Programs & Examples On #Html help

Why does JSHint throw a warning if I am using const?

If you are using Webstorm and if you don't have your own config file, then just enable EcmaScript.next in Relaxing options in in

Settings | Languages & Frameworks | JavaScript | Code Quality Tools | JSHint

See this question How-do-I-resolve-these-JSHint-ES6-errors

How to bundle vendor scripts separately and require them as needed with Webpack?

I am not sure if I fully understand your problem but since I had similar issue recently I will try to help you out.

Vendor bundle.

You should use CommonsChunkPlugin for that. in the configuration you specify the name of the chunk (e.g. vendor), and file name that will be generated (vendor.js).

new webpack.optimize.CommonsChunkPlugin("vendor", "vendor.js", Infinity),

Now important part, you have to now specify what does it mean vendor library and you do that in an entry section. One one more item to entry list with the same name as the name of the newly declared chunk (i.e. 'vendor' in this case). The value of that entry should be the list of all the modules that you want to move to vendor bundle. in your case it should look something like:

entry: {
    app: 'entry.js',
    vendor: ['jquery', 'jquery.plugin1']
}

JQuery as global

Had the same problem and solved it with ProvidePlugin. here you are not defining global object but kind of shurtcuts to modules. i.e. you can configure it like that:

new webpack.ProvidePlugin({
    $: "jquery"
})

And now you can just use $ anywhere in your code - webpack will automatically convert that to

require('jquery')

I hope it helped. you can also look at my webpack configuration file that is here

I love webpack, but I agree that the documentation is not the nicest one in the world... but hey.. people were saying same thing about Angular documentation in the begining :)


Edit:

To have entrypoint-specific vendor chunks just use CommonsChunkPlugins multiple times:

new webpack.optimize.CommonsChunkPlugin("vendor-page1", "vendor-page1.js", Infinity),
new webpack.optimize.CommonsChunkPlugin("vendor-page2", "vendor-page2.js", Infinity),

and then declare different extenral libraries for different files:

entry: {
    page1: ['entry.js'],
    page2: ['entry2.js'],
    "vendor-page1": [
        'lodash'
    ],
    "vendor-page2": [
        'jquery'
    ]
},

If some libraries are overlapping (and for most of them) between entry points then you can extract them to common file using same plugin just with different configuration. See this example.

What should be the sizeof(int) on a 64-bit machine?

Not really. for backward compatibility it is 32 bits.
If you want 64 bits you have long, size_t or int64_t

Xampp localhost/dashboard

If you want to display directory than edit htdocs/index.php file

Below code is display all directory in table

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Welcome to Nims Server</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<link href="server/style.css" rel="stylesheet" type="text/css" />
</head>
<body>
<!-- START PAGE SOURCE -->
<div id="wrap">
  <div id="top">
    <h1 id="sitename">Nims <em>Server</em> Directory list</h1>
    <div id="searchbar">
      <form action="#">
        <div id="searchfield">
          <input type="text" name="keyword" class="keyword" />
          <input class="searchbutton" type="image" src="server/images/searchgo.gif"  alt="search" />
        </div>
      </form>
    </div>
  </div>

<div class="background">
<div class="transbox">
<table width="100%" border="0" cellspacing="3" cellpadding="5" style="border:0px solid #333333;background: #F9F9F9;"> 
<tr>
<?php
//echo md5("saketbook007");

//File functuion DIR is used here.
$d = dir($_SERVER['DOCUMENT_ROOT']); 
$i=-1;
//Loop start with read function
while ($entry = $d->read()) {
if($entry == "." || $entry ==".."){
}else{
?>
<td  class="site" width="33%"><a href="<?php echo $entry;?>" ><?php echo ucfirst($entry); ?></a></td>  
<?php 
}
if($i%3 == 0){
echo "</tr><tr>";
}
$i++;
}?>
</tr> 
</table>

<?php $d->close();
?> 

</div>
</div>
</div>
   </div></div></body>
</html>

Style:

@import url("fontface.css");
* {
    padding:0;
    margin:0;
}
.clear {
    clear:both;
}

body {
    background:url(images/bg.jpg) repeat;
    font-family:"Palatino Linotype", "Book Antiqua", Palatino, serif;
    color:#212713;
}
#wrap {
    width:1300px;
    margin:auto;
}

#sitename {
    font: normal 46px chunk;
    color:#1b2502;
    text-shadow:#5d7a17 1px 1px 1px;
    display:block;
    padding:45px 0 0 0;
    width:60%;
    float:left;
}
#searchbar {
    width:39%;
    float:right;
}
#sitename em {
    font-family:"Palatino Linotype", "Book Antiqua", Palatino, serif;
}
#top {
    height:145px;
}
img {

    width:90%;
    height:250px;
    padding:10px;
    border:1px solid #000;
    margin:0 0 0 50px;
}


.post h2 a {
    color:#656f42;
    text-decoration:none;
}
#searchbar {
    padding:55px 0 0 0;
}
#searchfield {
    background:url(images/searchbar.gif) no-repeat;
    width:239px;
    height:35px;
    float:right;
}
#searchfield .keyword {
    width:170px;
    background:transparent;
    border:none;
    padding:8px 0 0 10px;
    color:#fff;
    display:block;
    float:left;
}
#searchfield .searchbutton {
    display:block;
    float:left;
    margin:7px 0 0 5px;
}

div.background
{
  background:url(h.jpg) repeat-x;
  border: 2px solid black;

  width:99%;
}
div.transbox
{
  margin: 15px;
  background-color: #ffffff;

  border: 1px solid black;
  opacity:0.8;
  filter:alpha(opacity=60); /* For IE8 and earlier */
  height:500px;
}

.site{

border:1px solid #CCC; 
}

.site a{text-decoration:none;font-weight:bold; color:#000; line-height:2}
.site:hover{background:#000; border:1px solid #03C;}
.site:hover a{color:#FFF}

Output : enter image description here

How to set the color of "placeholder" text?

