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IIS Express gives Access Denied error when debugging ASP.NET MVC

In my case a previous run of my app from VS reserved the URL. I could see this by running in a console:

netsh http show urlacl

to delete this reservation i ran this in an elevated console:

netsh http delete urlacl http://127.0.0.1:10002/

I found these steps here solved my problem.

I'm using VS2013

Correct format specifier to print pointer or address?

You can use %x or %X or %p; all of them are correct.

  • If you use %x, the address is given as lowercase, for example: a3bfbc4
  • If you use %X, the address is given as uppercase, for example: A3BFBC4

Both of these are correct.

If you use %x or %X it's considering six positions for the address, and if you use %p it's considering eight positions for the address. For example:

Set folder for classpath

If you are using Java 6 or higher you can use wildcards of this form:

java -classpath ".;c:\mylibs\*;c:\extlibs\*" MyApp

If you would like to add all subdirectories: lib\a\, lib\b\, lib\c\, there is no mechanism for this in except:

java -classpath ".;c:\lib\a\*;c:\lib\b\*;c:\lib\c\*" MyApp

There is nothing like lib\*\* or lib\** wildcard for the kind of job you want to be done.

How to pass macro definition from "make" command line arguments (-D) to C source code?

Find the C file and Makefile implementation in below to meet your requirements

foo.c

 main ()
    {
        int a = MAKE_DEFINE;
        printf ("MAKE_DEFINE value:%d\n", a);
    }

Makefile

all:
    gcc -DMAKE_DEFINE=11 foo.c

Unable to find velocity template resources

VelocityEngine velocityEngin = new VelocityEngine();
velocityEngin.setProperty(RuntimeConstants.RESOURCE_LOADER, "classpath");
velocityEngin.setProperty("classpath.resource.loader.class", ClasspathResourceLoader.class.getName());

velocityEngin.init();

Template template = velocityEngin.getTemplate("nameOfTheTemplateFile.vtl");

you could use the above code to set the properties for velocity template. You can then give the name of the tempalte file when initializing the Template and it will find if it exists in the classpath.

All the above classes come from package org.apache.velocity*

Twitter Bootstrap dropdown menu

It's also possible to customise your bootstrap build by using:

http://twitter.github.com/bootstrap/customize.html

All the plugins are included by default.

Java path..Error of jvm.cfg

If you have installed more than one jdk version , uninstall the others and keep only the one in use. this worked for me. https://www.java.com/en/download/help/uninstall_java.xml

How can I remove all files in my git repo and update/push from my local git repo?

Remove all files not belonging to a repositiory (e.g. for a clean-build after switching a branch):

 git status | xargs rm -rf

Can you append strings to variables in PHP?

In PHP use .= to append strings, and not +=.

Why does this output 0? [...] Does PHP not like += with strings?

+= is an arithmetic operator to add a number to another number. Using that operator with strings leads to an automatic type conversion. In the OP's case the strings have been converted to integers of the value 0.


More about operators in PHP:

Using quotation marks inside quotation marks

Use the literal escape character \

print("Here is, \"a quote\"")

The character basically means ignore the semantic context of my next charcter, and deal with it in its literal sense.

Selecting last element in JavaScript array

This worked:

array.reverse()[0]

Eclipse error: "Editor does not contain a main type"

Try closing and reopening the file, then press Ctrl+F11.

Verify that the name of the file you are running is the same as the name of the project you are working in, and that the name of the public class in that file is the same as the name of the project you are working in as well.

Otherwise, restart Eclipse. Let me know if this solves the problem! Otherwise, comment, and I'll try and help.

How to get values from selected row in DataGrid for Windows Form Application?

You could just use

DataGridView1.CurrentRow.Cells["ColumnName"].Value

Extract names of objects from list

You can just use:

> names(LIST)
[1] "A" "B"

Obviously the names of the first element is just

> names(LIST)[1]
[1] "A"

Can I use Twitter Bootstrap and jQuery UI at the same time?

Yes you can use both. js bootstrap from twitter is a collection of jquery plugins. There shohuldn't be any conflict with jQuery UI.

Regarding bandwidth overload, it really depends on how you handle the requests to load all of your js files. if you really dont want to make multiple requests to the server to request for each file, just append them together and minimize. Or you probably can get rid of some js bootstrap plugins you dont need. it is very modular.

How do I call a function twice or more times consecutively?

Here is an approach that doesn't require the use of a for loop or defining an intermediate function or lambda function (and is also a one-liner). The method combines the following two ideas:

Putting these together, we get:

next(islice(iter(do, object()), 3, 3), None)

(The idea to pass object() as the sentinel comes from this accepted Stack Overflow answer.)

And here is what this looks like from the interactive prompt:

>>> def do():
...   print("called")
... 
>>> next(itertools.islice(iter(do, object()), 3, 3), None)
called
called
called

How to change the color of an image on hover

Use the background-color property instead of the background property in your CSS. So your code will look like this:
.fb-icon:hover {
background: blue;
}

Node JS Error: ENOENT

if your tmp folder is relative to the directory where your code is running remove the / in front of /tmp.

So you just have tmp/test.jpg in your code. This worked for me in a similar situation.

XAMPP permissions on Mac OS X?

You can also simply change Apache Conf file to a different User Name and keep the group:

Apache Conf Applications/Xammp/etc/..

User 'User' = your user name in Mac os x.

Group daemon

sudo chown -R 'User':daemon ~/Sites/wordpress 

sudo chmod -R g+w ~/Sites/wordpress

Get event listeners attached to node using addEventListener

You can obtain all jQuery events using $._data($('[selector]')[0],'events'); change [selector] to what you need.

There is a plugin that gather all events attached by jQuery called eventsReport.

Also i write my own plugin that do this with better formatting.

But anyway it seems we can't gather events added by addEventListener method. May be we can wrap addEventListener call to store events added after our wrap call.

It seems the best way to see events added to an element with dev tools.

But you will not see delegated events there. So there we need jQuery eventsReport.

UPDATE: NOW We CAN see events added by addEventListener method SEE RIGHT ANSWER TO THIS QUESTION.

Convert a PHP script into a stand-alone windows executable

The current PHP Nightrain (4.0.0) is written in Python and it uses the wxPython libraries. So far wxPython has been working well to get PHP Nightrain where it is today but in order to push PHP Nightrain to its next level, we are introducing a sibling of PHP Nightrain, the PHPWebkit!

It's an update to PHP Nightrain.

https://github.com/entrypass/nightrain-ep

The real difference between "int" and "unsigned int"

Hehe. You have an implicit cast here, because you're telling printf what type to expect.

