Programs & Examples On #Arraybuffer

ArrayBuffer is a Javascript data type used to represent a generic, fixed-length binary data buffer.

Converting between strings and ArrayBuffers

Yes:

const encstr = (`TextEncoder` in window) ? new TextEncoder().encode(str) : Uint8Array.from(str, c => c.codePointAt(0));

How to go from Blob to ArrayBuffer

This is an async method which first checks for the availability of arrayBuffer method. This function is backward compatible and future proof.

async function blobToArrayBuffer(blob) {
    if ('arrayBuffer' in blob) return await blob.arrayBuffer();
    
    return new Promise((resolve, reject) => {
        const reader = new FileReader();
        reader.onload = () => resolve(reader.result);
        reader.onerror = () => reject;
        reader.readAsArrayBuffer(blob);
    });
}

Conversion between UTF-8 ArrayBuffer and String

The methods readAsArrayBuffer and readAsText from a FileReader object converts a Blob object to an ArrayBuffer or to a DOMString asynchronous.

A Blob object type can be created from a raw text or byte array, for example.

let blob = new Blob([text], { type: "text/plain" });

let reader = new FileReader();
reader.onload = event =>
{
    let buffer = event.target.result;
};
reader.readAsArrayBuffer(blob);

I think it's better to pack up this in a promise:

function textToByteArray(text)
{
    let blob = new Blob([text], { type: "text/plain" });
    let reader = new FileReader();
    let done = function() { };

    reader.onload = event =>
    {
        done(new Uint8Array(event.target.result));
    };
    reader.readAsArrayBuffer(blob);

    return { done: function(callback) { done = callback; } }
}

function byteArrayToText(bytes, encoding)
{
    let blob = new Blob([bytes], { type: "application/octet-stream" });
    let reader = new FileReader();
    let done = function() { };

    reader.onload = event =>
    {
        done(event.target.result);
    };

    if(encoding) { reader.readAsText(blob, encoding); } else { reader.readAsText(blob); }

    return { done: function(callback) { done = callback; } }
}

let text = "\uD83D\uDCA9 = \u2661";
textToByteArray(text).done(bytes =>
{
    console.log(bytes);
    byteArrayToText(bytes, 'UTF-8').done(text => 
    {
        console.log(text); //  = ?
    });
});

Convert a binary NodeJS Buffer to JavaScript ArrayBuffer

Use the following excellent npm package: to-arraybuffer.

Or, you can implement it yourself. If your buffer is called buf, do this:

buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength)

ArrayBuffer to base64 encoded string

The OP did not specify the Running Enviroment but if you are using Node.JS there is a very simple way to do such thing.

Accordig with the official Node.JS docs https://nodejs.org/api/buffer.html#buffer_buffers_and_character_encodings

// This step is only necessary if you don't already have a Buffer Object
const buffer = Buffer.from(yourArrayBuffer);

const base64String = buffer.toString('base64');

Also, If you are running under Angular for example, the Buffer Class will also be made available in a Browser Environment.

Convert base64 string to ArrayBuffer

I would strongly suggest using an npm package implementing correctly the base64 specification.

The best one I know is rfc4648

The problem is that btoa and atob use binary strings instead of Uint8Array and trying to convert to and from it is cumbersome. Also there is a lot of bad packages in npm for that. I lose a lot of time before finding that one.

The creators of that specific package did a simple thing: they took the specification of Base64 (which is here by the way) and implemented it correctly from the beginning to the end. (Including other formats in the specification that are also useful like Base64-url, Base32, etc ...) That doesn't seem a lot but apparently that was too much to ask to the bunch of other libraries.

So yeah, I know I'm doing a bit of proselytism but if you want to avoid losing your time too just use rfc4648.

Float right and position absolute doesn't work together

Use

position:absolute; right: 0;

No need for float:right with absolute positioning

Also, make sure the parent element is set to position:relative;

ORDER BY using Criteria API

You can add join type as well:

Criteria c2 = c.createCriteria("mother", "mother", CriteriaSpecification.LEFT_JOIN);
Criteria c3 = c2.createCriteria("kind", "kind", CriteriaSpecification.LEFT_JOIN);

Sorting objects by property values

With ES6 arrow functions it will be like this:

//Let's say we have these cars
let cars = [ { brand: 'Porsche', top_speed: 260 },
  { brand: 'Benz', top_speed: 110 },
  { brand: 'Fiat', top_speed: 90 },
  { brand: 'Aston Martin', top_speed: 70 } ]

Array.prototype.sort() can accept a comparator function (here I used arrow notation, but ordinary functions work the same):

let sortedByBrand = [...cars].sort((first, second) => first.brand > second.brand)

// [ { brand: 'Aston Martin', top_speed: 70 },
//   { brand: 'Benz', top_speed: 110 },
//   { brand: 'Fiat', top_speed: 90 },
//   { brand: 'Porsche', top_speed: 260 } ]

The above approach copies the contents of cars array into a new one and sorts it alphabetically based on brand names. Similarly, you can pass a different function:

let sortedBySpeed =[...cars].sort((first, second) => first.top_speed > second.top_speed)

//[ { brand: 'Aston Martin', top_speed: 70 },
//  { brand: 'Fiat', top_speed: 90 },
//  { brand: 'Benz', top_speed: 110 },
//  { brand: 'Porsche', top_speed: 260 } ]

If you don't mind mutating the orginal array cars.sort(comparatorFunction) will do the trick.

Convert UTF-8 to base64 string

It's a little difficult to tell what you're trying to achieve, but assuming you're trying to get a Base64 string that when decoded is abcdef==, the following should work:

byte[] bytes = Encoding.UTF8.GetBytes("abcdef==");
string base64 = Convert.ToBase64String(bytes);
Console.WriteLine(base64);

This will output: YWJjZGVmPT0= which is abcdef== encoded in Base64.

Edit:

To decode a Base64 string, simply use Convert.FromBase64String(). E.g.

string base64 = "YWJjZGVmPT0=";
byte[] bytes = Convert.FromBase64String(base64);

At this point, bytes will be a byte[] (not a string). If we know that the byte array represents a string in UTF8, then it can be converted back to the string form using:

string str = Encoding.UTF8.GetString(bytes);
Console.WriteLine(str);

This will output the original input string, abcdef== in this case.

How to use string.substr() function?

You can get the above output using following code in c

#include<stdio.h>
#include<conio.h>
#include<string.h>
int main()
{
  char *str;
  clrscr();
  printf("\n Enter the string");
  gets(str);
  for(int i=0;i<strlen(str)-1;i++)
  {
    for(int j=i;j<=i+1;j++)
      printf("%c",str[j]);
    printf("\t");
  }
  getch();
  return 0;
}

1064 error in CREATE TABLE ... TYPE=MYISAM

A complementary note about CREATE TABLE .. TYPE="" syntax in SQL dump files

TLDR: If you still get CREATE TABLE ... TYPE="..." statements in SQL dump files generated by third party tools, it most certainly indicates that your server is configured to use a default sqlmode of MYSQL40 or MYSQL323.

Long story

As it was said by others, the TYPE argument to CREATE TABLE has been deprecated for a long time in MySQL. mysqldump correctly uses the ENGINE argument, unless you specifically ask it to generate a backward compatible dump (for example using --compatible=mysql40 in versions of mysqldump up to 5.7).

However, many external SQL dump tools (for example, those integrated in MySQL clients such as phpmyadmin, Navicat and DBVisualizer, as well as those used by external automated backup services such as iControlWP) are not specifically aware of this change, and instead rely on the SHOW CREATE TABLE ... command to provide table creation statements for each tables (and just to it make it clear: this is actually a good thing). However, the SHOW CREATE TABLE will actually produce outdated syntax, including the TYPE argument, if the sqlmode variable is set to MYSQL40 or MYSQL323.

Therefore, if you still get CREATE TABLE ... TYPE="..." statements in SQL dump files generated by third party tools, it most certainly indicates that your server is configured to use a default sqlmode of MYSQL40 or MYSQL323.

These sqlmodes basically configure MySQL to retain some backward compatible behaviours, and using them by default was largely recommended a few years ago. It is however highly improbable that you still have any code that wouldn't work correctly without these modes. Anyway, MYSQL40, MYSQL323 and several other similar sqlmodes have themselves been deprecated and are not supported in MySQL 8.0 and higher.

If your server is still configured with these sqlmodes and you are worried that some legacy program might fail if you change these, then one possibility is to set the sqlmode locally for that program, by executing SET SESSION sql_mode = 'MYSQL40'; immediately after connection. Note that this should only be considered as a temporary patch, and will not work in MySQL 8.0 and higher.

A more future-proof solution that do not involve rewriting your SQL queries would be to determine exactly which compatibility features need to be enable, and to enable only those, on a per-program basis (as described previously). The default sqlmode (that is, in server's configuration) should ideally be left unset (which will use official MySQL defaults for your current version). The full list of sqlmode (as of MySQL 5.7) is described here: https://dev.mysql.com/doc/refman/5.7/en/sql-mode.html.

How can I list all the deleted files in a Git repository?

This does what you want, I think:

git log --all --pretty=format: --name-only --diff-filter=D | sort -u

... which I've just taken more-or-less directly from this other answer.

Position absolute but relative to parent

#father {
   position: relative;
}

#son1 {
   position: absolute;
   top: 0;
}

#son2 {
   position: absolute;
   bottom: 0;
}

This works because position: absolute means something like "use top, right, bottom, left to position yourself in relation to the nearest ancestor who has position: absolute or position: relative."

So we make #father have position: relative, and the children have position: absolute, then use top and bottom to position the children.

How to send a header using a HTTP request through a curl call?

I use Postman.

Execute whatever call you want to do. Then, postman provides a handy tool to show the curl code .

Run it in the terminal. enter image description here

enter image description here

jQuery send HTML data through POST

As far as you're concerned once you've "pulled out" the contents with something like .html() it's just a string. You can test that with

<html> 
  <head>
    <title>runthis</title>
    <script type="text/javascript" language="javascript" src="jquery-1.3.2.js"></script>
    <script type="text/javascript">
        $(document).ready( function() {
            var x = $("#foo").html();
            alert( typeof(x) );
        });
    </script>
    </head>
    <body>
        <div id="foo"><table><tr><td>x</td></tr></table><span>xyz</span></div>
    </body>
</html>

The alert text is string. As long as you don't pass it to a parser there's no magic about it, it's a string like any other string.
There's nothing that hinders you from using .post() to send this string back to the server.

edit: Don't pass a string as the parameter data to .post() but an object, like

var data = {
  id: currid,
  html: div_html
};
$.post("http://...", data, ...);

jquery will handle the encoding of the parameters.
If you (for whatever reason) want to keep your string you have to encode the values with something like escape().

var data = 'id='+ escape(currid) +'&html='+ escape(div_html);

Errors in SQL Server while importing CSV file despite varchar(MAX) being used for each column

Goto Advanced tab----> data type of column---> Here change data type from DT_STR to DT_TEXT and column width 255. Now you can check it will work perfectly.

XCOPY switch to create specified directory if it doesn't exist?

Simple short answer is this:

xcopy /Y /I "$(SolutionDir)<my-src-path>" "$(SolutionDir)<my-dst-path>\"

Creating multiple log files of different content with log4j

Demo link: https://github.com/RazvanSebastian/spring_multiple_log_files_demo.git

My solution is based on XML configuration using spring-boot-starter-log4j. The example is a basic example using spring-boot-starter and the two Loggers writes into different log files.

Mutex example / tutorial?

Here goes my humble attempt to explain the concept to newbies around the world: (a color coded version on my blog too)

A lot of people run to a lone phone booth (they don't have mobile phones) to talk to their loved ones. The first person to catch the door-handle of the booth, is the one who is allowed to use the phone. He has to keep holding on to the handle of the door as long as he uses the phone, otherwise someone else will catch hold of the handle, throw him out and talk to his wife :) There's no queue system as such. When the person finishes his call, comes out of the booth and leaves the door handle, the next person to get hold of the door handle will be allowed to use the phone.

A thread is : Each person
The mutex is : The door handle
The lock is : The person's hand
The resource is : The phone

Any thread which has to execute some lines of code which should not be modified by other threads at the same time (using the phone to talk to his wife), has to first acquire a lock on a mutex (clutching the door handle of the booth). Only then will a thread be able to run those lines of code (making the phone call).

Once the thread has executed that code, it should release the lock on the mutex so that another thread can acquire a lock on the mutex (other people being able to access the phone booth).

[The concept of having a mutex is a bit absurd when considering real-world exclusive access, but in the programming world I guess there was no other way to let the other threads 'see' that a thread was already executing some lines of code. There are concepts of recursive mutexes etc, but this example was only meant to show you the basic concept. Hope the example gives you a clear picture of the concept.]

With C++11 threading:

#include <iostream>
#include <thread>
#include <mutex>

std::mutex m;//you can use std::lock_guard if you want to be exception safe
int i = 0;

void makeACallFromPhoneBooth() 
{
    m.lock();//man gets a hold of the phone booth door and locks it. The other men wait outside
      //man happily talks to his wife from now....
      std::cout << i << " Hello Wife" << std::endl;
      i++;//no other thread can access variable i until m.unlock() is called
      //...until now, with no interruption from other men
    m.unlock();//man lets go of the door handle and unlocks the door
}

int main() 
{
    //This is the main crowd of people uninterested in making a phone call

    //man1 leaves the crowd to go to the phone booth
    std::thread man1(makeACallFromPhoneBooth);
    //Although man2 appears to start second, there's a good chance he might
    //reach the phone booth before man1
    std::thread man2(makeACallFromPhoneBooth);
    //And hey, man3 also joined the race to the booth
    std::thread man3(makeACallFromPhoneBooth);

    man1.join();//man1 finished his phone call and joins the crowd
    man2.join();//man2 finished his phone call and joins the crowd
    man3.join();//man3 finished his phone call and joins the crowd
    return 0;
}

Compile and run using g++ -std=c++0x -pthread -o thread thread.cpp;./thread

Instead of explicitly using lock and unlock, you can use brackets as shown here, if you are using a scoped lock for the advantage it provides. Scoped locks have a slight performance overhead though.

How to transfer paid android apps from one google account to another google account

You will not be able to do that. You can download apps again to the same userid account on different devices, but you cannot transfer those licenses to other userids.

There is no way to do this programatically - I don't think you can do that practically (except for trying to call customer support at the Play Store).

Converting list to *args when calling function

*args just means that the function takes a number of arguments, generally of the same type.

Check out this section in the Python tutorial for more info.

How to kill all active and inactive oracle sessions for user

BEGIN
  FOR r IN (select sid,serial# from v$session where username='user')
  LOOP
      EXECUTE IMMEDIATE 'alter system kill session ''' || r.sid  || ',' || r.serial# || '''';
  END LOOP;
END;
/

It works for me.