For Firefox use:

 input:-moz-placeholder { color: #aaa; }
 textarea:-moz-placeholder { color: #aaa;}

For all other browsers (Chrome, IE, Safari), just use:

 .placeholder { color: #aaa; }

How to create standard Borderless buttons (like in the design guideline mentioned)?

This is how you create a borderless (flat) button programmatically without using XML

ContextThemeWrapper myContext = new ContextThemeWrapper(this.getActivity(), 
   R.style.Widget_AppCompat_Button_Borderless_Colored);

Button myButton = new Button(myContext, null, 
   R.style.Widget_AppCompat_Button_Borderless_Colored);

Import regular CSS file in SCSS file?

Good news everyone, Chris Eppstein created a compass plugin with inline css import functionality:

https://github.com/chriseppstein/sass-css-importer

Now, importing a CSS file is as easy as:

@import "CSS:library/some_css_file"

Adding items to a JComboBox

Method call setSelectedIndex("item_value"); doesn't work because setSelectedIndex use sequential index.

null check in jsf expression language

Use empty (it checks both nullness and emptiness) and group the nested ternary expression by parentheses (EL is in certain implementations/versions namely somewhat problematic with nested ternary expressions). Thus, so:

styleClass="#{empty obj.validationErrorMap ? ' ' :  
 (obj.validationErrorMap.contains('key') ? 'highlight_field' : 'highlight_row')}"

If still in vain (I would then check JBoss EL configs), use the "normal" EL approach:

styleClass="#{empty obj.validationErrorMap ? ' ' :  
 (obj.validationErrorMap['key'] ne null ? 'highlight_field' : 'highlight_row')}"

Update: as per the comments, the Map turns out to actually be a List (please work on your naming conventions). To check if a List contains an item the "normal" EL way, use JSTL fn:contains (although not explicitly documented, it works for List as well).

styleClass="#{empty obj.validationErrorMap ? ' ' :  
 (fn:contains(obj.validationErrorMap, 'key') ? 'highlight_field' : 'highlight_row')}"

How to get absolute value from double - c-language

  //use fabs()
  double sum_primary_diagonal=0;
  double sum_secondary_diagonal=0;
  double difference = fabs(sum_primary_diagonal - sum_secondary_diagonal);

Apply a function to every row of a matrix or a data frame

Another approach if you want to use a varying portion of the dataset instead of a single value is to use rollapply(data, width, FUN, ...). Using a vector of widths allows you to apply a function on a varying window of the dataset. I've used this to build an adaptive filtering routine, though it isn't very efficient.

How to map an array of objects in React

you must put object in your JSX, It`s easy way to do this just see my simple code here:

const link = [
  {
   name: "Cold Drink",
   link: "/coldDrink"
  },
  {
   name: "Hot Drink",
   link: "/HotDrink"
  },

{ name: "chease Cake", link: "/CheaseCake" } ]; and you must map this array in your code with simple object see this code :

const links = (this.props.link);
{links.map((item, i) => (
 <li key={i}>
   <Link to={item.link}>{item.name}</Link>
 </li>
 ))}

I hope this answer will be helpful for you ...:)

Read specific columns with pandas or other python module

According to the latest pandas documentation you can read a csv file selecting only the columns which you want to read.

import pandas as pd

df = pd.read_csv('some_data.csv', usecols = ['col1','col2'], low_memory = True)

Here we use usecols which reads only selected columns in a dataframe.

We are using low_memory so that we Internally process the file in chunks.

Email address validation using ASP.NET MVC data type attributes

I use MVC 3. An example of email address property in one of my classes is:

[Display(Name = "Email address")]
[Required(ErrorMessage = "The email address is required")]
[Email(ErrorMessage = "The email address is not valid")]
public string Email { get; set; }

Remove the Required if the input is optional. No need for regular expressions although I have one which covers all of the options within an email address up to RFC 2822 level (it's very long).

TCPDF not render all CSS properties

TCPDF 6.2.11 (2015-08-02)

Some things won't work when included within <style> tags, however they will if added in a style="" attribute in the HTML tag. E.g. table padding – this doesn't work:

table {
    padding: 5px;
}

This does:

<table style="padding: 5px;">

Passing an array as a function parameter in JavaScript

Function arguments may also be Arrays:

_x000D_
_x000D_
function foo([a,b,c], d){
  console.log(a,b,c,d);
}

foo([1,2,3], 4)
_x000D_
_x000D_
_x000D_

of-course one can also use spread:

_x000D_
_x000D_
function foo(a, b, c, d){
  console.log(a, b, c, d);
}

foo(...[1, 2, 3], 4)
_x000D_
_x000D_
_x000D_

Swift Open Link in Safari

UPDATED for Swift 4: (credit to Marco Weber)

if let requestUrl = NSURL(string: "http://www.iSecurityPlus.com") {
     UIApplication.shared.openURL(requestUrl as URL) 
}

OR go with more of swift style using guard:

guard let requestUrl = NSURL(string: "http://www.iSecurityPlus.com") else {
    return
}

UIApplication.shared.openURL(requestUrl as URL) 

Swift 3:

You can check NSURL as optional implicitly by:

if let requestUrl = NSURL(string: "http://www.iSecurityPlus.com") {
     UIApplication.sharedApplication().openURL(requestUrl)
}

SQL Server stored procedure parameters

Why would you pass a parameter to a stored procedure that doesn't use it?