Try this on for size instead:

unsigned int x = 0xFFFFFFFF;
int y = 0xFFFFFFFF;

if (x < 0)
    printf("one\n");
else
    printf("two\n");
if (y < 0)
    printf("three\n");
else
    printf("four\n");

How to create an android app using HTML 5

Try Sencha Touch. It is a HTML5 compliant framework to build application for touch devices.

How do I uninstall nodejs installed from pkg (Mac OS X)?

A little convenience script expanding on previous answers.

#!/bin/bash

# Uninstall node.js
# 
# Options:
#
# -d Actually delete files, otherwise the script just _prints_ a command to delete.
# -p Installation prefix. Default /usr/local
# -f BOM file. Default /var/db/receipts/org.nodejs.pkg.bom

CMD="echo sudo rm -fr"
BOM_FILE="/var/db/receipts/org.nodejs.pkg.bom"
PREFIX="/usr/local"

while getopts "dp:f:" arg; do
    case $arg in
        d)
            CMD="sudo rm -fr"
            ;;
        p)
            PREFIX=$arg
            ;;
        f)
            BOM_FILE=$arg
            ;;
    esac
done

lsbom -f -l -s -pf ${BOM_FILE} \
    | while read i; do
          $CMD ${PREFIX}/${i}
      done

$CMD ${PREFIX}/lib/node \
     ${PREFIX}/lib/node_modules \
     ${BOM_FILE}

Save it to file and run with:

# bash filename.sh

How to correct indentation in IntelliJ

Ctrl + Alt + L works with Android Studio under xfce4 on Linux. I see that Gnome used to use this shortcut for lock screen, but in Gnome 3 it was changed to Super+L (AKA Windows+L): https://wiki.gnome.org/Design/OS/KeyboardShortcuts

How to add minutes to my Date

you can use DateUtils class in org.apache.commons.lang3.time package

int addMinuteTime = 5;
Date targetTime = new Date(); //now
targetTime = DateUtils.addMinutes(targetTime, addMinuteTime); //add minute

Regex to match words of a certain length

Length of characters to be matched.

{n,m}  n <= length <= m
{n}    length == n
{n,}   length >= n

And by default, the engine is greedy to match this pattern. For example, if the input is 123456789, \d{2,5} will match 12345 which is with length 5.

If you want the engine returns when length of 2 matched, use \d{2,5}?

Regex that matches integers in between whitespace or start/end of string only

This just allow positive integers.

^[0-9]*[1-9][0-9]*$

OpenCV Python rotate image by X degrees around specific point

import numpy as np
import cv2

def rotate_image(image, angle):
  image_center = tuple(np.array(image.shape[1::-1]) / 2)
  rot_mat = cv2.getRotationMatrix2D(image_center, angle, 1.0)
  result = cv2.warpAffine(image, rot_mat, image.shape[1::-1], flags=cv2.INTER_LINEAR)
  return result

Assuming you're using the cv2 version, that code finds the center of the image you want to rotate, calculates the transformation matrix and applies to the image.

Throwing exceptions in a PHP Try Catch block

Throw needs an object instantiated by \Exception. Just the $e catched can play the trick.

throw $e

How to fix error ::Format of the initialization string does not conform to specification starting at index 0::

I have wasted 1.5 working days on this error and in the end a coworker solved the issue by replacing User Id by Uid and password by Pwd. The updated connection string for .Net was the error for me

Finding the average of a list

Combining a couple of the above answers, I've come up with the following which works with reduce and doesn't assume you have L available inside the reducing function:

from operator import truediv

L = [15, 18, 2, 36, 12, 78, 5, 6, 9]

def sum_and_count(x, y):
    try:
        return (x[0] + y, x[1] + 1)
    except TypeError:
        return (x + y, 2)

truediv(*reduce(sum_and_count, L))

# prints 
20.11111111111111

How to send a simple email from a Windows batch file?

I've used Blat ( http://www.blat.net/ ) for many years. It's a simple command line utility that can send email from command line. It's free and opensource.

You can use command like "Blat myfile.txt -to [email protected] -server smtp.domain.com -port 6000"

Here is some other software you can try to send email from command line (I've never used them):
http://caspian.dotconf.net/menu/Software/SendEmail/
http://www.petri.co.il/sendmail.htm
http://www.petri.co.il/software/mailsend105.zip
http://retired.beyondlogic.org/solutions/cmdlinemail/cmdlinemail.htm

Here ( http://www.petri.co.il/send_mail_from_script.htm ) you can find other various way of sending email from a VBS script, plus link to some of the mentioned software

The following VBScript code is taken from that page

Set objEmail = CreateObject("CDO.Message")
objEmail.From = "[email protected]"
objEmail.To = "[email protected]"
objEmail.Subject = "Server is down!"
objEmail.Textbody = "Server100 is no longer accessible over the network."
objEmail.Send

Save the file as something.vbs

Set Msg = CreateObject("CDO.Message")

With Msg

 .To = "[email protected]"
 .From = "[email protected]"
 .Subject = "Hello"
 .TextBody = "Just wanted to say hi."
 .Send

End With

Save the file as something2.vbs

I think these VBS scripts use the windows default mail server, if present. I've not tested these scripts...

Detect if device is iOS

var isiOSSafari = (navigator.userAgent.match(/like Mac OS X/i)) ? true: false;

MongoDB: update every document on one field

This code will be helpful for you

        Model.update({
            'type': "newuser"
        }, {
            $set: {
                email: "[email protected]",
                phoneNumber:"0123456789"
            }
        }, {
            multi: true
        },
        function(err, result) {
            console.log(result);
            console.log(err);
        })  

Regular Expression for any number greater than 0?

You can use the below expression:

(^\d*\.?\d*[1-9]+\d*$)|(^[1-9]+\.?\d*$)                  

Valid entries: 1 1. 1.1 1.0 all positive real numbers

Invalid entries: all negative real numbers and 0 and 0.0

Convert object string to JSON

var str = "{ hello: 'world', places: ['Africa', 'America', 'Asia', 'Australia'] }" var fStr = str .replace(/([A-z]*)(:)/g, '"$1":') .replace(/'/g, "\"")

console.log(JSON.parse(fStr))enter image description here

Sorry I am on my phone, here is a pic.

How do I add a submodule to a sub-directory?

You go into ~/.janus and run:

git submodule add <git@github ...> snipmate-snippets/snippets/

If you need more information about submodules (or git in general) ProGit is pretty useful.

How to check task status in Celery?