How to get access token from FB.login method in javascript SDK

_x000D_
_x000D_
window.fbAsyncInit = function () {_x000D_
    FB.init({_x000D_
        appId: 'Your-appId',_x000D_
        cookie: false,  // enable cookies to allow the server to access _x000D_
        // the session_x000D_
        xfbml: true,  // parse social plugins on this page_x000D_
        version: 'v2.0' // use version 2.0_x000D_
    });_x000D_
};_x000D_
_x000D_
// Load the SDK asynchronously_x000D_
(function (d, s, id) {_x000D_
    var js, fjs = d.getElementsByTagName(s)[0];_x000D_
    if (d.getElementById(id)) return;_x000D_
    js = d.createElement(s); js.id = id;_x000D_
    js.src = "//connect.facebook.net/en_US/sdk.js";_x000D_
    fjs.parentNode.insertBefore(js, fjs);_x000D_
}(document, 'script', 'facebook-jssdk'));_x000D_
_x000D_
   _x000D_
function fb_login() {_x000D_
    FB.login(function (response) {_x000D_
_x000D_
        if (response.authResponse) {_x000D_
            console.log('Welcome!  Fetching your information.... ');_x000D_
            //console.log(response); // dump complete info_x000D_
            access_token = response.authResponse.accessToken; //get access token_x000D_
            user_id = response.authResponse.userID; //get FB UID_x000D_
_x000D_
            FB.api('/me', function (response) {_x000D_
                var email = response.email;_x000D_
                var name = response.name;_x000D_
                window.location = 'http://localhost:12962/Account/FacebookLogin/' + email + '/' + name;_x000D_
                // used in my mvc3 controller for //AuthenticationFormsAuthentication.SetAuthCookie(email, true);          _x000D_
            });_x000D_
_x000D_
        } else {_x000D_
            //user hit cancel button_x000D_
            console.log('User cancelled login or did not fully authorize.');_x000D_
_x000D_
        }_x000D_
    }, {_x000D_
        scope: 'email'_x000D_
    });_x000D_
}
_x000D_
<!-- custom image -->_x000D_
<a href="#" onclick="fb_login();"><img src="/Public/assets/images/facebook/facebook_connect_button.png" /></a>_x000D_
_x000D_
<!-- Facebook button -->_x000D_
<fb:login-button scope="public_profile,email" onlogin="fb_login();">_x000D_
                </fb:login-button>
_x000D_
_x000D_
_x000D_

IndentationError: unindent does not match any outer indentation level

in my case, the problem was the configuration of pydev on Eclipse

pydev @ Eclipse

Permission denied: /var/www/abc/.htaccess pcfg_openfile: unable to check htaccess file, ensure it is readable?

If it gets into the selinux arena you've got a much more complicated issue. It's not a good idea to remove the selinux protection but to embrace it and use the tools that were designed to manage it.

If you are serving content out of /var/www/abc, you can verify the selinux permissions with a Z appended to the normal ls -l command. i.e. ls -laZ will give the selinux context.

To add a directory to be served by selinux you can use the semanage command like this. This will change the label on /var/www/abc to httpd_sys_content_t

semanage fcontext -a -t httpd_sys_content_t /var/www/abc

this will update the label for /var/www/abc

restorecon /var/www/abc 

This answer was taken from unixmen and modified to fit this question. I had been searching for this answer for a while and finally found it so felt like I needed to share somewhere. Hope it helps someone.

Switch focus between editor and integrated terminal in Visual Studio Code

Actually, in VS Code 1.48.1, there is a toggleTerminal command; I don't know if it was available in previous versions ;) You can utilize it in the keybindings.json file.

This worked for me on Windows, and should also works on Linux.

{
    "key": "ctrl+alt+right",
    "command": "workbench.action.terminal.toggleTerminal",
    "when": "editorTextFocus || terminalFocus"
}

new DateTime() vs default(DateTime)

If you want to use default value for a DateTime parameter in a method, you can only use default(DateTime).

The following line will not compile:

    private void MyMethod(DateTime syncedTime = DateTime.MinValue)

This line will compile:

    private void MyMethod(DateTime syncedTime = default(DateTime))

Convert string date to timestamp in Python

A simple function to get UNIX Epoch time.

NOTE: This function assumes the input date time is in UTC format (Refer to comments here).

def utctimestamp(ts: str, DATETIME_FORMAT: str = "%d/%m/%Y"):
    import datetime, calendar
    ts = datetime.datetime.utcnow() if ts is None else datetime.datetime.strptime(ts, DATETIME_FORMAT)
    return calendar.timegm(ts.utctimetuple())

Usage:

>>> utctimestamp("01/12/2011")
1322697600
>>> utctimestamp("2011-12-01", "%Y-%m-%d")
1322697600

How do I redirect to the previous action in ASP.NET MVC?

try:

public ActionResult MyNextAction()
{
    return Redirect(Request.UrlReferrer.ToString());
}

alternatively, touching on what darin said, try this:

public ActionResult MyFirstAction()
{
    return RedirectToAction("MyNextAction",
        new { r = Request.Url.ToString() });
}

then:

public ActionResult MyNextAction()
{
    return Redirect(Request.QueryString["r"]);
}

How large is a DWORD with 32- and 64-bit code?

Actually, on 32-bit computers a word is 32-bit, but the DWORD type is a leftover from the good old days of 16-bit.

In order to make it easier to port programs to the newer system, Microsoft has decided all the old types will not change size.

You can find the official list here: http://msdn.microsoft.com/en-us/library/aa383751(VS.85).aspx

All the platform-dependent types that changed with the transition from 32-bit to 64-bit end with _PTR (DWORD_PTR will be 32-bit on 32-bit Windows and 64-bit on 64-bit Windows).

How to change style of a default EditText

I solved the same issue 10 minutes ago, so I will give you a short effective fix: Place this inside the application tag or your manifest:

 android:theme="@android:style/Theme.Holo"

Also set the Theme of your XML layout to Holo, in the layout's graphical view.

Libraries will be useful if you need to change more complicated theme stuff, but this little fix will work, so you can move on with your app.

How to read data of an Excel file using C#?

try
        {
            DataTable sheet1 = new DataTable("Excel Sheet");
            OleDbConnectionStringBuilder csbuilder = new OleDbConnectionStringBuilder();
            csbuilder.Provider = "Microsoft.ACE.OLEDB.12.0";
            csbuilder.DataSource = fileLocation;
            csbuilder.Add("Extended Properties", "Excel 12.0 Xml;HDR=YES");
            string selectSql = @"SELECT * FROM [Sheet1$]";
            using (OleDbConnection connection = new OleDbConnection(csbuilder.ConnectionString))
            using (OleDbDataAdapter adapter = new OleDbDataAdapter(selectSql, connection))
            {
                connection.Open();
                adapter.Fill(sheet1);
            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }

This worked for me. Please try it and let me know for queries.

Determine if running on a rooted device

I suggest using native code for root detection. Here is a full working example.

enter image description here

JAVA wrapper:

package com.kozhevin.rootchecks.util;


import android.support.annotation.NonNull;

import com.kozhevin.rootchecks.BuildConfig;

public class MeatGrinder {
    private final static String LIB_NAME = "native-lib";
    private static boolean isLoaded;
    private static boolean isUnderTest = false;

    private MeatGrinder() {

    }

    public boolean isLibraryLoaded() {
        if (isLoaded) {
            return true;
        }
        try {
            if(isUnderTest) {
                throw new UnsatisfiedLinkError("under test");
            }
            System.loadLibrary(LIB_NAME);
            isLoaded = true;
        } catch (UnsatisfiedLinkError e) {
            if (BuildConfig.DEBUG) {
                e.printStackTrace();
            }
        }
        return isLoaded;
    }

    public native boolean isDetectedDevKeys();

    public native boolean isDetectedTestKeys();

    public native boolean isNotFoundReleaseKeys();

    public native boolean isFoundDangerousProps();

    public native boolean isPermissiveSelinux();

    public native boolean isSuExists();

    public native boolean isAccessedSuperuserApk();

    public native boolean isFoundSuBinary();

    public native boolean isFoundBusyboxBinary();

    public native boolean isFoundXposed();

    public native boolean isFoundResetprop();

    public native boolean isFoundWrongPathPermission();

    public native boolean isFoundHooks();

    @NonNull
    public static MeatGrinder getInstance() {
        return InstanceHolder.INSTANCE;
    }

    private static class InstanceHolder {
        private static final MeatGrinder INSTANCE = new MeatGrinder();
    }
}

JNI wrapper(native-lib.c):

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isDetectedTestKeys(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isDetectedTestKeys();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isDetectedDevKeys(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isDetectedDevKeys();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isNotFoundReleaseKeys(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isNotFoundReleaseKeys();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundDangerousProps(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundDangerousProps();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isPermissiveSelinux(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isPermissiveSelinux();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isSuExists(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isSuExists();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isAccessedSuperuserApk(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isAccessedSuperuserApk();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundSuBinary(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundSuBinary();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundBusyboxBinary(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundBusyboxBinary();
}


JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundXposed(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundXposed();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundResetprop(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundResetprop();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundWrongPathPermission(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundWrongPathPermission();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundHooks(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundHooks();
}

constants:

// Comma-separated tags describing the build, like= "unsigned,debug".
const char *const ANDROID_OS_BUILD_TAGS = "ro.build.tags";

// A string that uniquely identifies this build. 'BRAND/PRODUCT/DEVICE:RELEASE/ID/VERSION.INCREMENTAL:TYPE/TAGS'.
const char *const ANDROID_OS_BUILD_FINGERPRINT = "ro.build.fingerprint";

const char *const ANDROID_OS_SECURE = "ro.secure";

const char *const ANDROID_OS_DEBUGGABLE = "ro.debuggable";
const char *const ANDROID_OS_SYS_INITD = "sys.initd";
const char *const ANDROID_OS_BUILD_SELINUX = "ro.build.selinux";
//see https://android.googlesource.com/platform/system/core/+/master/adb/services.cpp#86
const char *const SERVICE_ADB_ROOT = "service.adb.root";

const char * const MG_SU_PATH[] = {
        "/data/local/",
        "/data/local/bin/",
        "/data/local/xbin/",
        "/sbin/",
        "/system/bin/",
        "/system/bin/.ext/",
        "/system/bin/failsafe/",
        "/system/sd/xbin/",
        "/su/xbin/",
        "/su/bin/",
        "/magisk/.core/bin/",
        "/system/usr/we-need-root/",
        "/system/xbin/",
        0
};

const char * const MG_EXPOSED_FILES[] = {
        "/system/lib/libxposed_art.so",
        "/system/lib64/libxposed_art.so",
        "/system/xposed.prop",
        "/cache/recovery/xposed.zip",
        "/system/framework/XposedBridge.jar",
        "/system/bin/app_process64_xposed",
        "/system/bin/app_process32_xposed",
        "/magisk/xposed/system/lib/libsigchain.so",
        "/magisk/xposed/system/lib/libart.so",
        "/magisk/xposed/system/lib/libart-disassembler.so",
        "/magisk/xposed/system/lib/libart-compiler.so",
        "/system/bin/app_process32_orig",
        "/system/bin/app_process64_orig",
        0
};

const char * const MG_READ_ONLY_PATH[] = {
        "/system",
        "/system/bin",
        "/system/sbin",
        "/system/xbin",
        "/vendor/bin",
        "/sbin",
        "/etc",
        0
};

root detections from native code:

struct mntent *getMntent(FILE *fp, struct mntent *e, char *buf, int buf_len) {

    while (fgets(buf, buf_len, fp) != NULL) {
        // Entries look like "/dev/block/vda /system ext4 ro,seclabel,relatime,data=ordered 0 0".
        // That is: mnt_fsname mnt_dir mnt_type mnt_opts mnt_freq mnt_passno.
        int fsname0, fsname1, dir0, dir1, type0, type1, opts0, opts1;
        if (sscanf(buf, " %n%*s%n %n%*s%n %n%*s%n %n%*s%n %d %d",
                   &fsname0, &fsname1, &dir0, &dir1, &type0, &type1, &opts0, &opts1,
                   &e->mnt_freq, &e->mnt_passno) == 2) {
            e->mnt_fsname = &buf[fsname0];
            buf[fsname1] = '\0';
            e->mnt_dir = &buf[dir0];
            buf[dir1] = '\0';
            e->mnt_type = &buf[type0];
            buf[type1] = '\0';
            e->mnt_opts = &buf[opts0];
            buf[opts1] = '\0';
            return e;
        }
    }
    return NULL;
}


bool isPresentMntOpt(const struct mntent *pMnt, const char *pOpt) {
    char *token = pMnt->mnt_opts;
    const char *end = pMnt->mnt_opts + strlen(pMnt->mnt_opts);
    const size_t optLen = strlen(pOpt);
    while (token != NULL) {
        const char *tokenEnd = token + optLen;
        if (tokenEnd > end) break;
        if (memcmp(token, pOpt, optLen) == 0 &&
            (*tokenEnd == '\0' || *tokenEnd == ',' || *tokenEnd == '=')) {
            return true;
        }
        token = strchr(token, ',');
        if (token != NULL) {
            token++;
        }
    }
    return false;
}

static char *concat2str(const char *pString1, const char *pString2) {
    char *result;
    size_t lengthBuffer = 0;

    lengthBuffer = strlen(pString1) +
                   strlen(pString2) + 1;
    result = malloc(lengthBuffer);
    if (result == NULL) {
        GR_LOGW("malloc failed\n");
        return NULL;
    }
    memset(result, 0, lengthBuffer);
    strcpy(result, pString1);
    strcat(result, pString2);
    return result;
}

static bool
isBadPropertyState(const char *key, const char *badValue, bool isObligatoryProperty, bool isExact) {
    if (badValue == NULL) {
        GR_LOGE("badValue may not be NULL");
        return false;
    }
    if (key == NULL) {
        GR_LOGE("key may not be NULL");
        return false;
    }
    char value[PROP_VALUE_MAX + 1];
    int length = __system_property_get(key, value);
    bool result = false;
    /* A length 0 value indicates that the property is not defined */
    if (length > 0) {
        GR_LOGI("property:[%s]==[%s]", key, value);
        if (isExact) {
            if (strcmp(value, badValue) == 0) {
                GR_LOGW("bad value[%s] equals to [%s] in the property [%s]", value, badValue, key);
                result = true;
            }
        } else {
            if (strlen(value) >= strlen(badValue) && strstr(value, badValue) != NULL) {
                GR_LOGW("bad value[%s] found in [%s] in the property [%s]", value, badValue, key);
                result = true;
            }
        }
    } else {
        GR_LOGI("[%s] property not found", key);
        if (isObligatoryProperty) {
            result = true;
        }
    }
    return result;
}

bool isDetectedTestKeys() {
    const char *TEST_KEYS_VALUE = "test-keys";
    return isBadPropertyState(ANDROID_OS_BUILD_TAGS, TEST_KEYS_VALUE, true, false);
}

bool isDetectedDevKeys() {
    const char *DEV_KEYS_VALUE = "dev-keys";
    return isBadPropertyState(ANDROID_OS_BUILD_TAGS, DEV_KEYS_VALUE, true, false);
}

bool isNotFoundReleaseKeys() {
    const char *RELEASE_KEYS_VALUE = "release-keys";
    return !isBadPropertyState(ANDROID_OS_BUILD_TAGS, RELEASE_KEYS_VALUE, false, true);
}

bool isFoundWrongPathPermission() {

    bool result = false;
    FILE *file = fopen("/proc/mounts", "r");
    char mntent_strings[BUFSIZ];
    if (file == NULL) {
        GR_LOGE("setmntent");
        return result;
    }

    struct mntent ent = {0};
    while (NULL != getMntent(file, &ent, mntent_strings, sizeof(mntent_strings))) {
        for (size_t i = 0; MG_READ_ONLY_PATH[i]; i++) {
            if (strcmp((&ent)->mnt_dir, MG_READ_ONLY_PATH[i]) == 0 &&
                isPresentMntOpt(&ent, "rw")) {
                GR_LOGI("%s %s %s %s\n", (&ent)->mnt_fsname, (&ent)->mnt_dir, (&ent)->mnt_opts,
                        (&ent)->mnt_type);
                result = true;
                break;
            }
        }
        memset(&ent, 0, sizeof(ent));
    }
    fclose(file);
    return result;
}


bool isFoundDangerousProps() {
    const char *BAD_DEBUGGABLE_VALUE = "1";
    const char *BAD_SECURE_VALUE = "0";
    const char *BAD_SYS_INITD_VALUE = "1";
    const char *BAD_SERVICE_ADB_ROOT_VALUE = "1";

    bool result = isBadPropertyState(ANDROID_OS_DEBUGGABLE, BAD_DEBUGGABLE_VALUE, true, true) ||
                  isBadPropertyState(SERVICE_ADB_ROOT, BAD_SERVICE_ADB_ROOT_VALUE, false, true) ||
                  isBadPropertyState(ANDROID_OS_SECURE, BAD_SECURE_VALUE, true, true) ||
                  isBadPropertyState(ANDROID_OS_SYS_INITD, BAD_SYS_INITD_VALUE, false, true);

    return result;
}

bool isPermissiveSelinux() {
    const char *BAD_VALUE = "0";
    return isBadPropertyState(ANDROID_OS_BUILD_SELINUX, BAD_VALUE, false, false);
}

bool isSuExists() {
    char buf[BUFSIZ];
    char *str = NULL;
    char *temp = NULL;
    size_t size = 1;  // start with size of 1 to make room for null terminator
    size_t strlength;