It sounds to me like you might be better of building dynamic SQL statements and then executing them. What you are trying to do with the SP won't work, and even if you could change what you are doing in such a way to accommodate varying numbers of parameters, you would then essentially be using dynamically generated SQL you are defeating the purpose of having/using a SP in the first place. SP's have a role, but there are not the solution in all cases.

How to use zIndex in react-native

I finally solved this by creating a second object that imitates B.

My schema now looks like this:

enter image description here

I now have B1 (within parent of A) and B2 outside of it.

B1 and B2 are right next to one another, so to the naked eye it looks as if it's just 1 object.

Why doesn't C++ have a garbage collector?

To add to the debate here.

There are known issues with garbage collection, and understanding them helps understanding why there is none in C++.

1. Performance ?

The first complaint is often about performance, but most people don't really realize what they are talking about. As illustrated by Martin Beckett the problem may not be performance per se, but the predictability of performance.

There are currently 2 families of GC that are widely deployed:

  • Mark-And-Sweep kind
  • Reference-Counting kind

The Mark And Sweep is faster (less impact on overall performance) but it suffers from a "freeze the world" syndrome: i.e. when the GC kicks in, everything else is stopped until the GC has made its cleanup. If you wish to build a server that answers in a few milliseconds... some transactions will not live up to your expectations :)

The problem of Reference Counting is different: reference-counting adds overhead, especially in Multi-Threading environments because you need to have an atomic count. Furthermore there is the problem of reference cycles so you need a clever algorithm to detect those cycles and eliminate them (generally implement by a "freeze the world" too, though less frequent). In general, as of today, this kind (even though normally more responsive or rather, freezing less often) is slower than the Mark And Sweep.

I have seen a paper by Eiffel implementers that were trying to implement a Reference Counting Garbage Collector that would have a similar global performance to Mark And Sweep without the "Freeze The World" aspect. It required a separate thread for the GC (typical). The algorithm was a bit frightening (at the end) but the paper made a good job of introducing the concepts one at a time and showing the evolution of the algorithm from the "simple" version to the full-fledged one. Recommended reading if only I could put my hands back on the PDF file...

2. Resources Acquisition Is Initialization (RAII)

It's a common idiom in C++ that you will wrap the ownership of resources within an object to ensure that they are properly released. It's mostly used for memory since we don't have garbage collection, but it's also useful nonetheless for many other situations:

  • locks (multi-thread, file handle, ...)
  • connections (to a database, another server, ...)

The idea is to properly control the lifetime of the object:

  • it should be alive as long as you need it
  • it should be killed when you're done with it

The problem of GC is that if it helps with the former and ultimately guarantees that later... this "ultimate" may not be sufficient. If you release a lock, you'd really like that it be released now, so that it does not block any further calls!

Languages with GC have two work arounds:

  • don't use GC when stack allocation is sufficient: it's normally for performance issues, but in our case it really helps since the scope defines the lifetime
  • using construct... but it's explicit (weak) RAII while in C++ RAII is implicit so that the user CANNOT unwittingly make the error (by omitting the using keyword)

3. Smart Pointers

Smart pointers often appear as a silver bullet to handle memory in C++. Often times I have heard: we don't need GC after all, since we have smart pointers.

One could not be more wrong.

Smart pointers do help: auto_ptr and unique_ptr use RAII concepts, extremely useful indeed. They are so simple that you can write them by yourself quite easily.

When one need to share ownership however it gets more difficult: you might share among multiple threads and there are a few subtle issues with the handling of the count. Therefore, one naturally goes toward shared_ptr.

It's great, that's what Boost for after all, but it's not a silver bullet. In fact, the main issue with shared_ptr is that it emulates a GC implemented by Reference Counting but you need to implement the cycle detection all by yourself... Urg

Of course there is this weak_ptr thingy, but I have unfortunately already seen memory leaks despite the use of shared_ptr because of those cycles... and when you are in a Multi Threaded environment, it's extremely difficult to detect!

4. What's the solution ?

There is no silver bullet, but as always, it's definitely feasible. In the absence of GC one need to be clear on ownership:

  • prefer having a single owner at one given time, if possible
  • if not, make sure that your class diagram does not have any cycle pertaining to ownership and break them with subtle application of weak_ptr

So indeed, it would be great to have a GC... however it's no trivial issue. And in the mean time, we just need to roll up our sleeves.

Maven: add a dependency to a jar by relative path

You can use eclipse to generate a runnable Jar : Export/Runable Jar file

Eclipse DDMS error "Can't bind to local 8600 for debugger"

Worked for me, based on this answer

In Eclipse go to

Window->Preference->Android->DDMS

Then tick "Use ADBHOST" as "127.0.0.1".

Then just restart eclipse

What is the purpose of a plus symbol before a variable?

The + operator returns the numeric representation of the object. So in your particular case, it would appear to be predicating the if on whether or not d is a non-zero number.

Reference here. And, as pointed out in comments, here.

Convert integer to binary in C#

Another alternative but also inline solution using Enumerable and LINQ is:

int number = 25;

string binary = Enumerable.Range(0, (int) Math.Log(number, 2) + 1).Aggregate(string.Empty, (collected, bitshifts) => ((number >> bitshifts) & 1 )+ collected);

What is the difference between varchar and varchar2 in Oracle?

As for now, they are synonyms.

VARCHAR is reserved by Oracle to support distinction between NULL and empty string in future, as ANSI standard prescribes.