I found helpful information in the

Celery Project Workers Guide inspecting-workers

For my case, I am checking to see if Celery is running.

inspect_workers = task.app.control.inspect()
if inspect_workers.registered() is None:
    state = 'FAILURE'
else:
    state = str(task.state) 

You can play with inspect to get your needs.

Removing a Fragment from the back stack

You add to the back state from the FragmentTransaction and remove from the backstack using FragmentManager pop methods:

FragmentManager manager = getActivity().getSupportFragmentManager();
FragmentTransaction trans = manager.beginTransaction();
trans.remove(myFrag);
trans.commit();
manager.popBackStack();

Check if a string within a list contains a specific string with Linq

I think you want Any:

if (myList.Any(str => str.Contains("Mdd LH")))

It's well worth becoming familiar with the LINQ standard query operators; I would usually use those rather than implementation-specific methods (such as List<T>.ConvertAll) unless I was really bothered by the performance of a specific operator. (The implementation-specific methods can sometimes be more efficient by knowing the size of the result etc.)

How to select only date from a DATETIME field in MySQL?

Please try this answer.

SELECT * FROM `Yourtable` WHERE date(`dateField`) = '2018-09-25'

Arrays in cookies PHP

Serialize data:

setcookie('cookie', serialize($info), time()+3600);

Then unserialize data:

$data = unserialize($_COOKIE['cookie'], ["allowed_classes" => false]);

After data, $info and $data will have the same content.

How to declare or mark a Java method as deprecated?

since some minor explanations were missing

Use @Deprecated annotation on the method like this

 /**
 * @param basePrice
 * 
 * @deprecated  reason this method is deprecated <br/>
 *              {will be removed in next version} <br/>
 *              use {@link #setPurchasePrice()} instead like this: 
 * 
 * 
 * <blockquote><pre>
 * getProduct().setPurchasePrice(200) 
 * </pre></blockquote>
 * 
 */
@Deprecated
public void setBaseprice(int basePrice) {
}

remember to explain:

  1. Why is this method no longer recommended. What problems arise when using it. Provide a link to the discussion on the matter if any. (remember to separate lines for readability <br/>
  2. When it will be removed. (let your users know how much they can still rely on this method if they decide to stick to the old way)
  3. Provide a solution or link to the method you recommend {@link #setPurchasePrice()}

Hide all warnings in ipython

I hide the warnings in the pink boxes by running the following code in a cell:

from IPython.display import HTML
HTML('''<script>
code_show_err=false; 
function code_toggle_err() {
 if (code_show_err){
 $('div.output_stderr').hide();
 } else {
 $('div.output_stderr').show();
 }
 code_show_err = !code_show_err
} 
$( document ).ready(code_toggle_err);
</script>
To toggle on/off output_stderr, click <a href="javascript:code_toggle_err()">here</a>.''')

How to SELECT WHERE NOT EXIST using LINQ?

How about..

var result = (from s in context.Shift join es in employeeshift on s.shiftid equals es.shiftid where es.empid == 57 select s)

Edit: This will give you shifts where there is an associated employeeshift (because of the join). For the "not exists" I'd do what @ArsenMkrt or @hyp suggest

ClassNotFoundException: org.slf4j.LoggerFactory

Better to always download as your first try, the most recent version from the developer's site

I had the same error message you had, and by downloading the jar from the above (slf4j-1.7.2.tar.gz most recent version as of 2012OCT13), untarring, uncompressing, adding 2 jars to build path in eclipse (or adding to classpath in comand line):

  1. slf4j-api-1.7.2.jar
  2. slf4j-simple-1.7.2.jar

I was able to run my program.

new Runnable() but no new thread?

Runnable is often used to provide the code that a thread should run, but Runnable itself has nothing to do with threads. It's just an object with a run() method.

In Android, the Handler class can be used to ask the framework to run some code later on the same thread, rather than on a different one. Runnable is used to provide the code that should run later.

How to extract HTTP response body from a Python requests call?


import requests

site_request = requests.get("https://abhiunix.in")

site_response = str(site_request.content)

print(site_response)

You can do it either way.

How to run an android app in background?

As apps run in the background anyway. I’m assuming what your really asking is how do you make apps do stuff in the background. The solution below will make your app do stuff in the background after opening the app and after the system has rebooted.

Below, I’ve added a link to a fully working example (in the form of an Android Studio Project)

This subject seems to be out of the scope of the Android docs, and there doesn’t seem to be any one comprehensive doc on this. The information is spread across a few docs.

The following docs tell you indirectly how to do this: https://developer.android.com/reference/android/app/Service.html

https://developer.android.com/reference/android/content/BroadcastReceiver.html

https://developer.android.com/guide/components/bound-services.html

In the interests of getting your usage requirements correct, the important part of this above doc to read carefully is: #Binder, #Messenger and the components link below:

https://developer.android.com/guide/components/aidl.html

Here is the link to a fully working example (in Android Studio format): http://developersfound.com/BackgroundServiceDemo.zip

This project will start an Activity which binds to a service; implementing the AIDL.

This project is also useful to re-factor for the purpose of IPC across different apps.

This project is also developed to start automatically when Android restarts (provided the app has been run at least one after installation and app is not installed on SD card)

When this app/project runs after reboot, it dynamically uses a transparent view to make it look like no app has started but the service of the associated app starts cleanly.

This code is written in such a way that it’s very easy to tweak to simulate a scheduled service.

This project is developed in accordance to the above docs and is subsequently a clean solution.

There is however a part of this project which is not clean being: I have not found a way to start a service on reboot without using an Activity. If any of you guys reading this post have a clean way to do this please post a comment.

Predict() - Maybe I'm not understanding it

Thanks Hong, that was exactly the problem I was running into. The error you get suggests that the number of rows is wrong, but the problem is actually that the model has been trained using a command that ends up with the wrong names for parameters.

This is really a critical detail that is entirely non-obvious for lm and so on. Some of the tutorial make reference to doing lines like lm(olive$Area@olive$Palmitic) - ending up with variable names of olive$Area NOT Area, so creating an entry using anewdata<-data.frame(Palmitic=2) can't then be used. If you use lm(Area@Palmitic,data=olive) then the variable names are right and prediction works.

The real problem is that the error message does not indicate the problem at all:

Warning message: 'anewdata' had 1 rows but variable(s) found to have X rows

How To Change DataType of a DataColumn in a DataTable?