    FILE *pipe = popen("which su", "r");
    if (pipe == NULL) {
        GR_LOGI("pipe is null");
        return false;
    }

    while (fgets(buf, sizeof(buf), pipe) != NULL) {
        strlength = strlen(buf);
        temp = realloc(str, size + strlength);  // allocate room for the buf that gets appended
        if (temp == NULL) {
            // allocation error
            GR_LOGE("Error (re)allocating memory");
            pclose(pipe);
            if (str != NULL) {
                free(str);
            }
            return false;
        } else {
            str = temp;
        }
        strcpy(str + size - 1, buf);
        size += strlength;
    }
    pclose(pipe);
    GR_LOGW("A size of the result from pipe is [%zu], result:\n [%s] ", size, str);
    if (str != NULL) {
        free(str);
    }
    return size > 1 ? true : false;
}

static bool isAccessedFile(const char *path) {
    int result = access(path, F_OK);
    GR_LOGV("[%s] has been accessed with result: [%d]", path, result);
    return result == 0 ? true : false;
}

static bool isFoundBinaryFromArray(const char *const *array, const char *binary) {
    for (size_t i = 0; array[i]; ++i) {
        char *checkedPath = concat2str(array[i], binary);
        if (checkedPath == NULL) { // malloc failed
            return false;
        }
        bool result = isAccessedFile(checkedPath);
        free(checkedPath);
        if (result) {
            return result;
        }
    }
    return false;
}

bool isAccessedSuperuserApk() {
    return isAccessedFile("/system/app/Superuser.apk");
}

bool isFoundResetprop() {
    return isAccessedFile("/data/magisk/resetprop");
}

bool isFoundSuBinary() {
    return isFoundBinaryFromArray(MG_SU_PATH, "su");
}

bool isFoundBusyboxBinary() {
    return isFoundBinaryFromArray(MG_SU_PATH, "busybox");
}

bool isFoundXposed() {
    for (size_t i = 0; MG_EXPOSED_FILES[i]; ++i) {
        bool result = isAccessedFile(MG_EXPOSED_FILES[i]);
        if (result) {
            return result;
        }
    }
    return false;
}

bool isFoundHooks() {
    bool result = false;
    pid_t pid = getpid();
    char maps_file_name[512];
    sprintf(maps_file_name, "/proc/%d/maps", pid);
    GR_LOGI("try to open [%s]", maps_file_name);
    const size_t line_size = BUFSIZ;
    char *line = malloc(line_size);
    if (line == NULL) {
        return result;
    }
    FILE *fp = fopen(maps_file_name, "r");
    if (fp == NULL) {
        free(line);
        return result;
    }
    memset(line, 0, line_size);
    const char *substrate = "com.saurik.substrate";
    const char *xposed = "XposedBridge.jar";
    while (fgets(line, line_size, fp) != NULL) {
        const size_t real_line_size = strlen(line);
        if ((real_line_size >= strlen(substrate) && strstr(line, substrate) != NULL) ||
            (real_line_size >= strlen(xposed) && strstr(line, xposed) != NULL)) {
            GR_LOGI("found in [%s]: [%s]", maps_file_name, line);
            result = true;
            break;
        }
    }
    free(line);
    fclose(fp);
    return result;
}

Creating email templates with Django

send_emai() didn't work for me so I used EmailMessage here in django docs.

I have included two versions of the anser:

  1. With html email version only
  2. With plain text email and html email versions
from django.template.loader import render_to_string 
from django.core.mail import EmailMessage

# import file with html content
html_version = 'path/to/html_version.html'

html_message = render_to_string(html_version, { 'context': context, })

message = EmailMessage(subject, html_message, from_email, [to_email])
message.content_subtype = 'html' # this is required because there is no plain text email version
message.send()

If you want to include a plain text version of your email, modify the above like this:

from django.template.loader import render_to_string 
from django.core.mail import EmailMultiAlternatives # <= EmailMultiAlternatives instead of EmailMessage

plain_version = 'path/to/plain_version.html' # import plain version. No html content
html_version = 'path/to/html_version.html' # import html version. Has html content

plain_message = render_to_string(plain_version, { 'context': context, })
html_message = render_to_string(html_version, { 'context': context, })

message = EmailMultiAlternatives(subject, plain_message, from_email, [to_email])
message.attach_alternative(html_message, "text/html") # attach html version
message.send()

My plain and html versions look like this: plain_version.html:

Plain text {{ context }}

html_version.html

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
 <head>
 ...
 </head>
<body>
<table align="center" border="0" cellpadding="0" cellspacing="0" width="320" style="border: none; border-collapse: collapse; font-family:  Arial, sans-serif; font-size: 14px; line-height: 1.5;">
...
{{ context }}
...
</table>
</body>
</html>

ViewDidAppear is not called when opening app from background

Curious about the exact sequence of events, I instrumented an app as follows: (@Zohaib, you can use the NSNotificationCenter code below to answer your question).

// AppDelegate.m

- (void)applicationWillEnterForeground:(UIApplication *)application
{
    NSLog(@"app will enter foreground");
}

- (void)applicationDidBecomeActive:(UIApplication *)application
{
    NSLog(@"app did become active");
}

// ViewController.m

- (void)viewDidLoad
{
    [super viewDidLoad];
    NSLog(@"view did load");

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(appDidBecomeActive:) name:UIApplicationDidBecomeActiveNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(appWillEnterForeground:) name:UIApplicationWillEnterForegroundNotification object:nil];
}

- (void)appDidBecomeActive:(NSNotification *)notification {
    NSLog(@"did become active notification");
}

- (void)appWillEnterForeground:(NSNotification *)notification {
    NSLog(@"will enter foreground notification");
}

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    NSLog(@"view will appear");
}

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
    NSLog(@"view did appear");
}

At launch, the output looks like this:

2013-04-07 09:31:06.505 myapp[15459:11303] view did load
2013-04-07 09:31:06.507 myapp[15459:11303] view will appear
2013-04-07 09:31:06.511 myapp[15459:11303] app did become active
2013-04-07 09:31:06.512 myapp[15459:11303] did become active notification
2013-04-07 09:31:06.517 myapp[15459:11303] view did appear

Enter the background then reenter the foreground:

2013-04-07 09:32:05.923 myapp[15459:11303] app will enter foreground
2013-04-07 09:32:05.924 myapp[15459:11303] will enter foreground notification
2013-04-07 09:32:05.925 myapp[15459:11303] app did become active
2013-04-07 09:32:05.926 myapp[15459:11303] did become active notification

How to draw a filled triangle in android canvas?

You need remove path.moveTo after first initial.

Path path = new Path();
path.moveTo(point1_returned.x, point1_returned.y);
path.lineTo(point2_returned.x, point2_returned.y);
path.lineTo(point3_returned.x, point3_returned.y);
path.lineTo(point1_returned.x, point1_returned.y);
path.close();

Use LINQ to get items in one List<>, that are not in another List<>

If you override the equality of People then you can also use:

peopleList2.Except(peopleList1)

Except should be significantly faster than the Where(...Any) variant since it can put the second list into a hashtable. Where(...Any) has a runtime of O(peopleList1.Count * peopleList2.Count) whereas variants based on HashSet<T> (almost) have a runtime of O(peopleList1.Count + peopleList2.Count).

Except implicitly removes duplicates. That shouldn't affect your case, but might be an issue for similar cases.

Or if you want fast code but don't want to override the equality:

var excludedIDs = new HashSet<int>(peopleList1.Select(p => p.ID));
var result = peopleList2.Where(p => !excludedIDs.Contains(p.ID));

This variant does not remove duplicates.

How to return temporary table from stored procedure

A temp table can be created in the caller and then populated from the called SP.

  create table #GetValuesOutputTable(
     ...   
  );

  exec GetValues; -- populates #GetValuesOutputTable

  select * from #GetValuesOutputTable;

Some advantages of this approach over the "insert exec" is that it can be nested and that it can be used as input or output.

Some disadvantages are that the "argument" is not public, the table creation exists within each caller, and that the name of the table could collide with other temp objects. It helps when the temp table name closely matches the SP name and follows some convention.

Taking it a bit farther, for output only temp tables, the insert-exec approach and the temp table approach can be supported simultaneously by the called SP. This doesn't help too much for chaining SP's because the table still need to be defined in the caller but can help to simplify testing from the cmd line or when calling externally.

  -- The "called" SP
  declare
      @returnAsSelect bit = 0;

  if object_id('tempdb..#GetValuesOutputTable') is null
  begin
      set @returnAsSelect = 1;
      create table #GetValuesOutputTable(
         ...   
      );
  end

  -- populate the table

  if @returnAsSelect = 1
      select * from #GetValuesOutputTable;

PHP/MySQL insert row then get 'id'

An example.

    $query_new = "INSERT INTO students(courseid, coursename) VALUES ('', ?)";
    $query_new = $databaseConnection->prepare($query_new);
    $query_new->bind_param('s', $_POST['coursename']);
    $query_new->execute();
    $course_id = $query_new->insert_id;
    $query_new->close();

The code line $course_id = $query_new->insert_id; will display the ID of the last inserted row. Hope this helps.

What is the difference between the float and integer data type when the size is the same?

  • float stores floating-point values, that is, values that have potential decimal places
  • int only stores integral values, that is, whole numbers

So while both are 32 bits wide, their use (and representation) is quite different. You cannot store 3.141 in an integer, but you can in a float.

Dissecting them both a little further:

In an integer, all bits are used to store the number value. This is (in Java and many computers too) done in the so-called two's complement. This basically means that you can represent the values of −231 to 231 − 1.

In a float, those 32 bits are divided between three distinct parts: The sign bit, the exponent and the mantissa. They are laid out as follows:

S EEEEEEEE MMMMMMMMMMMMMMMMMMMMMMM

There is a single bit that determines whether the number is negative or non-negative (zero is neither positive nor negative, but has the sign bit set to zero). Then there are eight bits of an exponent and 23 bits of mantissa. To get a useful number from that, (roughly) the following calculation is performed:

M × 2E

(There is more to it, but this should suffice for the purpose of this discussion)

The mantissa is in essence not much more than a 24-bit integer number. This gets multiplied by 2 to the power of the exponent part, which, roughly, is a number between −128 and 127.

Therefore you can accurately represent all numbers that would fit in a 24-bit integer but the numeric range is also much greater as larger exponents allow for larger values. For example, the maximum value for a float is around 3.4 × 1038 whereas int only allows values up to 2.1 × 109.

But that also means, since 32 bits only have 4.2 × 109 different states (which are all used to represent the values int can store), that at the larger end of float's numeric range the numbers are spaced wider apart (since there cannot be more unique float numbers than there are unique int numbers). You cannot represent some numbers exactly, then. For example, the number 2 × 1012 has a representation in float of 1,999,999,991,808. That might be close to 2,000,000,000,000 but it's not exact. Likewise, adding 1 to that number does not change it because 1 is too small to make a difference in the larger scales float is using there.

Similarly, you can also represent very small numbers (between 0 and 1) in a float but regardless of whether the numbers are very large or very small, float only has a precision of around 6 or 7 decimal digits. If you have large numbers those digits are at the start of the number (e.g. 4.51534 × 1035, which is nothing more than 451534 follows by 30 zeroes – and float cannot tell anything useful about whether those 30 digits are actually zeroes or something else), for very small numbers (e.g. 3.14159 × 10−27) they are at the far end of the number, way beyond the starting digits of 0.0000...

How to capture no file for fs.readFileSync()?

I use an immediately invoked lambda for these scenarios:

const config = (() => {
  try {
    return JSON.parse(fs.readFileSync('config.json'));
  } catch (error) {
    return {};
  }
})();

async version:

const config = await (async () => {
  try {
    return JSON.parse(await fs.readFileAsync('config.json'));
  } catch (error) {
    return {};
  }
})();

Calling onclick on a radiobutton list using javascript

I agree with @annakata that this question needs some more clarification, but here is a very, very basic example of how to setup an onclick event handler for the radio buttons:

<html>
 <head>
  <script type="text/javascript">
    window.onload = function() {

        var ex1 = document.getElementById('example1');
        var ex2 = document.getElementById('example2');
        var ex3 = document.getElementById('example3');

        ex1.onclick = handler;
        ex2.onclick = handler;
        ex3.onclick = handler;

    }

    function handler() {
        alert('clicked');
    }
  </script>
 </head>
 <body>
  <input type="radio" name="example1" id="example1" value="Example 1" />
  <label for="example1">Example 1</label>
  <input type="radio" name="example2" id="example2" value="Example 2" />
  <label for="example1">Example 2</label>
  <input type="radio" name="example3" id="example3" value="Example 3" />
  <label for="example1">Example 3</label>
 </body>
</html>

Hibernate dialect for Oracle Database 11g?

According to supported databases, Oracle 11g is not officially supported. Although, I believe you shouldn't have any problems using org.hibernate.dialect.OracleDialect.