VARCHAR2 does not distinguish between a NULL and empty string, and never will.

If you rely on empty string and NULL being the same thing, you should use VARCHAR2.

Core dumped, but core file is not in the current directory?

With the launch of systemd, there's another scenario aswell. By default systemd will store core dumps in its journal, being accessible with the systemd-coredumpctl command. Defined in the core_pattern-file:

$ cat /proc/sys/kernel/core_pattern 
|/usr/lib/systemd/systemd-coredump %p %u %g %s %t %e

This behaviour can be disabled with a simple "hack":

$ ln -s /dev/null /etc/sysctl.d/50-coredump.conf
$ sysctl -w kernel.core_pattern=core      # or just reboot

As always, the size of core dumps has to be equal or higher than the size of the core that is being dumped, as done by for example ulimit -c unlimited.

origin 'http://localhost:4200' has been blocked by CORS policy in Angular7

For temporary testing during development we can disable it by opening chrome with disabled web security like this.

Open command line terminal and go to folder where chrome is installed i.e. C:\Program Files (x86)\Google\Chrome\Application

Enter this command:

chrome.exe --user-data-dir="C:/Chrome dev session" --disable-web-security

A new browser window will open with disabled web security. Use it only for testing your app.

Error: unable to verify the first certificate in nodejs

I met very rare case, but hopely it could help to someone: made a proxy service, which proxied requests to another service. And every request's error was "unable to verify the first certificate" even when i added all expected certificates.

The reason was pretty simple - i accidently re-sent also the "host" header. Just make sure you don't send "host" header explicitly.

calling parent class method from child class object in java

Say the hierarchy is C->B->A with A being the base class.

I think there's more to fixing this than renaming a method. That will work but is that a fix?

One way is to refactor all the functionality common to B and C into D, and let B and C inherit from D: (B,C)->D->A Now the method in B that was hiding A's implementation from C is specific to B and stays there. This allows C to invoke the method in A without any hokery.

Docker container will automatically stop after "docker run -d"

Background

A Docker container runs a process (the "command" or "entrypoint") that keeps it alive. The container will continue to run as long as the command continues to run.

In your case, the command (/bin/bash, by default, on centos:latest) is exiting immediately (as bash does when it's not connected to a terminal and has nothing to run).

Normally, when you run a container in daemon mode (with -d), the container is running some sort of daemon process (like httpd). In this case, as long as the httpd daemon is running, the container will remain alive.

What you appear to be trying to do is to keep the container alive without a daemon process running inside the container. This is somewhat strange (because the container isn't doing anything useful until you interact with it, perhaps with docker exec), but there are certain cases where it might make sense to do something like this.

(Did you mean to get to a bash prompt inside the container? That's easy! docker run -it centos:latest)

Solution

A simple way to keep a container alive in daemon mode indefinitely is to run sleep infinity as the container's command. This does not rely doing strange things like allocating a TTY in daemon mode. Although it does rely on doing strange things like using sleep as your primary command.

$ docker run -d centos:latest sleep infinity
$ docker ps
CONTAINER ID  IMAGE         COMMAND          CREATED       STATUS       PORTS NAMES
d651c7a9e0ad  centos:latest "sleep infinity" 2 seconds ago Up 2 seconds       nervous_visvesvaraya

Alternative Solution

As indicated by cjsimon, the -t option allocates a "pseudo-tty". This tricks bash into continuing to run indefinitely because it thinks it is connected to an interactive TTY (even though you have no way to interact with that particular TTY if you don't pass -i). Anyway, this should do the trick too:

$ docker run -t -d centos:latest

Not 100% sure whether -t will produce other weird interactions; maybe leave a comment below if it does.

Inline labels in Matplotlib

@Jan Kuiken's answer is certainly well-thought and thorough, but there are some caveats:

  • it does not work in all cases
  • it requires a fair amount of extra code
  • it may vary considerably from one plot to the next

A much simpler approach is to annotate the last point of each plot. The point can also be circled, for emphasis. This can be accomplished with one extra line:

from matplotlib import pyplot as plt

for i, (x, y) in enumerate(samples):
    plt.plot(x, y)
    plt.text(x[-1], y[-1], 'sample {i}'.format(i=i))

A variant would be to use ax.annotate.

How to urlencode data for curl command?

Here is my version for busybox ash shell for an embedded system, I originally adopted Orwellophile's variant:

urlencode()
{
    local S="${1}"
    local encoded=""
    local ch
    local o
    for i in $(seq 0 $((${#S} - 1)) )
    do
        ch=${S:$i:1}
        case "${ch}" in
            [-_.~a-zA-Z0-9]) 
                o="${ch}"
                ;;
            *) 
                o=$(printf '%%%02x' "'$ch")                
                ;;
        esac
        encoded="${encoded}${o}"
    done
    echo ${encoded}
}

urldecode() 
{
    # urldecode <string>
    local url_encoded="${1//+/ }"
    printf '%b' "${url_encoded//%/\\x}"
}

How to include Javascript file in Asp.Net page

I assume that you are using MasterPage so within your master page you should have

<head runat="server">
    <asp:ContentPlaceHolder ID="head" runat="server">
    </asp:ContentPlaceHolder>
</head>

And within any of your pages based on that MasterPage add this

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
    <script src="js/yourscript.js" type="text/javascript"></script>
</asp:Content>

How to declare Return Types for Functions in TypeScript

You are correct - here is a fully working example - you'll see that var result is implicitly a string because the return type is specified on the greet() function. Change the type to number and you'll get warnings.

class Greeter {
    greeting: string;
    constructor (message: string) {
        this.greeting = message;
    }
    greet() : string {
        return "Hello, " + this.greeting;
    }
} 

var greeter = new Greeter("Hi");
var result = greeter.greet();

Here is the number example - you'll see red squiggles in the playground editor if you try this:

greet() : number {
    return "Hello, " + this.greeting;
}

ASP.NET Background image

resize your background image in an image editor to the size you want related to your login box, which should help page loading and preserve image quality...

hard-size your DIV relative to your image

position your asp:login control where needed...