I combined the efficiency of Mark's solution - so I do not have to .Clone the entire DataTable - with generics and extensibility, so I can define my own conversion function. This is what I ended up with:

/// <summary>
///     Converts a column in a DataTable to another type using a user-defined converter function.
/// </summary>
/// <param name="dt">The source table.</param>
/// <param name="columnName">The name of the column to convert.</param>
/// <param name="valueConverter">Converter function that converts existing values to the new type.</param>
/// <typeparam name="TTargetType">The target column type.</typeparam>
public static void ConvertColumnTypeTo<TTargetType>(this DataTable dt, string columnName, Func<object, TTargetType> valueConverter)
{
    var newType = typeof(TTargetType);

    DataColumn dc = new DataColumn(columnName + "_new", newType);

    // Add the new column which has the new type, and move it to the ordinal of the old column
    int ordinal = dt.Columns[columnName].Ordinal;
    dt.Columns.Add(dc);
    dc.SetOrdinal(ordinal);

    // Get and convert the values of the old column, and insert them into the new
    foreach (DataRow dr in dt.Rows)
    {
        dr[dc.ColumnName] = valueConverter(dr[columnName]);
    }

    // Remove the old column
    dt.Columns.Remove(columnName);

    // Give the new column the old column's name
    dc.ColumnName = columnName;
}

This way, usage is a lot more straightforward, while also customizable:

DataTable someDt = CreateSomeDataTable();
// Assume ColumnName is an int column which we want to convert to a string one.
someDt.ConvertColumnTypeTo<string>('ColumnName', raw => raw.ToString());

How to convert milliseconds to "hh:mm:ss" format?

 public String millsToDateFormat(long mills) {

    Date date = new Date(mills);
    DateFormat formatter = new SimpleDateFormat("HH:mm:ss");
    String dateFormatted = formatter.format(date);
    return dateFormatted; //note that it will give you the time in GMT+0
}

What does %s and %d mean in printf in the C language?

The printf() family of functions uses % character as a placeholder. When a % is encountered, printf reads the characters following the % to determine what to do:

%s - Take the next argument and print it as a string
%d - Take the next argument and print it as an int

See this Wikipedia article for a nice picture: printf format string

The \n at the end of the string is for a newline/carriage-return character.

Check for database connection, otherwise display message

Try this:

<?php
$servername   = "localhost";
$database = "database";
$username = "user";
$password = "password";

// Create connection
$conn = new mysqli($servername, $username, $password, $database);
// Check connection
if ($conn->connect_error) {
   die("Connection failed: " . $conn->connect_error);
}
  echo "Connected successfully";
?>

R: numeric 'envir' arg not of length one in predict()

There are several problems here:

  1. The newdata argument of predict() needs a predictor variable. You should thus pass it values for Coupon, instead of Total, which is the response variable in your model.

  2. The predictor variable needs to be passed in as a named column in a data frame, so that predict() knows what the numbers its been handed represent. (The need for this becomes clear when you consider more complicated models, having more than one predictor variable).

  3. For this to work, your original call should pass df in through the data argument, rather than using it directly in your formula. (This way, the name of the column in newdata will be able to match the name on the RHS of the formula).

With those changes incorporated, this will work:

model <- lm(Total ~ Coupon, data=df)
new <- data.frame(Coupon = df$Coupon)
predict(model, newdata = new, interval="confidence")

How do I import modules or install extensions in PostgreSQL 9.1+?

How to download and install if you have SUSE. As an example I am downloading the tablefunc module so I can use crosstab. I have PostgreSQL 9.6.1.

right-click desktop, terminal, type:

sudo zypper in postgreql-contrib

Enter credentials, continue by typing:

y

Run query (I ran mine from pgAdminIII):

CREATE EXTENSION tablefunc;

You should now have the crosstab function.

I did not have to restart.

Sorting a vector in descending order

Instead of a functor as Mehrdad proposed, you could use a Lambda function.

sort(numbers.begin(), numbers.end(), [](const int a, const int b) {return a > b; });

CentOS: Enabling GD Support in PHP Installation

With CentOS 6.5+ and PHP 5.5:

yum install php55u-gd
service httpd restart

If you get an error like: cannot map zero-fill pages: Cannot allocate memory in Unknown on line 0, it could be because you don't have a swap file. I suggest you take a look at the tutorial mentioned in this answer: https://stackoverflow.com/a/20275282/828366

Tutorial: https://www.digitalocean.com/community/articles/how-to-add-swap-on-centos-6

How do I put double quotes in a string in vba?

I have written a small routine which copies formula from a cell to clipboard which one can easily paste in Visual Basic Editor.

    Public Sub CopyExcelFormulaInVBAFormat()
        Dim strFormula As String
        Dim objDataObj As Object

        '\Check that single cell is selected!
       If Selection.Cells.Count > 1 Then
            MsgBox "Select single cell only!", vbCritical
            Exit Sub
        End If

        'Check if we are not on a blank cell!
       If Len(ActiveCell.Formula) = 0 Then
            MsgBox "No Formula To Copy!", vbCritical
            Exit Sub
        End If

        'Add quotes as required in VBE
       strFormula = Chr(34) & Replace(ActiveCell.Formula, Chr(34), Chr(34) & Chr(34)) & Chr(34)

        'This is ClsID of MSFORMS Data Object
       Set objDataObj = CreateObject("New:{1C3B4210-F441-11CE-B9EA-00AA006B1A69}")
        objDataObj.SetText strFormula, 1
        objDataObj.PutInClipboard
        MsgBox "VBA Format formula copied to Clipboard!", vbInformation

        Set objDataObj = Nothing

    End Sub

It is originally posted on Chandoo.org forums' Vault Section.

How do I resolve "Cannot find module" error using Node.js?

Please install the new CLI v3 (npm install -g ionic@latest).

If this issue is still a problem in CLI v3. Thank you!

TypeError: unhashable type: 'numpy.ndarray'

numpy.ndarray can contain any type of element, e.g. int, float, string etc. Check the type an do a conversion if neccessary.

Access cell value of datatable

If you need a weak reference to the cell value:

object field = d.Rows[0][3]

or

object field = d.Rows[0].ItemArray[3]

Should do it

If you need a strongly typed reference (string in your case) you can use the DataRowExtensions.Field extension method:

string field = d.Rows[0].Field<string>(3);

(make sure System.Data is in listed in the namespaces in this case)

Indexes are 0 based so we first access the first row (0) and then the 4th column in this row (3)

Add MIME mapping in web.config for IIS Express

I know this is an old question, but...