Angular, content type is not being sent with $http

Great! The solution given above worked for me. Had the same problem with a GET call.

 method: 'GET',
 data: '',
 headers: {
        "Content-Type": "application/json"
 }

How do I kill all the processes in Mysql "show processlist"?

Or... in shell...

service mysql restart

Yeah, I know, I'm lazy, but it can be handy too.

Appending the same string to a list of strings in Python

list2 = ['%sbar' % (x,) for x in list]

And don't use list as a name; it shadows the built-in type.

How to call a PHP file from HTML or Javascript

You just need to post the form data to the insert php file function, see below :)

class DbConnect
{
// Database login vars
private $dbHostname = '';
private $dbDatabase = '';
private $dbUsername = '';
private $dbPassword = '';
public $db = null;

public function connect()
{

    try
    {
        $this->db = new PDO("mysql:host=".$this->dbHostname.";dbname=".$this->dbDatabase, $this->dbUsername, $this->dbPassword);
        $this->db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    }
    catch(PDOException $e)
    {
        echo "It seems there was an error.  Please refresh your browser and try again. ".$e->getMessage();
    }
}

public function store($email)
{
    $stm = $this->db->prepare('INSERT INTO subscribers (email) VALUES ?');
    $stm->bindValue(1, $email);

    return $stm->execute();
}
}

How can I get the average (mean) of selected columns

Try using rowMeans:

z$mean=rowMeans(z[,c("x", "y")], na.rm=TRUE)

  w x  y mean
1 5 1  1    1
2 6 2  2    2
3 7 3  3    3
4 8 4 NA    4

How to grey out a button?

All given answers work fine, but I remember learning that using setAlpha can be a bad idea performance wise (more info here). So creating a StateListDrawable is a better idea to manage disabled state of buttons. Here's how:

Create a XML btn_blue.xml in res/drawable folder:

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <!-- Disable background -->
    <item android:state_enabled="false"
          android:color="@color/md_blue_200"/>
    
    <!-- Enabled background -->
    <item android:color="@color/md_blue_500"/>
</selector>

Create a button style in res/values/styles.xml

<style name="BlueButton" parent="ThemeOverlay.AppCompat">
      <item name="colorButtonNormal">@drawable/btn_blue</item>
      <item name="android:textColor">@color/md_white_1000</item>
</style>

Then apply this style to your button:

<Button
     android:id="@+id/my_disabled_button"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:theme="@style/BlueButton"/>

Now when you call btnBlue.setEnabled(true) OR btnBlue.setEnabled(false) the state colors will automatically switch.

Kubernetes pod gets recreated when deleted

I experienced a similar problem: after deleting the deployment (kubectl delete deploy <name>), the pods kept "Running" and where automatically re-created after deletion (kubectl delete po <name>).

It turned out that the associated replica set was not deleted automatically for some reason, and after deleting that (kubectl delete rs <name>), it was possible to delete the pods.

ORA-00904: invalid identifier

I had the same exception in JPA 2 using eclipse link. I had an @embedded class with one to one relationship with an entity. By mistake ,in the embedded class, i had also the annotation @Table("TRADER"). When the DB was created by the JPA from the entities it also created a table TRADER (which was a wrong as the Trader entity was embedded to the main entity) and the existence of that table was causing the above exception every time i was trying to persist my entity. After deleting the TRADER table the exception disappered.

Java, How to specify absolute value and square roots

Use the java.lang.Math class, and specifically for absolute value and square root:, the abs() and sqrt() methods.

jquery drop down menu closing by clicking outside

how to have a click event outside of the dropdown menu so that it close the dropdown menu ? Heres the code

$(document).click(function (e) {
    e.stopPropagation();
    var container = $(".dropDown");

    //check if the clicked area is dropDown or not
    if (container.has(e.target).length === 0) {
        $('.subMenu').hide();
    }
})

Java - escape string to prevent SQL injection

After searching an testing alot of solution for prevent sqlmap from sql injection, in case of legacy system which cant apply prepared statments every where.

java-security-cross-site-scripting-xss-and-sql-injection topic WAS THE SOLUTION

i tried @Richard s solution but did not work in my case. i used a filter

The goal of this filter is to wrapper the request into an own-coded wrapper MyHttpRequestWrapper which transforms:

the HTTP parameters with special characters (<, >, ‘, …) into HTML codes via the org.springframework.web.util.HtmlUtils.htmlEscape(…) method. Note: There is similar classe in Apache Commons : org.apache.commons.lang.StringEscapeUtils.escapeHtml(…) the SQL injection characters (‘, “, …) via the Apache Commons classe org.apache.commons.lang.StringEscapeUtils.escapeSql(…)

<filter>
<filter-name>RequestWrappingFilter</filter-name>
<filter-class>com.huo.filter.RequestWrappingFilter</filter-class>
</filter>

<filter-mapping>
<filter-name>RequestWrappingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>




package com.huo.filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletReponse;
import javax.servlet.http.HttpServletRequest;

public class RequestWrappingFilter implements Filter{

    public void doFilter(ServletRequest req, ServletReponse res, FilterChain chain) throws IOException, ServletException{
        chain.doFilter(new MyHttpRequestWrapper(req), res);
    }

    public void init(FilterConfig config) throws ServletException{
    }

    public void destroy() throws ServletException{
    }
}




package com.huo.filter;

import java.util.HashMap;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

import org.apache.commons.lang.StringEscapeUtils;

public class MyHttpRequestWrapper extends HttpServletRequestWrapper{
    private Map<String, String[]> escapedParametersValuesMap = new HashMap<String, String[]>();

    public MyHttpRequestWrapper(HttpServletRequest req){
        super(req);
    }

    @Override
    public String getParameter(String name){
        String[] escapedParameterValues = escapedParametersValuesMap.get(name);
        String escapedParameterValue = null; 
        if(escapedParameterValues!=null){
            escapedParameterValue = escapedParameterValues[0];
        }else{
            String parameterValue = super.getParameter(name);

            // HTML transformation characters
            escapedParameterValue = org.springframework.web.util.HtmlUtils.htmlEscape(parameterValue);

            // SQL injection characters
            escapedParameterValue = StringEscapeUtils.escapeSql(escapedParameterValue);

            escapedParametersValuesMap.put(name, new String[]{escapedParameterValue});
        }//end-else

        return escapedParameterValue;
    }

    @Override
    public String[] getParameterValues(String name){
        String[] escapedParameterValues = escapedParametersValuesMap.get(name);
        if(escapedParameterValues==null){
            String[] parametersValues = super.getParameterValues(name);
            escapedParameterValue = new String[parametersValues.length];

            // 
            for(int i=0; i<parametersValues.length; i++){
                String parameterValue = parametersValues[i];
                String escapedParameterValue = parameterValue;

                // HTML transformation characters
                escapedParameterValue = org.springframework.web.util.HtmlUtils.htmlEscape(parameterValue);

                // SQL injection characters
                escapedParameterValue = StringEscapeUtils.escapeSql(escapedParameterValue);

                escapedParameterValues[i] = escapedParameterValue;
            }//end-for

            escapedParametersValuesMap.put(name, escapedParameterValues);
        }//end-else

        return escapedParameterValues;
    }
}

How to select a single field for all documents in a MongoDB collection?

db.<collection>.find({}, {field1: <value>, field2: <value> ...})

In your example, you can do something like:

db.students.find({}, {"roll":true, "_id":false})

Projection

The projection parameter determines which fields are returned in the matching documents. The projection parameter takes a document of the following form:

{ field1: <value>, field2: <value> ... }
The <value> can be any of the following:
  1. 1 or true to include the field in the return documents.

  2. 0 or false to exclude the field.

NOTE

For the _id field, you do not have to explicitly specify _id: 1 to return the _id field. The find() method always returns the _id field unless you specify _id: 0 to suppress the field.

READ MORE

How to get the list of all database users

Whenever you 'see' something in the GUI (SSMS) and you're like "that's what I need", you can always run Sql Profiler to fish for the query that was used.

Run Sql Profiler. Attach it to your database of course.

Then right click in the GUI (in SSMS) and click "Refresh".
And then go see what Profiler "catches".

I got the below when I was in MyDatabase / Security / Users and clicked "refresh" on the "Users".

Again, I didn't come up with the WHERE clause and the LEFT OUTER JOIN, it was a part of the SSMS query. And this query is something that somebody at Microsoft has written (you know, the peeps who know the product inside and out, aka, the experts), so they are familiar with all the weird "flags" in the database.

But the SSMS/GUI -> Sql Profiler tricks works in many scenarios.

SELECT
u.name AS [Name],
'Server[@Name=' + quotename(CAST(
        serverproperty(N'Servername')
       AS sysname),'''') + ']' + '/Database[@Name=' + quotename(db_name(),'''') + ']' + '/User[@Name=' + quotename(u.name,'''') + ']' AS [Urn],
u.create_date AS [CreateDate],
u.principal_id AS [ID],
CAST(CASE dp.state WHEN N'G' THEN 1 WHEN 'W' THEN 1 ELSE 0 END AS bit) AS [HasDBAccess]
FROM
sys.database_principals AS u
LEFT OUTER JOIN sys.database_permissions AS dp ON dp.grantee_principal_id = u.principal_id and dp.type = 'CO'
WHERE
(u.type in ('U', 'S', 'G', 'C', 'K' ,'E', 'X'))
ORDER BY
[Name] ASC

Image comparison - fast algorithm

Picking 100 random points could mean that similar (or occasionally even dissimilar) images would be marked as the same, which I assume is not what you want. MD5 hashes wouldn't work if the images were different formats (png, jpeg, etc), had different sizes, or had different metadata. Reducing all images to a smaller size is a good bet, doing a pixel-for- pixel comparison shouldn't take too long as long as you're using a good image library / fast language, and the size is small enough.

You could try making them tiny, then if they are the same perform another comparison on a larger size - could be a good combination of speed and accuracy...

Getting the class name from a static method in Java

In order to support refactoring correctly (rename class), then you should use either:

 MyClass.class.getName(); // full name with package

or (thanks to @James Van Huis):

 MyClass.class.getSimpleName(); // class name and no more

AJAX jQuery refresh div every 5 seconds

you can use this one.

<div id="test"></div>

you java script code should be like that.

setInterval(function(){
      $('#test').load('test.php');
 },5000);

Angular 4.3 - HttpClient set params

Before 5.0.0-beta.6

let httpParams = new HttpParams();
Object.keys(data).forEach(function (key) {
     httpParams = httpParams.append(key, data[key]);
});

Since 5.0.0-beta.6

Since 5.0.0-beta.6 (2017-09-03) they added new feature (accept object map for HttpClient headers & params)

Going forward the object can be passed directly instead of HttpParams.

getCountries(data: any) {
    // We don't need any more these lines
    // let httpParams = new HttpParams();
    // Object.keys(data).forEach(function (key) {
    //     httpParams = httpParams.append(key, data[key]);
    // });

    return this.httpClient.get("/api/countries", {params: data})
}

Why Git is not allowing me to commit even after configuration?

Do you have a local user.name or user.email that's overriding the global one?

git config --list --global | grep user
  user.name=YOUR NAME
  user.email=YOUR@EMAIL
git config --list --local | grep user
  user.name=YOUR NAME
  user.email=

If so, remove them

git config --unset --local user.name
git config --unset --local user.email

The local settings are per-clone, so you'll have to unset the local user.name and user.email for each of the repos on your machine.

How to input matrix (2D list) in Python?

a,b=[],[]
n=int(input("Provide me size of squre matrix row==column : "))
for i in range(n):
   for j in range(n):
      b.append(int(input()))
    a.append(b)
    print("Here your {} column {}".format(i+1,a))
    b=[]
for m in range(n):
    print(a[m])

works perfectly

How to select lines between two marker patterns which may occur multiple times with awk/sed

something like this works for me:

file.awk:

BEGIN {
    record=0
}

/^abc$/ {
    record=1
}

/^mno$/ {
    record=0;
    print "s="s;
    s=""
}

!/^abc|mno$/ {
    if (record==1) {
        s = s"\n"$0
    }   
}

using: awk -f file.awk data...

edit: O_o fedorqui solution is way better/prettier than mine.

URL encoding in Android

For android, I would use String android.net.Uri.encode(String s)

Encodes characters in the given string as '%'-escaped octets using the UTF-8 scheme. Leaves letters ("A-Z", "a-z"), numbers ("0-9"), and unreserved characters ("_-!.~'()*") intact. Encodes all other characters.

Ex/

String urlEncoded = "http://stackoverflow.com/search?q=" + Uri.encode(query);

Remove HTML tags from a String

Here is one more variant of how to replace all(HTML Tags | HTML Entities | Empty Space in HTML content)

content.replaceAll("(<.*?>)|(&.*?;)|([ ]{2,})", ""); where content is a String.

How to update/refresh specific item in RecyclerView

That's also my last problem. Here my solution I use data Model and adapter for my RecyclerView

 /*Firstly, register your new data to your model*/
 DataModel detail = new DataModel(id, name, sat, image);

 /*after that, use set to replace old value with the new one*/
 int index = 4;
 mData.set(index, detail);

 /*finally, refresh your adapter*/
 if(adapter!=null)
    adapter.notifyItemChanged(index);

Can I draw rectangle in XML?

try this

                <TableRow
                    android:layout_width="match_parent"
                    android:layout_marginTop="5dp"
                    android:layout_height="wrap_content">

                    <View
                        android:layout_width="15dp"
                        android:layout_height="15dp"
                        android:background="#3fe1fa" />

                    <TextView
                        android:textSize="12dp"
                        android:paddingLeft="10dp"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:textAppearance="?android:attr/textAppearanceMedium"
                        android:text="1700 Market Street"
                        android:id="@+id/textView8" />
                </TableRow>

output

enter image description here

Bad Gateway 502 error with Apache mod_proxy and Tomcat

you should be able to get this problem resolved through a timeout and proxyTimeout parameter set to 600 seconds. It worked for me after battling for a while.

Could not find folder 'tools' inside SDK

If I get you correctly you have just downloaded Android sdk and want to configure it working with Eclipse. I think you miss one step from the installation of the sdk:
1) you download it
2) you extract it somewhere
3) then go to the specified directory and start AndroidManager (or was it just android??). There you specify you need platform-tools and the manager will configure that for you. This will also provide you with the 'adb' executable which is crucial for the Android developement.

After that you install ADT (which I think you already did) and from Eclipse preferences -> Android options you get a place to specify where your android-sdk is. If you specify it after you did the 'step 3' you should be good to go.

I am not 100% sure I got it correctly and what your state is, so please forgive me if my comment is irrelevant. If I am wrong I will be happy to help if you provide some more details.

Something I am completely sure is that you shouldn't need to create the folder 'tools' by yourself.

PS: The description I gave is for newer versions of android sdk, but if you are encountering a problem with older version I will recommend you to start from scratch with newer version. It shouldn't take you that long time.

Can anyone explain IEnumerable and IEnumerator to me?

IEnumerable implements GetEnumerator. When called, that method will return an IEnumerator which implements MoveNext, Reset and Current.