How to check if any Checkbox is checked in Angular

I've a sample for multiple data with their subnode 3 list , each list has attribute and child attribute:

var list1 = {
    name: "Role A",
    name_selected: false,
    subs: [{
        sub: "Read",
        id: 1,
        selected: false
    }, {
        sub: "Write",
        id: 2,
        selected: false
    }, {
        sub: "Update",
        id: 3,
        selected: false
    }],
};
var list2 = {
    name: "Role B",
    name_selected: false,
    subs: [{
        sub: "Read",
        id: 1,
        selected: false
    }, {
        sub: "Write",
        id: 2,
        selected: false
    }],
};
var list3 = {
    name: "Role B",
    name_selected: false,
    subs: [{
        sub: "Read",
        id: 1,
        selected: false
    }, {
        sub: "Update",
        id: 3,
        selected: false
    }],
};

Add these to Array :

newArr.push(list1);
newArr.push(list2);
newArr.push(list3);
$scope.itemDisplayed = newArr;

Show them in html:

<li ng-repeat="item in itemDisplayed" class="ng-scope has-pretty-child">
    <div>
        <ul>
            <input type="checkbox" class="checkall" ng-model="item.name_selected" ng-click="toggleAll(item)" />
            <span>{{item.name}}</span>
            <div>
                <li ng-repeat="sub in item.subs" class="ng-scope has-pretty-child">
                    <input type="checkbox" kv-pretty-check="" ng-model="sub.selected" ng-change="optionToggled(item,item.subs)"><span>{{sub.sub}}</span>
                </li>
            </div>
        </ul>
    </div>
</li>

And here is the solution to check them:

$scope.toggleAll = function(item) {
    var toogleStatus = !item.name_selected;
    console.log(toogleStatus);
    angular.forEach(item, function() {
        angular.forEach(item.subs, function(sub) {
            sub.selected = toogleStatus;
        });
    });
};

$scope.optionToggled = function(item, subs) {
    item.name_selected = subs.every(function(itm) {
        return itm.selected;
    })
}

jsfiddle demo

How can I solve ORA-00911: invalid character error?

I had the same problem and it was due to the end of line. I had copied from another document. I put everythng on the same line, then split them again and it worked.

How to rename a file using Python

As of Python 3.4 one can use the pathlib module to solve this.

If you happen to be on an older version, you can use the backported version found here

Let's assume you are not in the root path (just to add a bit of difficulty to it) you want to rename, and have to provide a full path, we can look at this:

some_path = 'a/b/c/the_file.extension'

So, you can take your path and create a Path object out of it:

from pathlib import Path
p = Path(some_path)

Just to provide some information around this object we have now, we can extract things out of it. For example, if for whatever reason we want to rename the file by modifying the filename from the_file to the_file_1, then we can get the filename part:

name_without_extension = p.stem

And still hold the extension in hand as well:

ext = p.suffix

We can perform our modification with a simple string manipulation:

Python 3.6 and greater make use of f-strings!

new_file_name = f"{name_without_extension}_1"

Otherwise:

new_file_name = "{}_{}".format(name_without_extension, 1)

And now we can perform our rename by calling the rename method on the path object we created and appending the ext to complete the proper rename structure we want:

p.rename(Path(p.parent, new_file_name + ext))

More shortly to showcase its simplicity:

Python 3.6+:

from pathlib import Path
p = Path(some_path)
p.rename(Path(p.parent, f"{p.stem}_1_{p.suffix}"))

Versions less than Python 3.6 use the string format method instead:

from pathlib import Path
p = Path(some_path)
p.rename(Path(p.parent, "{}_{}_{}".format(p.stem, 1, p.suffix))

Closing Excel Application using VBA

Sub button2_click()
'
' Button2_Click Macro
'
' Keyboard Shortcut: Ctrl+Shift+Q
'
    ActiveSheet.Shapes("Button 2").Select
    Selection.Characters.Text = "Logout"
    ActiveSheet.Shapes("Button 2").Select
    Selection.OnAction = "Button2_Click"
    ActiveWorkbook.Saved = True
    ActiveWorkbook.Save
    Application.Quit
End Sub

AccessDenied for ListObjects for S3 bucket when permissions are s3:*

To allow permissions in s3 bucket go to the permissions tab in s3 bucket and in bucket policy change the action to this which will allow all actions to be performed:

"Action":"*"

'list' object has no attribute 'shape'

import numpy
X = numpy.array(the_big_nested_list_you_had)

It's still not going to do what you want; you have more bugs, like trying to unpack a 3-dimensional shape into two target variables in test.