I was just noticing my instance of IISExpress wasn't serving woff files, so I wen't searching (Found this) and then found:

http://www.tomasmcguinness.com/2011/07/06/adding-support-for-svg-to-iis-express/

I suppose my install has support for SVG since I haven't had issue with that. But the instructions are trivially modifiable for woff:

  • Open a console application with administrator privilages.
  • Navigation to the IIS Express directory. This lives under Program Files or Program Files (x86)
  • Run the command:

    appcmd set config /section:staticContent /+[fileExtension='woff',mimeType='application/x-woff']

Solved my problem, and I didn't have to mess with some crummy config (like I had to to add support for the PUT and DELETE verbs). Yay!

How can we run a test method with multiple parameters in MSTest?

MSTest does not support that feature, but you can implement your own attribute to achieve that.

Have a look at Enabling parameterized tests in MSTest using PostSharp.

How to check if mod_rewrite is enabled in php?

Use this function:

function apache_module_exists($module)
{
    return in_array($module, apache_get_modules());
}

How to create an installer for a .net Windows Service using Visual Studio

Nor Kelsey, nor Brendan solutions does not works for me in Visual Studio 2015 Community.

Here is my brief steps how to create service with installer:

  1. Run Visual Studio, Go to File->New->Project
  2. Select .NET Framework 4, in 'Search Installed Templates' type 'Service'
  3. Select 'Windows Service'. Type Name and Location. Press OK.
  4. Double click Service1.cs, right click in designer and select 'Add Installer'
  5. Double click ProjectInstaller.cs. For serviceProcessInstaller1 open Properties tab and change 'Account' property value to 'LocalService'. For serviceInstaller1 change 'ServiceName' and set 'StartType' to 'Automatic'.
  6. Double click serviceInstaller1. Visual Studio creates serviceInstaller1_AfterInstall event. Write code:

    private void serviceInstaller1_AfterInstall(object sender, InstallEventArgs e)
    {
        using (System.ServiceProcess.ServiceController sc = new 
        System.ServiceProcess.ServiceController(serviceInstaller1.ServiceName))
        {
            sc.Start();
        }
    }
    
  7. Build solution. Right click on project and select 'Open Folder in File Explorer'. Go to bin\Debug.

  8. Create install.bat with below script:

    :::::::::::::::::::::::::::::::::::::::::
    :: Automatically check & get admin rights
    :::::::::::::::::::::::::::::::::::::::::
    @echo off
    CLS 
    ECHO.
    ECHO =============================
    ECHO Running Admin shell
    ECHO =============================
    
    :checkPrivileges 
    NET FILE 1>NUL 2>NUL
    if '%errorlevel%' == '0' ( goto gotPrivileges ) else ( goto getPrivileges ) 
    
    :getPrivileges 
    if '%1'=='ELEV' (shift & goto gotPrivileges)  
    ECHO. 
    ECHO **************************************
    ECHO Invoking UAC for Privilege Escalation 
    ECHO **************************************
    
    setlocal DisableDelayedExpansion
    set "batchPath=%~0"
    setlocal EnableDelayedExpansion
    ECHO Set UAC = CreateObject^("Shell.Application"^) > "%temp%\OEgetPrivileges.vbs" 
    ECHO UAC.ShellExecute "!batchPath!", "ELEV", "", "runas", 1 >> "%temp%\OEgetPrivileges.vbs" 
    "%temp%\OEgetPrivileges.vbs" 
    exit /B 
    
    :gotPrivileges 
    ::::::::::::::::::::::::::::
    :START
    ::::::::::::::::::::::::::::
    setlocal & pushd .
    
    cd /d %~dp0
    %windir%\Microsoft.NET\Framework\v4.0.30319\InstallUtil /i "WindowsService1.exe"
    pause
    
  9. Create uninstall.bat file (change in pen-ult line /i to /u)
  10. To install and start service run install.bat, to stop and uninstall run uninstall.bat

Error Code: 1005. Can't create table '...' (errno: 150)

It happened in my case, because the name of the table being referenced in the constraint declaration wasn't correct (I forgot the upper case in the table name):

ALTER TABLE `Window` ADD CONSTRAINT `Windows_ibfk_1` FOREIGN KEY (`WallId`) REFERENCES `Wall` (`id`) ON DELETE CASCADE ON UPDATE CASCADE;

shift a std_logic_vector of n bit to right or left

This is typically done manually by choosing the appropriate bits from the vector and then appending 0s.

For example, to shift a vector 8 bits

variable tmp : std_logic_vector(15 downto 0)
...
tmp := x"00" & tmp(15 downto 8);

Hopefully this simple answer is useful to someone

How to compare two colors for similarity/difference

All methods below result in a scale from 0-100.

internal static class ColorDifference
{
    internal enum Method
    {
        Binary, // true or false, 0 is false
        Square,
        Dimensional,
        CIE76
    }

    public static double Calculate(Method method, int argb1, int argb2)
    {
        int[] c1 = ColorConversion.ArgbToArray(argb1);
        int[] c2 = ColorConversion.ArgbToArray(argb2);
        return Calculate(method, c1[1], c2[1], c1[2], c2[2], c1[3], c2[3], c1[0], c2[0]);
    }

    public static double Calculate(Method method, int r1, int r2, int g1, int g2, int b1, int b2, int a1 = -1, int a2 = -1)
    {
        switch (method)
        {
            case Method.Binary:
                return (r1 == r2 && g1 == g2 && b1 == b2 && a1 == a2) ? 0 : 100;
            case Method.CIE76:
                return CalculateCIE76(r1, r2, g1, g2, b1, b2);
            case Method.Dimensional:
                if (a1 == -1 || a2 == -1) return Calculate3D(r1, r2, g1, g2, b1, b2);
                else return Calculate4D(r1, r2, g1, g2, b1, b2, a1, a2);
            case Method.Square:
                return CalculateSquare(r1, r2, g1, g2, b1, b2, a1, a2);
            default:
                throw new InvalidOperationException();
        }
    }

    public static double Calculate(Method method, Color c1, Color c2, bool alpha)
    {
        switch (method)
        {
            case Method.Binary:
                return (c1.R == c2.R && c1.G == c2.G && c1.B == c2.B && (!alpha || c1.A == c2.A)) ? 0 : 100;
            case Method.CIE76:
                if (alpha) throw new InvalidOperationException();
                return CalculateCIE76(c1, c2);
            case Method.Dimensional:
                if (alpha) return Calculate4D(c1, c2);
                else return Calculate3D(c1, c2);
            case Method.Square:
                if (alpha) return CalculateSquareAlpha(c1, c2);
                else return CalculateSquare(c1, c2);
            default:
                throw new InvalidOperationException();
        }
    }