Thus when your class implements IEnumerable, you are saying that you can call a method (GetEnumerator) and get a new object returned (an IEnumerator) you can use in a loop such as foreach.

Functional, Declarative, and Imperative Programming

In a nutshell:

An imperative language specfies a series of instructions that the computer executes in sequence (do this, then do that).

A declarative language declares a set of rules about what outputs should result from which inputs (eg. if you have A, then the result is B). An engine will apply these rules to inputs, and give an output.

A functional language declares a set of mathematical/logical functions which define how input is translated to output. eg. f(y) = y * y. it is a type of declarative language.

What is the equivalent of Java's final in C#?

Java class final and method final -> sealed. Java member variable final -> readonly for runtime constant, const for compile time constant.

No equivalent for Local Variable final and method argument final

using CASE in the WHERE clause

You can transform logical implication A => B to NOT A or B. This is one of the most basic laws of logic. In your case it is something like this:

SELECT *
FROM logs 
WHERE pw='correct' AND (id>=800 OR success=1)  
AND YEAR(timestamp)=2011

I also transformed NOT id<800 to id>=800, which is also pretty basic.

How to access property of anonymous type in C#?

If you're storing the object as type object, you need to use reflection. This is true of any object type, anonymous or otherwise. On an object o, you can get its type:

Type t = o.GetType();

Then from that you look up a property:

PropertyInfo p = t.GetProperty("Foo");

Then from that you can get a value:

object v = p.GetValue(o, null);

This answer is long overdue for an update for C# 4:

dynamic d = o;
object v = d.Foo;

And now another alternative in C# 6:

object v = o?.GetType().GetProperty("Foo")?.GetValue(o, null);

Note that by using ?. we cause the resulting v to be null in three different situations!

  1. o is null, so there is no object at all
  2. o is non-null but doesn't have a property Foo
  3. o has a property Foo but its real value happens to be null.

So this is not equivalent to the earlier examples, but may make sense if you want to treat all three cases the same.

How to use find command to find all files with extensions from list?

find -E /path/to -regex ".*\.(jpg|gif|png|jpeg)" > log

The -E saves you from having to escape the parens and pipes in your regex.

How to check if a network port is open on linux?

Agree with Sachin. Just one improvement, use connect_ex instead of connect, which can avoid try except

>>> def port_check(ip_port):
...     s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
...     s.settimeout(1)
...     r = s.connect_ex(ip_port)
...     return r == 0
... 
>>> port_check(loc)
True
>>> port_check(loc_x)
False
>>> loc
('10.3.157.24', 6443)
>>> 

Empty ArrayList equals null

No, because it contains items there must be an instance of it. Its items being null is irrelevant, so the statment ((arrayList) != null) == true

Check date with todays date

public static boolean itIsToday(long date){
    boolean result = false;
    try{
        Calendar calendarData = Calendar.getInstance();
        calendarData.setTimeInMillis(date);
        calendarData.set(Calendar.HOUR_OF_DAY, 0);
        calendarData.set(Calendar.MINUTE, 0);
        calendarData.set(Calendar.SECOND, 0);
        calendarData.set(Calendar.MILLISECOND, 0);

        Calendar calendarToday = Calendar.getInstance();
        calendarToday.setTimeInMillis(System.currentTimeMillis());
        calendarToday.set(Calendar.HOUR_OF_DAY, 0);
        calendarToday.set(Calendar.MINUTE, 0);
        calendarToday.set(Calendar.SECOND, 0);
        calendarToday.set(Calendar.MILLISECOND, 0);

        if(calendarToday.getTimeInMillis() == calendarData.getTimeInMillis()) {
            result = true;
        }
    }catch (Exception exception){
        Log.e(TAG, exception);
    }
    return result;
}

Is ini_set('max_execution_time', 0) a bad idea?

Reason is to have some value other than zero. General practice to have it short globally and long for long working scripts like parsers, crawlers, dumpers, exporting & importing scripts etc.

  1. You can halt server, corrupt work of other people by memory consuming script without even knowing it.
  2. You will not be seeing mistakes where something, let's say, infinite loop happened, and it will be harder to diagnose.
  3. Such site may be easily DoSed by single user, when requesting pages with long execution time

MySQL, Concatenate two columns

$crud->set_relation('id','students','{first_name} {last_name}');
$crud->display_as('student_id','Students Name');

How to check if a string is a valid JSON string in JavaScript without using Try/Catch

I used a really simple method to check a string how it's a valid JSON or not.

function testJSON(text){
    if (typeof text!=="string"){
        return false;
    }
    try{
        JSON.parse(text);
        return true;
    }
    catch (error){
        return false;
    }
}

Result with a valid JSON string:

var input='["foo","bar",{"foo":"bar"}]';
testJSON(input); // returns true;

Result with a simple string;

var input='This is not a JSON string.';
testJSON(input); // returns false;

Result with an object:

var input={};
testJSON(input); // returns false;

Result with null input:

var input=null;
testJSON(input); // returns false;

The last one returns false because the type of null variables is object.

This works everytime. :)

How to log SQL statements in Spring Boot?

Please use:

logging.level.org.hibernate.SQL=DEBUG
logging.level.org.hibernate.type=TRACE
spring.jpa.show-sql=true

How to add many functions in ONE ng-click?

You have 2 options :

  1. Create a third method that wrap both methods. Advantage here is that you put less logic in your template.

  2. Otherwise if you want to add 2 calls in ng-click you can add ';' after edit($index) like this

    ng-click="edit($index); open()"

See here : http://jsfiddle.net/laguiz/ehTy6/

How to call javascript from a href?

If you only want to process a function and not process the href it self, add the return false statement at the end of your function:

 <a href="#" onclick="javascript: function() {... ; return false} return false">click</>

Call jQuery Ajax Request Each X Minutes

use jquery Every time Plugin .using this you can do ajax call for "X" time period

$("#select").everyTime(1000,function(i) {
//ajax call
}

you can also use setInterval

How to Clone Objects

Painlessly: Using NClone library

Person a = new Person() { head = "big", feet = "small" };
Person b = Clone.ObjectGraph(a); 

How can I send an HTTP POST request to a server from Excel using VBA?

If you need it to work on both Mac and Windows, you can use QueryTables:

With ActiveSheet.QueryTables.Add(Connection:="URL;http://carbon.brighterplanet.com/flights.txt", Destination:=Range("A2"))
    .PostText = "origin_airport=MSN&destination_airport=ORD"
    .RefreshStyle = xlOverwriteCells
    .SaveData = True
    .Refresh
End With

Notes:

  • Regarding output... I don't know if it's possible to return the results to the same cell that called the VBA function. In the example above, the result is written into A2.
  • Regarding input... If you want the results to refresh when you change certain cells, make sure those cells are the argument to your VBA function.
  • This won't work on Excel for Mac 2008, which doesn't have VBA. Excel for Mac 2011 got VBA back.

For more details, you can see my full summary about "using web services from Excel."

how to prevent "directory already exists error" in a makefile when using mkdir

A little simpler than Lars' answer:

something_needs_directory_xxx : xxx/..

and generic rule:

%/.. : ;@mkdir -p $(@D)

No touch-files to clean up or make .PRECIOUS :-)

If you want to see another little generic gmake trick, or if you're interested in non-recursive make with minimal scaffolding, you might care to check out Two more cheap gmake tricks and the other make-related posts in that blog.

How to apply a CSS filter to a background image

_x000D_
_x000D_
div {_x000D_
    background: inherit;_x000D_
    width: 250px;_x000D_
    height: 350px;_x000D_
    position: absolute;_x000D_
    overflow: hidden;  /* Adding overflow hidden */_x000D_
}_x000D_
_x000D_
div:before {_x000D_
    content: ‘’;_x000D_
    width: 300px;_x000D_
    height: 400px;_x000D_
    background: inherit;_x000D_
    position: absolute;_x000D_
    left: -25px;  /* Giving minus -25px left position */_x000D_
    right: 0;_x000D_
    top: -25px;   /* Giving minus -25px top position */_x000D_
    bottom: 0;_x000D_
    box-shadow: inset 0 0 0 200px rgba(255, 255, 255, 0.3);_x000D_
    filter: blur(10px);_x000D_
}
_x000D_
_x000D_
_x000D_

How to get the first day of the current week and month?

To get the first day of the month, simply get a Date and set the current day to day 1 of the month. Clear hour, minute, second and milliseconds if you need it.

private static Date firstDayOfMonth(Date date) {
   Calendar calendar = Calendar.getInstance();
   calendar.setTime(date);
   calendar.set(Calendar.DATE, 1);
   return calendar.getTime();
}

First day of the week is the same thing, but using Calendar.DAY_OF_WEEK instead

private static Date firstDayOfWeek(Date date) {
   Calendar calendar = Calendar.getInstance();
   calendar.setTime(date);
   calendar.set(Calendar.DAY_OF_WEEK, 1);
   return calendar.getTime();
}

no such file to load -- rubygems (LoadError)

I would just like to add that in my case rubygems wasn't installed.

Running sudo apt-get install rubygems solved the issue!

How can I find out what FOREIGN KEY constraint references a table in SQL Server?

Here it is:

SELECT 
   OBJECT_NAME(f.parent_object_id) TableName,
   COL_NAME(fc.parent_object_id,fc.parent_column_id) ColName
FROM 
   sys.foreign_keys AS f
INNER JOIN 
   sys.foreign_key_columns AS fc 
      ON f.OBJECT_ID = fc.constraint_object_id
INNER JOIN 
   sys.tables t 
      ON t.OBJECT_ID = fc.referenced_object_id
WHERE 
   OBJECT_NAME (f.referenced_object_id) = 'YourTableName'

This way, you'll get the referencing table and column name.

Edited to use sys.tables instead of generic sys.objects as per comment suggestion. Thanks, marc_s

How to crop an image using C#?

This is another way. In my case I have:

  • 2 numeric updown controls (called LeftMargin and TopMargin)
  • 1 Picture box (pictureBox1)
  • 1 button that I called generate
  • 1 image on C:\imagenes\myImage.gif

Inside the button I have this code:

Image myImage = Image.FromFile(@"C:\imagenes\myImage.gif");
Bitmap croppedBitmap = new Bitmap(myImage);
croppedBitmap = croppedBitmap.Clone(
            new Rectangle(
                (int)LeftMargin.Value, (int)TopMargin.Value,
                myImage.Width - (int)LeftMargin.Value,
                myImage.Height - (int)TopMargin.Value),
            System.Drawing.Imaging.PixelFormat.DontCare);
pictureBox1.Image = croppedBitmap;

I tried it in Visual studio 2012 using C#. I found this solution from this page

What is a Sticky Broadcast?

sendStickyBroadcast() performs a sendBroadcast(Intent) known as sticky, i.e. the Intent you are sending stays around after the broadcast is complete, so that others can quickly retrieve that data through the return value of registerReceiver(BroadcastReceiver, IntentFilter). In all other ways, this behaves the same as sendBroadcast(Intent). One example of a sticky broadcast sent via the operating system is ACTION_BATTERY_CHANGED. When you call registerReceiver() for that action -- even with a null BroadcastReceiver -- you get the Intent that was last broadcast for that action. Hence, you can use this to find the state of the battery without necessarily registering for all future state changes in the battery.

How to skip to next iteration in jQuery.each() util?

jQuery.noop() can help

$(".row").each( function() {
    if (skipIteration) {
        $.noop()
    }
    else{doSomething}
});

Display HTML form values in same page after submit using Ajax

Here is one way to do it.

<!DOCTYPE html>
<html>
  <head lang="en">
  <meta charset="UTF-8">
  <script language="JavaScript">
    function showInput() {
        document.getElementById('display').innerHTML = 
                    document.getElementById("user_input").value;
    }
  </script>

  </head>
<body>

  <form>
    <label><b>Enter a Message</b></label>
    <input type="text" name="message" id="user_input">
  </form>

  <input type="submit" onclick="showInput();"><br/>
  <label>Your input: </label>
  <p><span id='display'></span></p>
</body>
</html>

And this is what it looks like when run.Cheers.

enter image description here

Remove an element from a Bash array

Here's a one-line solution with mapfile:

$ mapfile -d $'\0' -t arr < <(printf '%s\0' "${arr[@]}" | grep -Pzv "<regexp>")

Example:

$ arr=("Adam" "Bob" "Claire"$'\n'"Smith" "David" "Eve" "Fred")

$ echo "Size: ${#arr[*]} Contents: ${arr[*]}"

Size: 6 Contents: Adam Bob Claire
Smith David Eve Fred

$ mapfile -d $'\0' -t arr < <(printf '%s\0' "${arr[@]}" | grep -Pzv "^Claire\nSmith$")

$ echo "Size: ${#arr[*]} Contents: ${arr[*]}"

Size: 5 Contents: Adam Bob David Eve Fred

This method allows for great flexibility by modifying/exchanging the grep command and doesn't leave any empty strings in the array.

Ruby convert Object to Hash

You should override the inspect method of your object to return the desired hash, or just implement a similar method without overriding the default object behaviour.

If you want to get fancier, you can iterate over an object's instance variables with object.instance_variables

try/catch blocks with async/await

Alternative Similar To Error Handling In Golang

Because async/await uses promises under the hood, you can write a little utility function like this:

export function catchEm(promise) {
  return promise.then(data => [null, data])
    .catch(err => [err]);
}

Then import it whenever you need to catch some errors, and wrap your async function which returns a promise with it.

import catchEm from 'utility';

async performAsyncWork() {
  const [err, data] = await catchEm(asyncFunction(arg1, arg2));
  if (err) {
    // handle errors
  } else {
    // use data
  }
}

How to iterate over each string in a list of strings and operate on it's elements

You are iterating trough items in words but you have to iterate through item's length:

words = ['aba', 'xyz', 'xgx', 'dssd', 'sdjh']
c = 0
for i in range(len(words)):
    w1 = words[i]
    if w1[0] == w1[len(w1) - 1]:
      c += 1
    print (c)

In your case i[0] is 'aba' because i is calculated from items in words:

words = ['aba', 'xyz', 'xgx', 'dssd', 'sdjh']
c = 0
for i in words:
print(i)

the output is:

aba

How to Get True Size of MySQL Database?

None of the answers include the overhead size and the metadata sizes of tables.

Here is a more accurate estimation of the "disk space" allocated by a database.

SELECT ROUND((SUM(data_length+index_length+data_free) + (COUNT(*) * 300 * 1024))/1048576+150, 2) AS MegaBytes FROM information_schema.TABLES WHERE table_schema = 'DATABASE-NAME'

Using CSS :before and :after pseudo-elements with inline CSS?

as mentioned above: its not possible to call a css pseudo-class / -element inline. what i now did, is: give your element a unique identifier, f.ex. an id or a unique class. and write a fitting <style> element

<style>#id29:before { content: "*";}</style>
<article id="id29">
  <!-- something -->
</article>

fugly, but what inline css isnt..?

Invert "if" statement to reduce nesting

This is a bit of a religious argument, but I agree with ReSharper that you should prefer less nesting. I believe that this outweighs the negatives of having multiple return paths from a function.