Single controller with multiple GET methods in ASP.NET Web API

This is the best way I have found to support extra GET methods and support the normal REST methods as well. Add the following routes to your WebApiConfig:

routes.MapHttpRoute("DefaultApiWithId", "Api/{controller}/{id}", new { id = RouteParameter.Optional }, new { id = @"\d+" });
routes.MapHttpRoute("DefaultApiWithAction", "Api/{controller}/{action}");
routes.MapHttpRoute("DefaultApiGet", "Api/{controller}", new { action = "Get" }, new { httpMethod = new HttpMethodConstraint(HttpMethod.Get) });
routes.MapHttpRoute("DefaultApiPost", "Api/{controller}", new {action = "Post"}, new {httpMethod = new HttpMethodConstraint(HttpMethod.Post)});

I verified this solution with the test class below. I was able to successfully hit each method in my controller below:

public class TestController : ApiController
{
    public string Get()
    {
        return string.Empty;
    }

    public string Get(int id)
    {
        return string.Empty;
    }

    public string GetAll()
    {
        return string.Empty;
    }

    public void Post([FromBody]string value)
    {
    }

    public void Put(int id, [FromBody]string value)
    {
    }

    public void Delete(int id)
    {
    }
}

I verified that it supports the following requests:

GET /Test
GET /Test/1
GET /Test/GetAll
POST /Test
PUT /Test/1
DELETE /Test/1

Note That if your extra GET actions do not begin with 'Get' you may want to add an HttpGet attribute to the method.

Adjust list style image position?

Hide the default bullet image and use background-image as you have much more control like:

_x000D_
_x000D_
li {_x000D_
    background-image: url(https://material.io/tools/icons/static/icons/baseline-add-24px.svg);_x000D_
    background-repeat: no-repeat;_x000D_
    background-position: left 50%;_x000D_
    padding-left: 2em;_x000D_
}_x000D_
_x000D_
ul {_x000D_
    list-style: none;_x000D_
}
_x000D_
<ul>_x000D_
<li>foo</li>_x000D_
<li>bar</li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

SDK Manager.exe doesn't work

I had the same problem.

when i run \tools\android.bat, i got the exception: Exception in thread main

 java.lang.NoClassDefFoundError: com/android/sdkmanager/Main

My resolved method:

  1. edit \tools\android.bat
  2. find "%jar_path%;%swt_path%\swt.jar"
  3. modify to "%tools_dir%\%jar_path%;%tools_dir%\%swt_path%\swt.jar"
  4. save, and run SDK Manager.exe again

How can I define an interface for an array of objects with Typescript?

Easy option with no tslint errors ...

export interface MyItem {
    id: number
    name: string
}

export type MyItemList = [MyItem]

Add space between cells (td) using css

If you want separate values for sides and top-bottom.

<table style="border-spacing: 5px 10px;">

Interface defining a constructor signature?

I use the following pattern to make it bulletproof.

  • A developer who derives his class from the base can't accidentally create a public accessible constructor
  • The final class developer are forced to go through the common create method
  • Everything is type-safe, no castings are required
  • It's 100% flexible and can be reused everywhere, where you can define your own base class.
  • Try it out you can't break it without making modifications to the base classes (except if you define an obsolete flag without error flag set to true, but even then you end up with a warning)

        public abstract class Base<TSelf, TParameter>
        where TSelf : Base<TSelf, TParameter>, new()
    {
        protected const string FactoryMessage = "Use YourClass.Create(...) instead";
        public static TSelf Create(TParameter parameter)
        {
            var me = new TSelf();
            me.Initialize(parameter);
    
            return me;
        }
    
        [Obsolete(FactoryMessage, true)]
        protected Base()
        {
        }
    
    
    
        protected virtual void Initialize(TParameter parameter)
        {
    
        }
    }
    
    public abstract class BaseWithConfig<TSelf, TConfig>: Base<TSelf, TConfig>
        where TSelf : BaseWithConfig<TSelf, TConfig>, new()
    {
        public TConfig Config { get; private set; }
    
        [Obsolete(FactoryMessage, true)]
        protected BaseWithConfig()
        {
        }
        protected override void Initialize(TConfig parameter)
        {
            this.Config = parameter;
        }
    }
    
    public class MyService : BaseWithConfig<MyService, (string UserName, string Password)>
    {
        [Obsolete(FactoryMessage, true)]
        public MyService()
        {
        }
    }
    
    public class Person : Base<Person, (string FirstName, string LastName)>
    {
        [Obsolete(FactoryMessage,true)]
        public Person()
        {
        }
    
        protected override void Initialize((string FirstName, string LastName) parameter)
        {
            this.FirstName = parameter.FirstName;
            this.LastName = parameter.LastName;
        }
    
        public string LastName { get; private set; }
    
        public string FirstName { get; private set; }
    }
    
    
    
    [Test]
    public void FactoryTest()
    {
        var notInitilaizedPerson = new Person(); // doesn't compile because of the obsolete attribute.
        Person max = Person.Create(("Max", "Mustermann"));
        Assert.AreEqual("Max",max.FirstName);
    
        var service = MyService.Create(("MyUser", "MyPassword"));
        Assert.AreEqual("MyUser", service.Config.UserName);
    }
    

EDIT: And here is an example based on your drawing example that even enforces interface abstraction

        public abstract class BaseWithAbstraction<TSelf, TInterface, TParameter>
        where TSelf : BaseWithAbstraction<TSelf, TInterface, TParameter>, TInterface, new()
    {
        [Obsolete(FactoryMessage, true)]
        protected BaseWithAbstraction()
        {
        }

        protected const string FactoryMessage = "Use YourClass.Create(...) instead";
        public static TInterface Create(TParameter parameter)
        {
            var me = new TSelf();
            me.Initialize(parameter);

            return me;
        }

        protected virtual void Initialize(TParameter parameter)
        {

        }
    }



    public abstract class BaseWithParameter<TSelf, TInterface, TParameter> : BaseWithAbstraction<TSelf, TInterface, TParameter>
        where TSelf : BaseWithParameter<TSelf, TInterface, TParameter>, TInterface, new()
    {
        protected TParameter Parameter { get; private set; }