    // A simple idea, based on on a Square
    public static double CalculateSquare(int argb1, int argb2)
    {
        int[] c1 = ColorConversion.ArgbToArray(argb1);
        int[] c2 = ColorConversion.ArgbToArray(argb2);
        return CalculateSquare(c1[1], c2[1], c1[2], c2[2], c1[3], c2[3]);
    }

    public static double CalculateSquare(Color c1, Color c2)
    {
        return CalculateSquare(c1.R, c2.R, c1.G, c2.G, c1.B, c2.B);
    }

    public static double CalculateSquareAlpha(int argb1, int argb2)
    {
        int[] c1 = ColorConversion.ArgbToArray(argb1);
        int[] c2 = ColorConversion.ArgbToArray(argb2);
        return CalculateSquare(c1[1], c2[1], c1[2], c2[2], c1[3], c2[3], c1[0], c2[0]);
    }

    public static double CalculateSquareAlpha(Color c1, Color c2)
    {
        return CalculateSquare(c1.R, c2.R, c1.G, c2.G, c1.B, c2.B, c1.A, c2.A);
    }

    public static double CalculateSquare(int r1, int r2, int g1, int g2, int b1, int b2, int a1 = -1, int a2 = -1)
    {
        if (a1 == -1 || a2 == -1) return (Math.Abs(r1 - r2) + Math.Abs(g1 - g2) + Math.Abs(b1 - b2)) / 7.65;
        else return (Math.Abs(r1 - r2) + Math.Abs(g1 - g2) + Math.Abs(b1 - b2) + Math.Abs(a1 - a2)) / 10.2;
    }

    // from:http://stackoverflow.com/questions/9018016/how-to-compare-two-colors
    public static double Calculate3D(int argb1, int argb2)
    {
        int[] c1 = ColorConversion.ArgbToArray(argb1);
        int[] c2 = ColorConversion.ArgbToArray(argb2);
        return Calculate3D(c1[1], c2[1], c1[2], c2[2], c1[3], c2[3]);
    }

    public static double Calculate3D(Color c1, Color c2)
    {
        return Calculate3D(c1.R, c2.R, c1.G, c2.G, c1.B, c2.B);
    }

    public static double Calculate3D(int r1, int r2, int g1, int g2, int b1, int b2)
    {
        return Math.Sqrt(Math.Pow(Math.Abs(r1 - r2), 2) + Math.Pow(Math.Abs(g1 - g2), 2) + Math.Pow(Math.Abs(b1 - b2), 2)) / 4.41672955930063709849498817084;
    }

    // Same as above, but made 4D to include alpha channel
    public static double Calculate4D(int argb1, int argb2)
    {
        int[] c1 = ColorConversion.ArgbToArray(argb1);
        int[] c2 = ColorConversion.ArgbToArray(argb2);
        return Calculate4D(c1[1], c2[1], c1[2], c2[2], c1[3], c2[3], c1[0], c2[0]);
    }

    public static double Calculate4D(Color c1, Color c2)
    {
        return Calculate4D(c1.R, c2.R, c1.G, c2.G, c1.B, c2.B, c1.A, c2.A);
    }

    public static double Calculate4D(int r1, int r2, int g1, int g2, int b1, int b2, int a1, int a2)
    {
        return Math.Sqrt(Math.Pow(Math.Abs(r1 - r2), 2) + Math.Pow(Math.Abs(g1 - g2), 2) + Math.Pow(Math.Abs(b1 - b2), 2) + Math.Pow(Math.Abs(a1 - a2), 2)) / 5.1;
    }

    /**
    * Computes the difference between two RGB colors by converting them to the L*a*b scale and
    * comparing them using the CIE76 algorithm { http://en.wikipedia.org/wiki/Color_difference#CIE76}
    */
    public static double CalculateCIE76(int argb1, int argb2)
    {
        return CalculateCIE76(Color.FromArgb(argb1), Color.FromArgb(argb2));
    }

    public static double CalculateCIE76(Color c1, Color c2)
    {
        return CalculateCIE76(c1.R, c2.R, c1.G, c2.G, c1.B, c2.B);
    }

    public static double CalculateCIE76(int r1, int r2, int g1, int g2, int b1, int b2)
    {
        int[] lab1 = ColorConversion.ColorToLab(r1, g1, b1);
        int[] lab2 = ColorConversion.ColorToLab(r2, g2, b2);
        return Math.Sqrt(Math.Pow(lab2[0] - lab1[0], 2) + Math.Pow(lab2[1] - lab1[1], 2) + Math.Pow(lab2[2] - lab1[2], 2)) / 2.55;
    }
}


internal static class ColorConversion
{

    public static int[] ArgbToArray(int argb)
    {
        return new int[] { (argb >> 24), (argb >> 16) & 0xFF, (argb >> 8) & 0xFF, argb & 0xFF };
    }

    public static int[] ColorToLab(int R, int G, int B)
    {
        // http://www.brucelindbloom.com

        double r, g, b, X, Y, Z, fx, fy, fz, xr, yr, zr;
        double Ls, fas, fbs;
        double eps = 216.0f / 24389.0f;
        double k = 24389.0f / 27.0f;

        double Xr = 0.964221f;  // reference white D50
        double Yr = 1.0f;
        double Zr = 0.825211f;

        // RGB to XYZ
        r = R / 255.0f; //R 0..1
        g = G / 255.0f; //G 0..1
        b = B / 255.0f; //B 0..1

        // assuming sRGB (D65)
        if (r <= 0.04045) r = r / 12;
        else r = (float)Math.Pow((r + 0.055) / 1.055, 2.4);

        if (g <= 0.04045) g = g / 12;
        else g = (float)Math.Pow((g + 0.055) / 1.055, 2.4);

        if (b <= 0.04045) b = b / 12;
        else b = (float)Math.Pow((b + 0.055) / 1.055, 2.4);

        X = 0.436052025f * r + 0.385081593f * g + 0.143087414f * b;
        Y = 0.222491598f * r + 0.71688606f * g + 0.060621486f * b;
        Z = 0.013929122f * r + 0.097097002f * g + 0.71418547f * b;

        // XYZ to Lab
        xr = X / Xr;
        yr = Y / Yr;
        zr = Z / Zr;

        if (xr > eps) fx = (float)Math.Pow(xr, 1 / 3.0);
        else fx = (float)((k * xr + 16.0) / 116.0);

        if (yr > eps) fy = (float)Math.Pow(yr, 1 / 3.0);
        else fy = (float)((k * yr + 16.0) / 116.0);

        if (zr > eps) fz = (float)Math.Pow(zr, 1 / 3.0);
        else fz = (float)((k * zr + 16.0) / 116);

        Ls = (116 * fy) - 16;
        fas = 500 * (fx - fy);
        fbs = 200 * (fy - fz);

        int[] lab = new int[3];
        lab[0] = (int)(2.55 * Ls + 0.5);
        lab[1] = (int)(fas + 0.5);
        lab[2] = (int)(fbs + 0.5);
        return lab;
    }
}

exception.getMessage() output with class name

I think you are wrapping your exception in another exception (which isn't in your code above). If you try out this code:

public static void main(String[] args) {
    try {
        throw new RuntimeException("Cannot move file");
    } catch (Exception ex) {
        JOptionPane.showMessageDialog(null, "Error: " + ex.getMessage());
    }
}

...you will see a popup that says exactly what you want.


