_
  word-break: break-all;_x000D_
}_x000D_
/*more css so you can see this easier*/_x000D_
_x000D_
li {_x000D_
  display: inline-block;_x000D_
}_x000D_
li > a {_x000D_
  padding: 10px;_x000D_
  margin: 30px;_x000D_
  background: aliceblue;_x000D_
}_x000D_
li > a:hover {_x000D_
  padding: 10px;_x000D_
  margin: 30px;_x000D_
  background: aqua;_x000D_
}
_x000D_
<li><a href="">My menu item</a>_x000D_
</li>_x000D_
<li><a href="">My menu <br> break item</a>_x000D_
</li>_x000D_
<li><a href="">My menu item that is really long and unweildly</a>_x000D_
</li>_x000D_
<li><a href="" class="thin">Good<br>Menu<br>Item</a>_x000D_
</li>_x000D_
<li><a href="" class="thin">Fantastically Menu Item</a>_x000D_
</li>_x000D_
<li><a href="" class="thin break">Fantastically Menu Item</a>_x000D_
</li>_x000D_
<br>_x000D_
note: if using "break-all" need to also use "&lt;br>" or suffer the consequences
_x000D_
_x000D_
_x000D_

Casting an int to a string in Python

x = 1
y = "foo" + str(x)

Please see the Python documentation: https://docs.python.org/2/library/functions.html#str

Http Post With Body

You can use HttpClient and HttpPost to build and send the request.

HttpClient client= new DefaultHttpClient();
HttpPost request = new HttpPost("www.example.com");

List<NameValuePair> pairs = new ArrayList<NameValuePair>();
pairs.add(new BasicNameValuePair("paramName", "paramValue"));

request.setEntity(new UrlEncodedFormEntity(pairs ));
HttpResponse resp = client.execute(request);

How can I get the selected VALUE out of a QCombobox?

The member function QComboBox::currentData has been added since this question was asked, see this commit

AngularJS POST Fails: Response for preflight has invalid HTTP status code 404

Ok so here's how I figured this out. It all has to do with CORS policy. Before the POST request, Chrome was doing a preflight OPTIONS request, which should be handled and acknowledged by the server prior to the actual request. Now this is really not what I wanted for such a simple server. Hence, resetting the headers client side prevents the preflight:

app.config(function ($httpProvider) {
  $httpProvider.defaults.headers.common = {};
  $httpProvider.defaults.headers.post = {};
  $httpProvider.defaults.headers.put = {};
  $httpProvider.defaults.headers.patch = {};
});

The browser will now send a POST directly. Hope this helps a lot of folks out there... My real problem was not understanding CORS enough.

Link to a great explanation: http://www.html5rocks.com/en/tutorials/cors/

Kudos to this answer for showing me the way.

How can I convert a string with dot and comma into a float in Python

What about this?

 my_string = "123,456.908"
 commas_removed = my_string.replace(',', '') # remove comma separation
 my_float = float(commas_removed) # turn from string to float.

In short:

my_float = float(my_string.replace(',', ''))

matplotlib does not show my drawings although I call pyplot.show()

After running your code include:

import pylab as p
p.show()

How do I detect if I am in release or debug mode?

I am using this solution in case to find out that my app is running on debug version.

if (BuildConfig.BUILD_TYPE.equals("debug")){
   //Do something
}

How do I convert between ISO-8859-1 and UTF-8 in Java?

The easiest way to convert an ISO-8859-1 string to UTF-8 string.

private static String convertIsoToUTF8(String example) throws UnsupportedEncodingException {
    return new String(example.getBytes("ISO-8859-1"), "utf-8");
}

If we want to convert an UTF-8 string to ISO-8859-1 string.

private static String convertUTF8ToISO(String example) throws UnsupportedEncodingException {
    return new String(example.getBytes("utf-8"), "ISO-8859-1");
}

Moreover, a method that converts an ISO-8859-1 string to UTF-8 string without using the constructor of class String.

public static String convertISO_to_UTF8_personal(String strISO_8859_1) {
    String res = "";
    int i = 0;
    for (i = 0; i < strISO_8859_1.length() - 1; i++) {
        char ch = strISO_8859_1.charAt(i);
        char chNext = strISO_8859_1.charAt(i + 1);
        if (ch <= 127) {
            res += ch;
        } else if (ch == 194 && chNext >= 128 && chNext <= 191) {
            res += chNext;
        } else if(ch == 195 && chNext >= 128 && chNext <= 191){
            int resNum = chNext + 64;
            res += (char) resNum;
        } else if(ch == 194){
            res += (char) 173;
        } else if(ch == 195){
            res += (char) 224;
        }
    }
    char ch = strISO_8859_1.charAt(i);
    if (ch <= 127 ){
        res += ch;
    }
    return res;
}

}

That method is based on enconding utf-8 to iso-8859-1 of this website. Encoding utf-8 to iso-8859-1

How do I schedule a task to run at periodic intervals?

timer.scheduleAtFixedRate( new Task(), 1000,3000); 

css label width not taking effect

I believe labels are inline, and so they don't take a width. Maybe try using "display: block" and going from there.

Split a string into an array of strings based on a delimiter

You can make your own function which returns TArray of string:

function mySplit(input: string): TArray<string>;
var
  delimiterSet: array [0 .. 0] of char; 
     // split works with char array, not a single char
begin
  delimiterSet[0] := '&'; // some character
  result := input.Split(delimiterSet);
end;

How to Turn Off Showing Whitespace Characters in Visual Studio IDE

for VS code and later versions Ctrl + P to open and then writing Whitespace, you can select the View: Toggle Render Whitespace

Keeping session alive with Curl and PHP

You also need to set the option CURLOPT_COOKIEFILE.

The manual describes this as

The name of the file containing the cookie data. The cookie file can be in Netscape format, or just plain HTTP-style headers dumped into a file. If the name is an empty string, no cookies are loaded, but cookie handling is still enabled.

Since you are using the cookie jar you end up saving the cookies when the requests finish, but since the CURLOPT_COOKIEFILE is not given, cURL isn't sending any of the saved cookies on subsequent requests.