The key reason for having less nesting is to improve code readability and maintainability. Remember that many other developers will need to read your code in the future, and code with less indentation is generally much easier to read.

Preconditions are a great example of where it is okay to return early at the start of the function. Why should the readability of the rest of the function be affected by the presence of a precondition check?

As for the negatives about returning multiple times from a method - debuggers are pretty powerful now, and it's very easy to find out exactly where and when a particular function is returning.

Having multiple returns in a function is not going to affect the maintainance programmer's job.

Poor code readability will.

How to draw a custom UIView that is just a circle - iPhone app

Here is another way by using UIBezierPath (maybe it's too late ^^) Create a circle and mask UIView with it, as follows:

UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 200, 200)];
view.backgroundColor = [UIColor blueColor];

CAShapeLayer *shape = [CAShapeLayer layer];
UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:view.center radius:(view.bounds.size.width / 2) startAngle:0 endAngle:(2 * M_PI) clockwise:YES];
shape.path = path.CGPath;
view.layer.mask = shape;

Dynamically change bootstrap progress bar value when checkboxes checked

Bootstrap 4 progress bar

<div class="progress">
<div class="progress-bar" role="progressbar" style="" aria-valuenow="" aria-valuemin="0" aria-valuemax="100"></div>
</div>

Javascript

change progress bar on next/previous page actions

var count = Number(document.getElementById('count').innerHTML); //set this on page load in a hidden field after an ajax call
var total = document.getElementById('total').innerHTML; //set this on initial page load
var pcg = Math.floor(count/total*100);        
document.getElementsByClassName('progress-bar').item(0).setAttribute('aria-valuenow',pcg);
document.getElementsByClassName('progress-bar').item(0).setAttribute('style','width:'+Number(pcg)+'%');

Max size of URL parameters in _GET

See What is the maximum length of a URL in different browsers?

The length of the url can't be changed in PHP. The linked question is about the URL size limit, you will find what you want.

Javascript to convert UTC to local time

var offset = new Date().getTimezoneOffset();

offset will be the interval in minutes from Local time to UTC. To get Local time from a UTC date, you would then subtract the minutes from your date.

utc_date.setMinutes(utc_date.getMinutes() - offset);

Using Git, show all commits that are in one branch, but not the other(s)

If it is one (single) branch that you need to check, for example if you want that branch 'B' is fully merged into branch 'A', you can simply do the following:

$ git checkout A
$ git branch -d B

git branch -d <branchname> has the safety that "The branch must be fully merged in HEAD."

Caution: this actually deletes the branch B if it is merged into A.

Git fetch remote branch

A simple command, git checkout remote_branch_name will help you to create a local branch that has all the changes in the remote branch.

How do I check for vowels in JavaScript?

I created a simplified version using Array.prototype.includes(). My technique is similar to @Kunle Babatunde.

_x000D_
_x000D_
const isVowel = (char) => ["a", "e", "i", "o", "u"].includes(char);_x000D_
_x000D_
console.log(isVowel("o"), isVowel("s"));
_x000D_
_x000D_
_x000D_

Styling of Select2 dropdown select boxes

Here is a working example of above. http://jsfiddle.net/z7L6m2sc/ Now select2 has been updated the classes have change may be why you cannot get it to work. Here is the css....

.select2-dropdown.select2-dropdown--below{
    width: 148px !important;
}

.select2-container--default .select2-selection--single{
    padding:6px;
    height: 37px;
    width: 148px; 
    font-size: 1.2em;  
    position: relative;
}

.select2-container--default .select2-selection--single .select2-selection__arrow {
    background-image: -khtml-gradient(linear, left top, left bottom, from(#424242), to(#030303));
    background-image: -moz-linear-gradient(top, #424242, #030303);
    background-image: -ms-linear-gradient(top, #424242, #030303);
    background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #424242), color-stop(100%, #030303));
    background-image: -webkit-linear-gradient(top, #424242, #030303);
    background-image: -o-linear-gradient(top, #424242, #030303);
    background-image: linear-gradient(#424242, #030303);
    width: 40px;
    color: #fff;
    font-size: 1.3em;
    padding: 4px 12px;
    height: 27px;
    position: absolute;
    top: 0px;
    right: 0px;
    width: 20px;
}

Get error message if ModelState.IsValid fails?

It is sample extension

public class GetModelErrors
{
    //Usage return Json to View :
    //return Json(new { state = false, message = new GetModelErrors(ModelState).MessagesWithKeys() });
    public class KeyMessages
    {
        public string Key { get; set; }
        public string Message { get; set; }
    }
    private readonly ModelStateDictionary _entry;
    public GetModelErrors(ModelStateDictionary entry)
    {
        _entry = entry;
    }

    public int Count()
    {
        return _entry.ErrorCount;
    }
    public string Exceptions(string sp = "\n")
    {
        return string.Join(sp, _entry.Values
            .SelectMany(v => v.Errors)
            .Select(e => e.Exception));
    }
    public string Messages(string sp = "\n")
    {
        string msg = string.Empty;
        foreach (var item in _entry)
        {
            if (item.Value.ValidationState == ModelValidationState.Invalid)
            {
                msg += string.Join(sp, string.Join(",", item.Value.Errors.Select(i => i.ErrorMessage)));
            }
        }
        return msg;
    }

    public List<KeyMessages> MessagesWithKeys(string sp = "<p> ? ")
    {
        List<KeyMessages> list = new List<KeyMessages>();
        foreach (var item in _entry)
        {
            if (item.Value.ValidationState == ModelValidationState.Invalid)
            {
                list.Add(new KeyMessages
                {
                    Key = item.Key,
                    Message = string.Join(null, item.Value.Errors.Select(i => sp + i.ErrorMessage))
                });
            }
        }
        return list;
    }
}

SOAP-UI - How to pass xml inside parameter

NOTE: This one is just an alternative for the previous provided .NET framework 3.5 and above

You can send it as raw xml

<test>or like this</test>

If you declare the paramater2 as XElement data type

How to edit hosts file via CMD?

Use Hosts Commander. It's simple and powerful. Translated description (from russian) here.

Examples of using

hosts add another.dev 192.168.1.1 # Remote host
hosts add test.local # 127.0.0.1 used by default
hosts set myhost.dev # new comment
hosts rem *.local
hosts enable local*
hosts disable localhost

...and many others...

Help

Usage:
    hosts - run hosts command interpreter
    hosts <command> <params> - execute hosts command

Commands:
    add  <host> <aliases> <addr> # <comment>   - add new host
    set  <host|mask> <addr> # <comment>        - set ip and comment for host
    rem  <host|mask>   - remove host
    on   <host|mask>   - enable host
    off  <host|mask>   - disable host
    view [all] <mask>  - display enabled and visible, or all hosts
    hide <host|mask>   - hide host from 'hosts view'
    show <host|mask>   - show host in 'hosts view'
    print      - display raw hosts file
    format     - format host rows
    clean      - format and remove all comments
    rollback   - rollback last operation
    backup     - backup hosts file
    restore    - restore hosts file from backup
    recreate   - empty hosts file
    open       - open hosts file in notepad

Download

https://code.google.com/p/hostscmd/downloads/list

how to make negative numbers into positive

abs() is for integers only. For floating point, use fabs() (or one of the fabs() line with the correct precision for whatever a actually is)

compareTo with primitives -> Integer / int

May I propose a third

((Integer) a).compareTo(b)  

How do I get the current mouse screen coordinates in WPF?

Do you want coordinates relative to the screen or the application?

If it's within the application just use:

Mouse.GetPosition(Application.Current.MainWindow);

If not, I believe you can add a reference to System.Windows.Forms and use:

System.Windows.Forms.Control.MousePosition;

AttributeError: can't set attribute in python

items[node.ind] = items[node.ind]._replace(v=node.v)

(Note: Don't be discouraged to use this solution because of the leading underscore in the function _replace. Specifically for namedtuple some functions have leading underscore which is not for indicating they are meant to be "private")

Better way of getting time in milliseconds in javascript?

As far that I know you only can get time with Date.

Date.now is the solution but is not available everywhere : https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Date/now.

var currentTime = +new Date();

This gives you the current time in milliseconds.

For your jumps. If you compute interpolations correctly according to the delta frame time and you don't have some rounding number error, I bet for the garbage collector (GC).

If there is a lot of created temporary object in your loop, garbage collection has to lock the thread to make some cleanup and memory re-organization.

With Chrome you can see how much time the GC is spending in the Timeline panel.

EDIT: Since my answer, Date.now() should be considered as the best option as it is supported everywhere and on IE >= 9.

Oracle - Why does the leading zero of a number disappear when converting it TO_CHAR

Below format try if number is like

ex 1 suppose number like 10.1 if apply below format it will be come as 10.10

ex 2 suppose number like .02 if apply below format it will be come as 0.02

ex 3 suppose number like 0.2 if apply below format it will be come as 0.20

to_char(round(to_number(column_name)/10000000,2),'999999999990D99') as column_name

How do I reverse a C++ vector?

#include<algorithm>
#include<vector>
#include<iostream>
using namespace std;
int main()
{
    vector<int>v1;
    for(int i=0; i<5; i++)
        v1.push_back(i*2);
    for(int i=0; i<v1.size(); i++)
        cout<<v1[i];    //02468
    reverse(v1.begin(),v1.end());
    
    for(int i=0; i<v1.size(); i++)
        cout<<v1[i];   //86420
}

Android: Getting a file URI from a content URI?

Well I am bit late to answer,but my code is tested

check scheme from uri:

 byte[] videoBytes;

if (uri.getScheme().equals("content")){
        InputStream iStream =   context.getContentResolver().openInputStream(uri);
            videoBytes = getBytes(iStream);
        }else{
            File file = new File(uri.getPath());
            FileInputStream fileInputStream = new FileInputStream(file);     
            videoBytes = getBytes(fileInputStream);
        }

In the above answer I converted the video uri to bytes array , but that's not related to question, I just copied my full code to show the usage of FileInputStream and InputStream as both are working same in my code.

I used the variable context which is getActivity() in my Fragment and in Activity it simply be ActivityName.this

context=getActivity(); //in Fragment

context=ActivityName.this;// in activity

MySQL: Error Code: 1118 Row size too large (> 8126). Changing some columns to TEXT or BLOB

I struggled with the same error code recently, due to a change in MySQL Server 5.6.20. I was able to solve the problem by changing the innodb_log_file_size in the my.ini text file.

In the release notes, it is explained that an innodb_log_file_size that is too small will trigger a "Row size too large error."

http://dev.mysql.com/doc/relnotes/mysql/5.6/en/news-5-6-20.html

Socket send and receive byte array

You need to either have the message be a fixed size, or you need to send the size or you need to use some separator characters.

This is the easiest case for a known size (100 bytes):

in = new DataInputStream(server.getInputStream());
byte[] message = new byte[100]; // the well known size
in.readFully(message);

In this case DataInputStream makes sense as it offers readFully(). If you don't use it, you need to loop yourself until the expected number of bytes is read.

Create excel ranges using column numbers in vba?

To reference range of cells you can use Range(Cell1,Cell2), sample:

Sub RangeTest()
  Dim testRange As Range
  Dim targetWorksheet As Worksheet
  
  Set targetWorksheet = Worksheets("MySheetName")
  
  With targetWorksheet
    .Cells(5, 10).Select 'selects cell J5 on targetWorksheet
    Set testRange = .Range(.Cells(5, 5), .Cells(10, 10))
  End With
  
  testRange.Select 'selects range of cells E5:J10 on targetWorksheet
  
End Sub

enter image description here

Create empty data frame with column names by assigning a string vector?

How about:

df <- data.frame(matrix(ncol = 3, nrow = 0))
x <- c("name", "age", "gender")
colnames(df) <- x

To do all these operations in one-liner:

setNames(data.frame(matrix(ncol = 3, nrow = 0)), c("name", "age", "gender"))

#[1] name   age    gender
#<0 rows> (or 0-length row.names)

Or

data.frame(matrix(ncol=3,nrow=0, dimnames=list(NULL, c("name", "age", "gender"))))

Max parallel http connections in a browser?

The 2 concurrent requests is an intentional part of the design of many browsers. There is a standard out there that "good http clients" adhere to on purpose. Check out this RFC to see why.

Can I use library that used android support with Androidx projects.

Add the lines in the gradle.properties file

android.useAndroidX=true
android.enableJetifier=true

enter image description here enter image description here Refer also https://developer.android.com/jetpack/androidx

What operator is <> in VBA

This is an Inequality operator.

Also,this might be helpful for future: Operators listed by Functionality

vertical divider between two columns in bootstrap

If you want a vertical divider between 2 columns, all you need is add

class="col-6 border-left" 

to one of your column div-s

BUT

In the world of responsive design, you may need to make it disappear sometimes.

The solution is disappearing <hr> + disappearing <div> + margin-left: -1px;

<div class="container">
  <div class="row">
    <div class="col-md-7">
      1 of 2
    </div>
    <div class="border-left d-sm-none d-md-block" style="width: 0px;"></div>
    <div class="col-md-5" style="margin-left: -1px;">
    <hr class="d-sm-block d-md-none">
      2 of 2
    </div>
  </div>
</div>

https://jsfiddle.net/8z1pag7s/

tested on Bootstrap 4.1

Convert a List<T> into an ObservableCollection<T>

ObervableCollection have constructor in which you can pass your list. Quoting MSDN:

 public ObservableCollection(
      List<T> list
 )

Linq: GroupBy, Sum and Count

The following query works. It uses each group to do the select instead of SelectMany. SelectMany works on each element from each collection. For example, in your query you have a result of 2 collections. SelectMany gets all the results, a total of 3, instead of each collection. The following code works on each IGrouping in the select portion to get your aggregate operations working correctly.

var results = from line in Lines
              group line by line.ProductCode into g
              select new ResultLine {
                ProductName = g.First().Name,
                Price = g.Sum(pc => pc.Price).ToString(),
                Quantity = g.Count().ToString(),
              };

What's the difference between a single precision and double precision floating point operation?

Okay, the basic difference at the machine is that double precision uses twice as many bits as single. In the usual implementation,that's 32 bits for single, 64 bits for double.

But what does that mean? If we assume the IEEE standard, then a single precision number has about 23 bits of the mantissa, and a maximum exponent of about 38; a double precision has 52 bits for the mantissa, and a maximum exponent of about 308.

The details are at Wikipedia, as usual.

Determine direct shared object dependencies of a Linux binary?

ldd -v prints the dependency tree under "Version information:' section. The first block in that section are the direct dependencies of the binary.

See Hierarchical ldd(1)

macro for Hide rows in excel 2010

Well, you're on the right path, Benno!

There are some tips regarding VBA programming that might help you out.

  1. Use always explicit references to the sheet you want to interact with. Otherwise, Excel may 'assume' your code applies to the active sheet and eventually you'll see it screws your spreadsheet up.

  2. As lionz mentioned, get in touch with the native methods Excel offers. You might use them on most of your tricks.

  3. Explicitly declare your variables... they'll show the list of methods each object offers in VBA. It might save your time digging on the internet.