However, to solve your problem (the wrapped exception) you need get to the "root" exception with the "correct" message. To do this you need to create a own recursive method getRootCause:

public static void main(String[] args) {
    try {
        throw new Exception(new RuntimeException("Cannot move file"));
    } catch (Exception ex) {
        JOptionPane.showMessageDialog(null,
                                      "Error: " + getRootCause(ex).getMessage());
    }
}

public static Throwable getRootCause(Throwable throwable) {
    if (throwable.getCause() != null)
        return getRootCause(throwable.getCause());

    return throwable;
}

Note: Unwrapping exceptions like this however, sort of breaks the abstractions. I encourage you to find out why the exception is wrapped and ask yourself if it makes sense.

Define preprocessor macro through CMake?

For a long time, CMake had the add_definitions command for this purpose. However, recently the command has been superseded by a more fine grained approach (separate commands for compile definitions, include directories, and compiler options).

An example using the new add_compile_definitions:

add_compile_definitions(OPENCV_VERSION=${OpenCV_VERSION})
add_compile_definitions(WITH_OPENCV2)

Or:

add_compile_definitions(OPENCV_VERSION=${OpenCV_VERSION} WITH_OPENCV2)

The good part about this is that it circumvents the shabby trickery CMake has in place for add_definitions. CMake is such a shabby system, but they are finally finding some sanity.

Find more explanation on which commands to use for compiler flags here: https://cmake.org/cmake/help/latest/command/add_definitions.html

Likewise, you can do this per-target as explained in Jim Hunziker's answer.

Calculating how many minutes there are between two times

If the difference between endTime and startTime is greater than or equal to 60 Minutes , the statement:endTime.Subtract(startTime).Minutes; will always return (minutesDifference % 60). Obviously which is not desired when we are only talking about minutes (not hours here).
Here are some of the ways if you want to get total number of minutes(in different typecasts):

// Default value that is returned is of type *double* 
double double_minutes = endTime.Subtract(startTime).TotalMinutes; 
int integer_minutes = (int)endTime.Subtract(startTime).TotalMinutes; 
long long_minutes = (long)endTime.Subtract(startTime).TotalMinutes; 
string string_minutes = (string)endTime.Subtract(startTime).TotalMinutes; 

How to get primary key column in Oracle?

Select constraint_name,constraint_type from user_constraints where table_name** **= ‘TABLE_NAME’ ;

(This will list the primary key and then)

Select column_name,position from user_cons_cloumns where constraint_name=’PK_XYZ’; 

(This will give you the column, here PK_XYZ is the primay key name)

How to add 10 minutes to my (String) time?

Something like this

 String myTime = "14:10";
 SimpleDateFormat df = new SimpleDateFormat("HH:mm");
 Date d = df.parse(myTime); 
 Calendar cal = Calendar.getInstance();
 cal.setTime(d);
 cal.add(Calendar.MINUTE, 10);
 String newTime = df.format(cal.getTime());

As a fair warning there might be some problems if daylight savings time is involved in this 10 minute period.

how to rotate a bitmap 90 degrees

Using Java createBitmap() method you can pass the degrees.

Bitmap bInput /*your input bitmap*/, bOutput;
float degrees = 45; //rotation degree
Matrix matrix = new Matrix();
matrix.setRotate(degrees);
bOutput = Bitmap.createBitmap(bInput, 0, 0, bInput.getWidth(), bInput.getHeight(), matrix, true);

Looping through a hash, or using an array in PowerShell

About looping through a hash:

$Q = @{"ONE"="1";"TWO"="2";"THREE"="3"}
$Q.GETENUMERATOR() | % { $_.VALUE }
1
3
2

$Q.GETENUMERATOR() | % { $_.key }
ONE
THREE
TWO

How to run batch file from network share without "UNC path are not supported" message?

PUSHD and POPD should help in your case.

@echo off
:: Create a temporary drive letter mapped to your UNC root location
:: and effectively CD to that location
pushd \\server\soft

:: Do your work
WP15\setup.exe
robocopy.exe "WP15\Custom" /copyall "C:\Program Files (x86)\WP\Custom Templates"
Regedit.exe /s WPX5\Custom\Migrate.reg

:: Remove the temporary drive letter and return to your original location
popd

Type PUSHD /? from the command line for more information.

How to get the element clicked (for the whole document)?

$(document).click(function (e) {
    alert($(e.target).text());
});

If file exists then delete the file

IF both POS_History_bim_data_*.zip and POS_History_bim_data_*.zip.trg exists in  Y:\ExternalData\RSIDest\ Folder then Delete File Y:\ExternalData\RSIDest\Target_slpos_unzip_done.dat

Matplotlib (pyplot) savefig outputs blank image

Call plt.show() after plt.savefig(fig) and your problem should be solved.

Indentation shortcuts in Visual Studio

Tab to tab right, shift-tab to tab left.

python's re: return True if string contains regex pattern

You can do something like this:

Using search will return a SRE_match object, if it matches your search string.

>>> import re
>>> m = re.search(u'ba[r|z|d]', 'bar')
>>> m
<_sre.SRE_Match object at 0x02027288>
>>> m.group()
'bar'
>>> n = re.search(u'ba[r|z|d]', 'bas')
>>> n.group()

If not, it will return None

Traceback (most recent call last):
  File "<pyshell#17>", line 1, in <module>
    n.group()
AttributeError: 'NoneType' object has no attribute 'group'

And just to print it to demonstrate again:

>>> print n
None

NuGet Package Restore Not Working

The best workaround that I found creating a new Project from scratch, then import all the source files with the code. My project was not so complicated so I had no problem from there.