        [Obsolete(FactoryMessage, true)]
        protected BaseWithParameter()
        {
        }
        protected sealed override void Initialize(TParameter parameter)
        {
            this.Parameter = parameter;
            this.OnAfterInitialize(parameter);
        }

        protected virtual void OnAfterInitialize(TParameter parameter)
        {
        }
    }


    public class GraphicsDeviceManager
    {

    }
    public interface IDrawable
    {
        void Update();
        void Draw();
    }

    internal abstract class Drawable<TSelf> : BaseWithParameter<TSelf, IDrawable, GraphicsDeviceManager>, IDrawable 
        where TSelf : Drawable<TSelf>, IDrawable, new()
    {
        [Obsolete(FactoryMessage, true)]
        protected Drawable()
        {
        }

        public abstract void Update();
        public abstract void Draw();
    }

    internal class Rectangle : Drawable<Rectangle>
    {
        [Obsolete(FactoryMessage, true)]
        public Rectangle()
        {
        }

        public override void Update()
        {
            GraphicsDeviceManager manager = this.Parameter;
            // TODo  manager
        }

        public override void Draw()
        {
            GraphicsDeviceManager manager = this.Parameter;
            // TODo  manager
        }
    }
    internal class Circle : Drawable<Circle>
    {
        [Obsolete(FactoryMessage, true)]
        public Circle()
        {
        }

        public override void Update()
        {
            GraphicsDeviceManager manager = this.Parameter;
            // TODo  manager
        }

        public override void Draw()
        {
            GraphicsDeviceManager manager = this.Parameter;
            // TODo  manager
        }
    }


    [Test]
    public void FactoryTest()
    {
        // doesn't compile because interface abstraction is enforced.
        Rectangle rectangle = Rectangle.Create(new GraphicsDeviceManager());

        // you get only the IDrawable returned.
        IDrawable service = Circle.Create(new GraphicsDeviceManager());
    }

C# Set collection?

If you're using .NET 3.5, you can use HashSet<T>. It's true that .NET doesn't cater for sets as well as Java does though.

The Wintellect PowerCollections may help too.

How to select a specific node with LINQ-to-XML

I'd use something like:

dim customer = (from c in xmldoc...<Customer> 
                where c.<ID>.Value=22 
                select c).SingleOrDefault 

Edit:

missed the c# tag, sorry......the example is in VB.NET

Adding POST parameters before submit

Previous answer can be shortened and be more readable.

$('#commentForm').submit(function () {
    $(this).append($.map(params, function (param) {
        return   $('<input>', {
            type: 'hidden',
            name: param.name,
            value: param.value
        })
    }))
});

configure: error: C compiler cannot create executables

First get the gcc path using

Command: which gcc

Output: /usr/bin/gcc

I had the same issue, Please set the gcc path in below command and install

CC=/usr/bin/gcc rvm install 1.9.3

Later if you get "Ruby was built without documentation" run below command

rvm docs generate-ri

undefined reference to 'std::cout'

Assuming code.cpp is the source code, the following will not throw errors:

make code
./code

Here the first command compiles the code and creates an executable with the same name, and the second command runs it. There is no need to specify g++ keyword in this case.

Select multiple columns using Entity Framework

You can select to an anonymous type, for example

var dataset2 = 
    (from recordset in entities.processlists 
    where recordset.ProcessName == processname 
    select new
    {
        serverName = recordset.ServerName,
        processId = recordset.ProcessID, 
        username = recordset.Username
    }).ToList();

Or you can create a new class that will represent your selection, for example

public class MyDataSet
{
    public string ServerName { get; set; }
    public string ProcessId { get; set; }
    public string Username { get; set; }
}

then you can for example do the following

 var dataset2 = 
    (from recordset in entities.processlists 
    where recordset.ProcessName == processname 
    select new MyDataSet
    {
        ServerName = recordset.ServerName,
        ProcessId = recordset.ProcessID, 
        Username = recordset.Username
    }).ToList();

How to allow CORS in react.js?

It is better to add CORS enabling code on Server Side. To enable CORS in NodeJS and ExpressJs based application following code should be included-

var app = express();

app.use(function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
  next();
});

C++: Where to initialize variables in constructor

Although it doesn't apply to this specific example, Option 1 allows you to initialize member variables of reference type (or const type, as pointed out below). Option 2 doesn't. In general, Option 1 is the more powerful approach.

What causes an HTTP 405 "invalid method (HTTP verb)" error when POSTing a form to PHP on IIS?

It sounds like the server is having trouble handling POST requests (get and post are verbs). I don't know, how or why someone would configure a server to ignore post requests, but the only solution would be to fix the server, or change your app to use get requests.

How to set Oracle's Java as the default Java in Ubuntu?

If you want to use specific version of Java when multiple JDKs are installed, just setting JAVA_HOME may not work.

You need to use sudo update-alternatives --config java to set default Java.

Refer to https://askubuntu.com/questions/121654/how-to-set-default-java-version.

404 Not Found The requested URL was not found on this server

If your .htaccess file is ok and the problem persist try to make the AllowOverride directive enabled in your httpd.conf. If the AllowOverride directive is set to None in your Apache httpd.config file, then .htaccess files are completely ignored. Example of enabled AllowOverride directive in httpd.config:

 <Directory />
    Options FollowSymLinks
    **AllowOverride All**
 </Directory>

Therefor restart your server.