Now, let's have a draft code...

Remember this code must be within the Excel Sheet object, as explained by lionz. It only applies to Sheet 2, is up to you to adapt it to both Sheet 2 and Sheet 3 in the way you prefer.

Hope it helps!

Private Sub Worksheet_Change(ByVal Target As Range)

    Dim oSheet As Excel.Worksheet

    'We only want to do something if the changed cell is B6, right?
    If Target.Address = "$B$6" Then

        'Checks if it's a number...
        If IsNumeric(Target.Value) Then

            'Let's avoid values out of your bonds, correct?
            If Target.Value > 0 And Target.Value < 51 Then

                'Let's assign the worksheet we'll show / hide rows to one variable and then
                '   use only the reference to the variable itself instead of the sheet name.
                '   It's safer.

                'You can alternatively replace 'sheet 2' by 2 (without quotes) which will represent
                '   the sheet index within the workbook
                Set oSheet = ActiveWorkbook.Sheets("Sheet 2")

                'We'll unhide before hide, to ensure we hide the correct ones
                oSheet.Range("A7:A56").EntireRow.Hidden = False

                oSheet.Range("A" & Target.Value + 7 & ":A56").EntireRow.Hidden = True

            End If

        End If

    End If

End Sub

How to convert string to boolean in typescript Angular 4

Method 1 :

var stringValue = "true";
var boolValue = (/true/i).test(stringValue) //returns true

Method 2 :

var stringValue = "true";
var boolValue = (stringValue =="true");   //returns true

Method 3 :

var stringValue = "true";
var boolValue = JSON.parse(stringValue);   //returns true

Method 4 :

var stringValue = "true";
var boolValue = stringValue.toLowerCase() == 'true'; //returns true

Method 5 :

var stringValue = "true";
var boolValue = getBoolean(stringValue); //returns true
function getBoolean(value){
   switch(value){
        case true:
        case "true":
        case 1:
        case "1":
        case "on":
        case "yes":
            return true;
        default: 
            return false;
    }
}

source: http://codippa.com/how-to-convert-string-to-boolean-javascript/

Class has no initializers Swift

simply provide the init block for HomeCell class

it's work in my case

Java - How to create a custom dialog box?

i created a custom dialog API. check it out here https://github.com/MarkMyWord03/CustomDialog. It supports message and confirmation box. input and option dialog just like in joptionpane will be implemented soon.

Sample Error Dialog from CUstomDialog API: CustomDialog Error Message

How to convert List<Integer> to int[] in Java?

In addition to Commons Lang, you can do this with Guava's method Ints.toArray(Collection<Integer> collection):

List<Integer> list = ...
int[] ints = Ints.toArray(list);

This saves you having to do the intermediate array conversion that the Commons Lang equivalent requires yourself.

How to set HttpResponse timeout for Android in Java

For those saying that the answer of @kuester2000 does not work, please be aware that HTTP requests, first try to find the host IP with a DNS request and then makes the actual HTTP request to the server, so you may also need to set a timeout for the DNS request.

If your code worked without the timeout for the DNS request it's because you are able to reach a DNS server or you are hitting the Android DNS cache. By the way you can clear this cache by restarting the device.

This code extends the original answer to include a manual DNS lookup with a custom timeout:

//Our objective
String sURL = "http://www.google.com/";
int DNSTimeout = 1000;
int HTTPTimeout = 2000;

//Get the IP of the Host
URL url= null;
try {
     url = ResolveHostIP(sURL,DNSTimeout);
} catch (MalformedURLException e) {
    Log.d("INFO",e.getMessage());
}

if(url==null){
    //the DNS lookup timed out or failed.
}

//Build the request parameters
HttpParams params = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(params, HTTPTimeout);
HttpConnectionParams.setSoTimeout(params, HTTPTimeout);

DefaultHttpClient client = new DefaultHttpClient(params);

HttpResponse httpResponse;
String text;
try {
    //Execute the request (here it blocks the execution until finished or a timeout)
    httpResponse = client.execute(new HttpGet(url.toString()));
} catch (IOException e) {
    //If you hit this probably the connection timed out
    Log.d("INFO",e.getMessage());
}

//If you get here everything went OK so check response code, body or whatever

Used method:

//Run the DNS lookup manually to be able to time it out.
public static URL ResolveHostIP (String sURL, int timeout) throws MalformedURLException {
    URL url= new URL(sURL);
    //Resolve the host IP on a new thread
    DNSResolver dnsRes = new DNSResolver(url.getHost());
    Thread t = new Thread(dnsRes);
    t.start();
    //Join the thread for some time
    try {
        t.join(timeout);
    } catch (InterruptedException e) {
        Log.d("DEBUG", "DNS lookup interrupted");
        return null;
    }

    //get the IP of the host
    InetAddress inetAddr = dnsRes.get();
    if(inetAddr==null) {
        Log.d("DEBUG", "DNS timed out.");
        return null;
    }

    //rebuild the URL with the IP and return it
    Log.d("DEBUG", "DNS solved.");
    return new URL(url.getProtocol(),inetAddr.getHostAddress(),url.getPort(),url.getFile());
}   

This class is from this blog post. Go and check the remarks if you will use it.

public static class DNSResolver implements Runnable {
    private String domain;
    private InetAddress inetAddr;

    public DNSResolver(String domain) {
        this.domain = domain;
    }

    public void run() {
        try {
            InetAddress addr = InetAddress.getByName(domain);
            set(addr);
        } catch (UnknownHostException e) {
        }
    }

    public synchronized void set(InetAddress inetAddr) {
        this.inetAddr = inetAddr;
    }
    public synchronized InetAddress get() {
        return inetAddr;
    }
}

Catch Ctrl-C in C

#include<stdio.h>
#include<signal.h>
#include<unistd.h>

void sig_handler(int signo)
{
  if (signo == SIGINT)
    printf("received SIGINT\n");
}

int main(void)
{
  if (signal(SIGINT, sig_handler) == SIG_ERR)
  printf("\ncan't catch SIGINT\n");
  // A long long wait so that we can easily issue a signal to this process
  while(1) 
    sleep(1);
  return 0;
}

The function sig_handler checks if the value of the argument passed is equal to the SIGINT, then the printf is executed.

AngularJS : Prevent error $digest already in progress when calling $scope.$apply()

yearofmoo did a great job at creating a reusable $safeApply function for us :

https://github.com/yearofmoo/AngularJS-Scope.SafeApply

Usage :

//use by itself
$scope.$safeApply();

//tell it which scope to update
$scope.$safeApply($scope);
$scope.$safeApply($anotherScope);

//pass in an update function that gets called when the digest is going on...
$scope.$safeApply(function() {

});

//pass in both a scope and a function
$scope.$safeApply($anotherScope,function() {

});

//call it on the rootScope
$rootScope.$safeApply();
$rootScope.$safeApply($rootScope);
$rootScope.$safeApply($scope);
$rootScope.$safeApply($scope, fn);
$rootScope.$safeApply(fn);

Iterate through every file in one directory

Dir has also shorter syntax to get an array of all files from directory:

Dir['dir/to/files/*'].each do |fname|
    # do something with fname
end

Google Script to see if text contains a value

I had to add a .toString to the item in the values array. Without it, it would only match if the entire cell body matched the searchTerm.

function foo() {
    var ss = SpreadsheetApp.getActiveSpreadsheet();
    var s = ss.getSheetByName('spreadsheet-name');
    var r = s.getRange('A:A');
    var v = r.getValues();
    var searchTerm = 'needle';
    for(var i=v.length-1;i>=0;i--) {
        if(v[0,i].toString().indexOf(searchTerm) > -1) {
            // do something
        }
    }
};

mysqli_real_connect(): (HY000/2002): No such file or directory

Try just

sudo service mysql restart

It worked for me

Get the current date in java.sql.Date format

new java.sql.Date(Calendar.getInstance().getTimeInMillis());

Can someone explain mappedBy in JPA and Hibernate?

By specifying the @JoinColumn on both models you don't have a two way relationship. You have two one way relationships, and a very confusing mapping of it at that. You're telling both models that they "own" the IDAIRLINE column. Really only one of them actually should! The 'normal' thing is to take the @JoinColumn off of the @OneToMany side entirely, and instead add mappedBy to the @OneToMany.

@OneToMany(cascade = CascadeType.ALL, mappedBy="airline")
public Set<AirlineFlight> getAirlineFlights() {
    return airlineFlights;
}

That tells Hibernate "Go look over on the bean property named 'airline' on the thing I have a collection of to find the configuration."

Using Bootstrap Modal window as PartialView

Yes we have done this.

In your Index.cshtml you'll have something like..

<div id='gameModal' class='modal hide fade in' data-url='@Url.Action("GetGameListing")'>
   <div id='gameContainer'>
   </div>
</div>

<button id='showGame'>Show Game Listing</button>

Then in JS for the same page (inlined or in a separate file you'll have something like this..

$(document).ready(function() {
   $('#showGame').click(function() {
        var url = $('#gameModal').data('url');

        $.get(url, function(data) {
            $('#gameContainer').html(data);

            $('#gameModal').modal('show');
        });
   });
});

With a method on your controller that looks like this..

[HttpGet]
public ActionResult GetGameListing()
{
   var model = // do whatever you need to get your model
   return PartialView(model);
}

You will of course need a view called GetGameListing.cshtml inside of your Views folder..

Pass Multiple Parameters to jQuery ajax call

I successfully passed multiple parameters using json

data: "{'RecomendeeName':'" + document.getElementById('txtSearch').value + "'," + "'tempdata':'" +"myvalue" + "'}",

How to select only the first rows for each unique value of a column?

You can use the row_numer() over(partition by ...) syntax like so:

select * from
(
select *
, ROW_NUMBER() OVER(PARTITION BY CName ORDER BY AddressLine) AS row
from myTable
) as a
where row = 1

What this does is that it creates a column called row, which is a counter that increments every time it sees the same CName, and indexes those occurrences by AddressLine. By imposing where row = 1, one can select the CName whose AddressLine comes first alphabetically. If the order by was desc, then it would pick the CName whose AddressLine comes last alphabetically.

How to vertically align <li> elements in <ul>?

You can use flexbox for this.

ul {
    display: flex;
    align-items: center;
}

A detailed explanation of how to use flexbox can be found here.

Excel VBA - Range.Copy transpose paste

Here's an efficient option that doesn't use the clipboard.

Sub transposeAndPasteRow(rowToCopy As Range, pasteTarget As Range)
    pasteTarget.Resize(rowToCopy.Columns.Count) = Application.WorksheetFunction.Transpose(rowToCopy.Value)
End Sub

Use it like this.

Sub test()
    Call transposeAndPasteRow(Worksheets("Sheet1").Range("A1:A5"), Worksheets("Sheet2").Range("A1"))
End Sub

How to change symbol for decimal point in double.ToString()?

If you have an Asp.Net web application, you can also set it in the web.config so that it is the same throughout the whole web application

<system.web>
    ...
    <globalization 
        requestEncoding="utf-8" 
        responseEncoding="utf-8" 
        culture="en-GB" 
        uiCulture="en-GB" 
        enableClientBasedCulture="false"/>
    ...
</system.web>

Show how many characters remaining in a HTML text box using JavaScript

I needed something like that and the solution I gave with the help of jquery is this:

<textarea class="textlimited" data-textcounterid="counter1" maxlength="30">text</textarea>
<span class='textcounter' id="counter1"></span>

With this script:

// the selector below will catch the keyup events of elements decorated with class textlimited and have a maxlength
$('.textlimited[maxlength]').keyup(function(){
     //get the fields limit
    var maxLength = $(this).attr("maxlength");

    // check if the limit is passed
    if(this.value.length > maxLength){
        return false;
    }

    // find the counter element by the id specified in the source input element
    var counterElement = $(".textcounter#" + $(this).data("textcounterid"));
    // update counter 's text
    counterElement.html((maxLength - this.value.length) + " chars left");
});

? live demo Here

How to search by key=>value in a multidimensional array in PHP

http://snipplr.com/view/51108/nested-array-search-by-value-or-key/

<?php

//PHP 5.3

function searchNestedArray(array $array, $search, $mode = 'value') {

    foreach (new RecursiveIteratorIterator(new RecursiveArrayIterator($array)) as $key => $value) {
        if ($search === ${${"mode"}})
            return true;
    }
    return false;
}

$data = array(
    array('abc', 'ddd'),
    'ccc',
    'bbb',
    array('aaa', array('yyy', 'mp' => 555))
);

var_dump(searchNestedArray($data, 555));

check if file exists in php

  1. The function expects a string.

  2. file_exists() does not work properly with HTTP URLs.

org.springframework.beans.factory.BeanCreationException: Error creating bean with name

you need to add jar file in your build path..

commons-dbcp-1.1-RC2.jar

or any version of that..!!!!

ADDED : also make sure you have commons-pool-1.1.jar too in your build path.

ADDED: sorry saw complete list of jar late... may be version clashes might be there.. better check out..!!! just an assumption.

Can not find module “@angular-devkit/build-angular”

Running ng serve --open after creating and going into my new project "frontend" gave this error:

After creating the project, you need to run

npm install 

to install all the dependencies listed in package.json

Sending string via socket (python)

This piece of code is incorrect.

while 1:
    (clientsocket, address) = serversocket.accept()
    print ("connection found!")
    data = clientsocket.recv(1024).decode()
    print (data)
    r='REceieve'
    clientsocket.send(r.encode())

The call on accept() on the serversocket blocks until there's a client connection. When you first connect to the server from the client, it accepts the connection and receives data. However, when it enters the loop again, it is waiting for another connection and thus blocks as there are no other clients that are trying to connect.

That's the reason the recv works correct only the first time. What you should do is find out how you can handle the communication with a client that has been accepted - maybe by creating a new Thread to handle communication with that client and continue accepting new clients in the loop, handling them in the same way.

Tip: If you want to work on creating your own chat application, you should look at a networking engine like Twisted. It will help you understand the whole concept better too.

Jquery to change form action

Try this:

$('#button1').click(function(){
   $('#formId').attr('action', 'page1');
});


$('#button2').click(function(){
   $('#formId').attr('action', 'page2');
});

C# string does not contain possible?

You should put all your words into some kind of Collection or List and then call it like this:

var searchFor = new List<string>();
searchFor.Add("pineapple");
searchFor.Add("mango");

bool containsAnySearchString = searchFor.Any(word => compareString.Contains(word));

If you need to make a case or culture independent search you should call it like this:

bool containsAnySearchString = 
   searchFor.Any(word => compareString.IndexOf
     (word, StringComparison.InvariantCultureIgnoreCase >= 0);

What's the best way to add a drop shadow to my UIView

The trick is defining the masksToBounds property of your view's layer properly:

view.layer.masksToBounds = NO;

and it should work.

(Source)

How do I get the name of the current executable in C#?

If you need the Program name to set up a firewall rule, use:

System.Diagnostics.Process.GetCurrentProcess().MainModule.FileName

This will ensure that the name is correct both when debugging in VisualStudio and when running the app directly in windows.

Is there a better way to do optional function parameters in JavaScript?