Regex to check whether a string contains only numbers

If you need just positive integer numbers and don't need leading zeros (e.g. "0001234" or "00"):

var reg = /^(?:[1-9]\d*|\d)$/;

For files in directory, only echo filename (no path)

Just use basename:

echo `basename "$filename"`

The quotes are needed in case $filename contains e.g. spaces.

Media Player called in state 0, error (-38,0)

  if(length>0)
        {
            mediaPlayer = new MediaPlayer();
            Log.d("length",""+length);
            try {
                mediaPlayer.setDataSource(getApplication(),Uri.parse(uri));
            } catch(IOException e) {
                e.printStackTrace();
            }
            mediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                @Override
                public void onPrepared(MediaPlayer mediaPlayer) {
                    mediaPlayer.seekTo(length);
                    mediaPlayer.start();

                }
            });
            mediaPlayer.prepareAsync();

How to find index position of an element in a list when contains returns true

benefit.indexOf(map4)

It either returns an index or -1 if the items is not found.

I strongly recommend wrapping the map in some object and use generics if possible.

How do I set GIT_SSL_NO_VERIFY for specific repos only?

You can do as follows

For a single repo

git config http.sslVerify false

For all repo

git config --global http.sslVerify false

Process all arguments except the first one (in a bash script)

Working in bash 4 or higher version:

#!/bin/bash
echo "$0";         #"bash"
bash --version;    #"GNU bash, version 5.0.3(1)-release (x86_64-pc-linux-gnu)"

In function:

echo $@;              #"p1" "p2" "p3" "p4" "p5"
echo ${@: 0};  #"bash" "p1" "p2" "p3" "p4" "p5"
echo ${@: 1};         #"p1" "p2" "p3" "p4" "p5"
echo ${@: 2};              #"p2" "p3" "p4" "p5"
echo ${@: 2:1};            #"p2"
echo ${@: 2:2};            #"p2" "p3"
echo ${@: -2};                       #"p4" "p5"
echo ${@: -2:1};                     #"p4"

Notice the space between ':' and '-', otherwise it means different:

${var:-word} If var is null or unset,
word is substituted for var. The value of var does not change.

${var:+word} If var is set,
word is substituted for var. The value of var does not change.

Which is described in:Unix / Linux - Shell Substitution

Getting strings recognized as variable names in R

The basic answer to the question in the title is eval(as.symbol(variable_name_as_string)) as Josh O'Brien uses. e.g.

var.name = "x"
assign(var.name, 5)
eval(as.symbol(var.name)) # outputs 5

Or more simply:

get(var.name) # 5

correct way to define class variables in Python

Neither way is necessarily correct or incorrect, they are just two different kinds of class elements:

  • Elements outside the __init__ method are static elements; they belong to the class.
  • Elements inside the __init__ method are elements of the object (self); they don't belong to the class.

You'll see it more clearly with some code:

class MyClass:
    static_elem = 123

    def __init__(self):
        self.object_elem = 456

c1 = MyClass()
c2 = MyClass()

# Initial values of both elements
>>> print c1.static_elem, c1.object_elem 
123 456
>>> print c2.static_elem, c2.object_elem
123 456

# Nothing new so far ...

# Let's try changing the static element
MyClass.static_elem = 999

>>> print c1.static_elem, c1.object_elem
999 456
>>> print c2.static_elem, c2.object_elem
999 456

# Now, let's try changing the object element
c1.object_elem = 888

>>> print c1.static_elem, c1.object_elem
999 888
>>> print c2.static_elem, c2.object_elem
999 456

As you can see, when we changed the class element, it changed for both objects. But, when we changed the object element, the other object remained unchanged.

Styling HTML email for Gmail

Gmail started basic support for style tags in the head area. Found nothing official yet but you can easily try it yourself.
It seems to ignore class and id selectors but basic element selectors work.

<!doctype html>
<html>
  <head>
    <style type="text/css">
      p{font-family:Tahoma,sans-serif;font-size:12px;margin:0}  
    </style>
  </head>
  <body>
    <p>Email content here</p>
  </body>
</html>

it will create a style tag in its own head area limited to the div containing the mail body

<style>div.m14623dcb877eef15 p{font-family:Tahoma,sans-serif;font-size:12px;margin:0}</style>

websocket closing connection automatically

Here is an example on how to configure Jetty's websocket timeout (the most likely culprit) using WebSocketServlet (in scala, sorry, but the syntax is pretty much the same).

import javax.servlet.annotation.WebServlet
import org.eclipse.jetty.websocket.servlet.{WebSocketServletFactory, WebSocketServlet}

@WebServlet(name = "WebSocket Servlet")
class WebsocketServlet extends WebSocketServlet {
  override def configure(factory: WebSocketServletFactory): Unit = {
    factory.getPolicy.setIdleTimeout(1000 * 3600)
    factory.register(classOf[ClientWebsocket])
  }
}

Why do I get permission denied when I try use "make" to install something?

On many source packages (e.g. for most GNU software), the building system may know about the DESTDIR make variable, so you can often do:

 make install DESTDIR=/tmp/myinst/
 sudo cp -va /tmp/myinst/ /

The advantage of this approach is that make install don't need to run as root, so you cannot end up with files compiled as root (or root-owned files in your build tree).

How to beautify JSON in Python?

From the command-line:

echo '{"one":1,"two":2}' | python -mjson.tool

which outputs:

{
    "one": 1, 
    "two": 2
}

Programmtically, the Python manual describes pretty-printing JSON:

>>> import json
>>> print json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4)
{
    "4": 5,
    "6": 7
}

Read XML file into XmlDocument

XmlDocument doc = new XmlDocument();
   doc.Load("MonFichierXML.xml");

    XmlNode node = doc.SelectSingleNode("Magasin");

    XmlNodeList prop = node.SelectNodes("Items");

    foreach (XmlNode item in prop)
    {
        items Temp = new items();
        Temp.AssignInfo(item);
        lstitems.Add(Temp);
    }

How can I convert spaces to tabs in Vim or Linux?

If you have GNU coreutils installed, consider %!unexpand --first-only or for 4-space tabs, consider %!unexpand -t 4 --first-only (--first-only is present just in case you were accidentally invoking unexpand with --all).

Note that this will only replace the spaces preceding the prescribed tab stops, not the spaces that follow them; you will see no visual difference in vim unless you display tabs more literally; for example, my ~/.vimrc contains set list listchars=tab:?? (I suspect this is why you thought unexpand didn't work).

Select mySQL based only on month and year

Suppose you have a database field created_at Where you take value from timestamp. You want to search by Year & Month from created_at date.

YEAR(date(created_at))=2019 AND MONTH(date(created_at))=2