With ES2015/ES6 you can take advantage of Object.assign which can replace $.extend() or _.defaults()

function myFunc(requiredArg, options = {}) {
  const defaults = {
    message: 'Hello',
    color: 'red',
    importance: 1
  };

  const settings = Object.assign({}, defaults, options);

  // do stuff
}

You can also use defaults arguments like this

function myFunc(requiredArg, { message: 'Hello', color: 'red', importance: 1 } = {}) {
  // do stuff
}

simple vba code gives me run time error 91 object variable or with block not set

Check the version of the excel, if you are using older version then Value2 is not available for you and thus it is showing an error, while it will work with 2007+ version. Or the other way, the object is not getting created and thus the Value2 property is not available for the object.

Running CMake on Windows

The default generator for Windows seems to be set to NMAKE. Try to use:

cmake -G "MinGW Makefiles"

Or use the GUI, and select MinGW Makefiles when prompted for a generator. Don't forget to cleanup the directory where you tried to run CMake, or delete the cache in the GUI. Otherwise, it will try again with NMAKE.

Read int values from a text file in C

A simple solution using fscanf:

void read_ints (const char* file_name)
{
  FILE* file = fopen (file_name, "r");
  int i = 0;

  fscanf (file, "%d", &i);    
  while (!feof (file))
    {  
      printf ("%d ", i);
      fscanf (file, "%d", &i);      
    }
  fclose (file);        
}

How to show two figures using matplotlib?

Alternatively to calling plt.show() at the end of the script, you can also control each figure separately doing:

f = plt.figure(1)
plt.hist........
............
f.show()

g = plt.figure(2)
plt.hist(........
................
g.show()

raw_input()

In this case you must call raw_input to keep the figures alive. This way you can select dynamically which figures you want to show

Note: raw_input() was renamed to input() in Python 3

Transfer data from one HTML file to another

The old fashioned way of setting a global variable that persist between pages is to set the data in a Cookie. The modern way is to use Local Storage, which has a good browser support (IE8+, Firefox 3.5+, Chrome 4+, Android 2+, iPhone 2+). Using localStorage is as easy as using an array:

localStorage["key"] = value;

... in another page ...
value = localStorage["key"];

You can also attach event handlers to listen for changes, though the event API is slightly different between browsers. More on the topic.

How to recover stashed uncommitted changes

you can stash the uncommitted changes using "git stash" then checkout to a new branch using "git checkout -b " then apply the stashed commits "git stash apply"

DateTime.Now.ToString("yyyy-MM-dd hh:mm:ss") is returning AM time instead of PM time?

With C#6.0 you also have a new way of formatting date when using string interpolation e.g.

$"{DateTime.Now:yyyy-MM-dd HH:mm:ss}"

Can't say its any better, but it is slightly cleaner if including the formatted DateTime in a longer string.

More about string interpolation.

How to make readonly all inputs in some div in Angular2?

If you want to do a whole group, not just one field at a time, you can use the HTML5 <fieldset> tag.

<fieldset [disabled]="killfields ? 'disabled' : null">

    <!-- fields go here -->

</fieldset>

How link to any local file with markdown syntax?

After messing around with @BringBackCommodore64 answer I figured it out

[link](file:///d:/absolute.md)    # absolute filesystem path
[link](./relative1.md)            # relative to opened file
[link](/relativeToProject.md)     # relative to opened project

All of them tested in Visual Studio Code and working,

Note: The absolute path works in editor but doesn't work in markdown preview mode!

Iterator over HashMap in Java

Several problems here:

  • You probably don't use the correct iterator class. As others said, use import java.util.Iterator
  • If you want to use Map.Entry entry = (Map.Entry) iter.next(); then you need to use hm.entrySet().iterator(), not hm.keySet().iterator(). Either you iterate on the keys, or on the entries.

If/else else if in Jquery for a condition

See this answer. val() is comparing a string, not a numeric value.

Rails how to run rake task

Rake::Task['reklamer:orville'].invoke

or

Rake::Task['reklamer:orville'].invoke(args)

How to cat <<EOF >> a file containing code?

I know this is a two year old question, but this is a quick answer for those searching for a 'how to'.

If you don't want to have to put quotes around anything you can simply write a block of text to a file, and escape variables you want to export as text (for instance for use in a script) and not escape one's you want to export as the value of the variable.

#!/bin/bash

FILE_NAME="test.txt"
VAR_EXAMPLE="\"string\""

cat > ${FILE_NAME} << EOF
\${VAR_EXAMPLE}=${VAR_EXAMPLE} in ${FILE_NAME}  
EOF

Will write "${VAR_EXAMPLE}="string" in test.txt" into test.txt

This can also be used to output blocks of text to the console with the same rules by omitting the file name

#!/bin/bash

VAR_EXAMPLE="\"string\""

cat << EOF
\${VAR_EXAMPLE}=${VAR_EXAMPLE} to console 
EOF

Will output "${VAR_EXAMPLE}="string" to console" to the console

How can I pass arguments to anonymous functions in JavaScript?

The delegates:

function displayMessage(message, f)
{
    f(message); // execute function "f" with variable "message"
}

function alerter(message)
{
    alert(message);
}

function writer(message)
{
    document.write(message);
}

Running the displayMessage function:

function runDelegate()
{
    displayMessage("Hello World!", alerter); // alert message

    displayMessage("Hello World!", writer); // write message to DOM
}

String.Format alternative in C++

As already mentioned the C++ way is using stringstreams.

#include <sstream>

string a = "test";
string b = "text.txt";
string c = "text1.txt";

std::stringstream ostr;
ostr << a << " " << b << " > " << c;

Note that you can get the C string from the string stream object like so.

std::string formatted_string = ostr.str();
const char* c_str = formatted_string.c_str();

How to pad a string to a fixed length with spaces in Python?

name = "John" // your variable
result = (name+"               ")[:15] # this adds 15 spaces to the "name"
                                       # but cuts it at 15 characters

JDBC connection failed, error: TCP/IP connection to host failed

As the error says, you need to make sure that your sql server is running and listening on port 1433. If server is running then you need to check whether there is some firewall rule rejecting the connection on port 1433.

Here are the commands that can be useful to troubleshoot:

  1. Use netstat -a to check whether sql server is listening on the desired port
  2. As gerrytan mentioned in answer, you can try to do the telnet on the host and port

Installing RubyGems in Windows

Another way is to let chocolatey manage your ruby package (and any other package), that way you won't have to put ruby in your path manually:

Install chocolatey first by opening your favourite command prompt and executing:

@powershell -NoProfile -ExecutionPolicy unrestricted -Command "iex ((new-object net.webclient).DownloadString('https://chocolatey.org/install.ps1'))" && SET PATH=%PATH%;%systemdrive%\chocolatey\bin

then all you need to do is type

cinst ruby

In your command prompt and the package installs.

Using a package manager provides overall more control, I'd recommend this for every package that can be installed via chocolatey.

How to start Spyder IDE on Windows

After pip install spyder give this command

pip install --upgrade spyder

This command will update all Spyder dependencies.

Now in command prompt(cmd) navigate to the scripts folder in your python directory. In my system the path is C:\Users\win10\AppData\Local\Programs\Python\Python36-32\Scripts so i use the following command in command prompt.

cd C:\Users\win10\AppData\Local\Programs\Python\Python36-32\Scripts

once you are inside scripts directory type spyder3 and press enter and spyder ide starts.

C:\Users\win10\AppData\Local\Programs\Python\Python36-32\Scripts>spyder3

Using jQuery how to get click coordinates on the target element

Try this:

jQuery(document).ready(function(){
   $("#special").click(function(e){
      $('#status2').html(e.pageX +', '+ e.pageY);
   }); 
})

Here you can find more info with DEMO

Check if an excel cell exists on another worksheet in a column - and return the contents of a different column

You can use following formulas.

For Excel 2007 or later:

=IFERROR(VLOOKUP(D3,List!A:C,3,FALSE),"No Match")

For Excel 2003:

=IF(ISERROR(MATCH(D3,List!A:A, 0)), "No Match", VLOOKUP(D3,List!A:C,3,FALSE))

Note, that

  • I'm using List!A:C in VLOOKUP and returns value from column ? 3
  • I'm using 4th argument for VLOOKUP equals to FALSE, in that case VLOOKUP will only find an exact match, and the values in the first column of List!A:C do not need to be sorted (opposite to case when you're using TRUE).

ASP.NET email validator regex

I don't validate email address format anymore (Ok I check to make sure there is an at sign and a period after that). The reason for this is what says the correctly formatted address is even their email? You should be sending them an email and asking them to click a link or verify a code. This is the only real way to validate an email address is valid and that a person is actually able to recieve email.

How to convert CSV to JSON in Node.js

If you want just a command line converter, the quickest and most clean solution for me is to use csvtojson via npx (included by default in node.js)

$ npx csvtojson ./data.csv > data.json

How to make ConstraintLayout work with percentage values?

How to use Guidelines

The accepted answer is a little unclear about how to use guidelines and what the "header" is.

Steps

First add a Guideline.

enter image description here

Select the Guidline or move it a little bit to make the constraints visible.

enter image description here

Then click the round circle (the "header") until it becomes a percent. You can then drag this percentage down to 50% or whatever you want.

enter image description here

After that you can constrain your view to the Guideline to make it some percentage of the parent (using match_constraint on the view).

enter image description here

jquery $(this).id return Undefined

Hiya demo http://jsfiddle.net/LYTbc/

this is a reference to the DOM element, so you can wrap it directly.

attr api: http://api.jquery.com/attr/

The .attr() method gets the attribute value for only the first element in the matched set.

have a nice one, cheers!

code

$(document).ready(function () {
    $(".inputs").click(function () {
         alert(this.id);

        alert(" or " + $(this).attr("id"));

    });

});?

Running vbscript from batch file

Batch files are processed row by row and terminate whenever you call an executable directly.
- To make the batch file wait for the process to terminate and continue, put call in front of it.
- To make the batch file continue without waiting, put start "" in front of it.

I recommend using this single line script to accomplish your goal:

@call cscript "%~dp0necdaily.vbs"

(because this is a single line, you can use @ instead of @echo off)

If you believe your script can only be called from the SysWOW64 versions of cmd.exe, you might try:

@%WINDIR%\SysWOW64\cmd.exe /c call cscript "%~dp0necdaily.vbs"

If you need the window to remain, you can replace /c with /k

Make XAMPP / Apache serve file outside of htdocs folder

Solution to allow Apache 2 to host websites outside of htdocs:

Underneath the "DocumentRoot" directive in httpd.conf, you should see a directory block. Replace this directory block with:

<Directory />
    Options FollowSymLinks
    AllowOverride All
    Allow from all
</Directory> 

REMEMBER NOT TO USE THIS CONFIGURATION IN A REAL ENVIRONMENT

Using pickle.dump - TypeError: must be str, not bytes

The output file needs to be opened in binary mode:

f = open('varstor.txt','w')

needs to be:

f = open('varstor.txt','wb')

Inline list initialization in VB.NET

Collection initializers are only available in VB.NET 2010, released 2010-04-12:

Dim theVar = New List(Of String) From { "one", "two", "three" }

VBA Macro to compare all cells of two Excel files

A very simple check you can do with Cell formulas:

Sheet 1 (new - old)

=(if(AND(Ref_New<>"";Ref_Old="");Ref_New;"")

Sheet 2 (old - new)

=(if(AND(Ref_Old<>"";Ref_New="");Ref_Old;"")

This formulas should work for an ENGLISH Excel. For other languages they need to be translated. (For German i can assist)

You need to open all three Excel Documents, then copy the first formula into A1 of your sheet 1 and the second into A1 of sheet 2. Now click in A1 of the first cell and mark "Ref_New", now you can select your reference, go to the new file and click in the A1, go back to sheet1 and do the same for "Ref_Old" with the old file. Replace also the other "Ref_New".

Doe the same for Sheet two.

Now copy the formaula form A1 over the complete range where zour data is in the old and the new file.

But two cases are not covered here:

  1. In the compared cell of New and Old is the same data (Resulting Cell will be empty)
  2. In the compared cell of New and Old is diffe data (Resulting Cell will be empty)

To cover this two cases also, you should create your own function, means learn VBA. A very useful Excel page is cpearson.com

Rename all files in a folder with a prefix in a single command

Try the rename command in the folder with the files:

rename 's/^/Unix_/' *

The argument of rename (sed s command) indicates to replace the regex ^ with Unix_. The caret (^) is a special character that means start of the line.

What difference between the DATE, TIME, DATETIME, and TIMESTAMP Types

DATE: It is used for values with a date part but no time part. MySQL retrieves and displays DATE values in YYYY-MM-DD format. The supported range is 1000-01-01 to 9999-12-31.

DATETIME: It is used for values that contain both date and time parts. MySQL retrieves and displays DATETIME values in YYYY-MM-DD HH:MM:SS format. The supported range is 1000-01-01 00:00:00 to 9999-12-31 23:59:59.

TIMESTAMP: It is also used for values that contain both date and time parts, and includes the time zone. TIMESTAMP has a range of 1970-01-01 00:00:01 UTC to 2038-01-19 03:14:07 UTC.

TIME: Its values are in HH:MM:SS format (or HHH:MM:SS format for large hours values). TIME values may range from -838:59:59 to 838:59:59. The hours part may be so large because the TIME type can be used not only to represent a time of day (which must be less than 24 hours), but also elapsed time or a time interval between two events (which may be much greater than 24 hours, or even negative).

"unadd" a file to svn before commit

For Files - svn revert filename

For Folders - svn revert -R folder

check if command was successful in a batch file

Most commands/programs return a 0 on success and some other value, called errorlevel, to signal an error.

You can check for this in you batch for example by:

call <THE_COMMAND_HERE>
if %ERRORLEVEL% == 0 goto :next
echo "Errors encountered during execution.  Exited with status: %errorlevel%"
goto :endofscript

:next
echo "Doing the next thing"

:endofscript
echo "Script complete"

Pip error: Microsoft Visual C++ 14.0 is required

Pycrypto has vulnerabilities assigned the CVE-2013-7459 number, and the repo hasn't accept PRs since June 23, 2014.

Pycryptodome is a drop-in replacement for the PyCrypto library, which exposes almost the same API as the old PyCrypto, see Compatibility with PyCrypto.

If you haven't install pycrypto yet, you can use pip install pycryptodome to install pycryptodome in which you won't get Microsoft Visual C++ 14.0 issue.

Adding a directory to PATH in Ubuntu

you can set it in .bashrc

PATH=$PATH:/opt/ActiveTcl-8.5/bin;export PATH;

Center form submit buttons HTML / CSS

Input elements are inline by default. Add display:block to get the margins to apply. This will, however, break the buttons onto two separate lines. Use a wrapping <div> with text-align: center as suggested by others to get them on the same line.

Move all files except one

How about:

mv $(echo * | sed s:Tux.png::g) ~/Linux/New/

You have to be in the folder though.

Stopping an Android app from console

you can use the following from the device console: pm disable com.my.app.package which will kill it. Then use pm enable com.my.app.package so that you can launch it again.