The target ... overrides the `OTHER_LDFLAGS` build setting defined in `Pods/Pods.xcconfig

In your project, find Target -> Build Settings -> Other Linker Flags, select Other Linker Flags, press delete(Mac Keyboard)/Backspace(Normal keyboard) to recover the setting. It works for me.

Example:

Before enter image description here

After enter image description here

Measuring function execution time in R

The package "tictoc" gives you a very simple way of measuring execution time. The documentation is in: https://cran.fhcrc.org/web/packages/tictoc/tictoc.pdf.

install.packages("tictoc")
require(tictoc)
tic()
rnorm(1000,0,1)
toc()

To save the elapsed time into a variable you can do:

install.packages("tictoc")
require(tictoc)
tic()
rnorm(1000,0,1)
exectime <- toc()
exectime <- exectime$toc - exectime$tic

How do I get hour and minutes from NSDate?

With iOS 8, Apple introduced a helper method to retrieve the hour, minute, second and nanosecond from an NSDate object.

Objective-C

NSDate *date = [NSDate currentDate];
NSInteger hour = 0;
NSInteger minute = 0;
NSCalendar *currentCalendar = [NSCalendar currentCalendar];
[currentCalendar getHour:&hour minute:&minute second:NULL nanosecond:NULL fromDate:date];
NSLog(@"the hour is %ld and minute is %ld", (long)hour, (long)minute);

Swift

let date = NSDate()
var hour = 0
var minute = 0
let calendar = NSCalendar.currentCalendar()
if #available(iOS 8.0, *) {
    calendar.getHour(&hour, minute: &minute, second: nil, nanosecond: nil, fromDate: date)
    print("the hour is \(hour) and minute is \(minute)")
}

SQL ORDER BY multiple columns

The results are ordered by the first column, then the second, and so on for as many columns as the ORDER BY clause includes. If you want any results sorted in descending order, your ORDER BY clause must use the DESC keyword directly after the name or the number of the relevant column.

Check out this Example

SELECT first_name, last_name, hire_date, salary 
FROM employee 
ORDER BY hire_date DESC,last_name ASC;

It will order in succession. Order the Hire_Date first, then LAST_NAME it by Hire_Date .

Connect Android to WiFi Enterprise network EAP(PEAP)

Thanks for enlightening us Cypawer.

I also tried this app https://play.google.com/store/apps/details?id=com.oneguyinabasement.leapwifi

and it worked flawlessly.

Leap Wifi Connector

How do I update a Linq to SQL dbml file?

There are three ways to keep the model in sync.

  1. Delete the modified tables from the designer, and drag them back onto the designer surface from the Database Explorer. I have found that, for this to work reliably, you have to:

    a. Refresh the database schema in the Database Explorer (right-click, refresh)
    b. Save the designer after deleting the tables
    c. Save again after dragging the tables back.

    Note though that if you have modified any properties (for instance, turning off the child property of an association), this will obviously lose those modifications — you'll have to make them again.

  2. Use SQLMetal to regenerate the schema from your database. I have seen a number of blog posts that show how to script this.

  3. Make changes directly in the Properties pane of the DBML. This works for simple changes, like allowing nulls on a field.

The DBML designer is not installed by default in Visual Studio 2015, 2017 or 2019. You will have to close VS, start the VS installer and modify your installation. The LINQ to SQL tools is the feature you must install. For VS 2017/2019, you can find it under Individual Components > Code Tools.

How can I issue a single command from the command line through sql plus?

This is how I solved the problem:

<target name="executeSQLScript">
    <exec executable="sqlplus" failonerror="true" errorproperty="exit.status">
        <arg value="${dbUser}/${dbPass}@<DBHOST>:<DBPORT>/<SID>"/>
        <arg value="@${basedir}/db/scripttoexecute.sql"/>
    </exec>
</target>

How do I select an element in jQuery by using a variable for the ID?

I don't know much about jQuery, but try this:

row_id = "#5";
row = $("body").find(row_id);

Edit: Of course, if the variable is a number, you have to add "#" to the front:

row_id = 5
row = $("body").find("#"+row_id);

When to use Comparable and Comparator

I would say:

  • if the comparison is intuitive, then by all means implement Comparable
  • if it is unclear wether your comparison is intuitive, use a Comparator as it's more explicit and thus more clear for the poor soul who has to maintain the code
  • if there is more than one intuitive comparison possible I'd prefer a Comparator, possibly build by a factory method in the class to be compared.
  • if the comparison is special purpose, use Comparator

React - How to pass HTML tags in props?

You can use dangerouslySetInnerHTML

Just send the html as a normal string

<MyComponent text="This is <strong>not</strong> working." />

And render in in the JSX code like this:

<h2 className="header-title-right wow fadeInRight"
    dangerouslySetInnerHTML={{__html: props.text}} />

Just be careful if you are rendering data entered by the user. You can be victim of a XSS attack

Here's the documentation: https://facebook.github.io/react/tips/dangerously-set-inner-html.html

scp from remote host to local host

There must be a user in the AllowUsers section, in the config file /etc/ssh/ssh_config, in the remote machine. You might have to restart sshd after editing the config file.

And then you can copy for example the file "test.txt" from a remote host to the local host

scp [email protected]:test.txt /local/dir


@cool_cs you can user ~ symbol ~/Users/djorge/Desktop if it's your home dir.

In UNIX, absolute paths must start with '/'.

How to change a single value in a NumPy array?

Is this what you are after? Just index the element and assign a new value.

A[2,1]=150

A
Out[345]: 
array([[ 1,  2,  3,  4],
       [ 5,  6,  7,  8],
       [ 9, 150, 11, 12],
       [13, 14, 15, 16]])

using where and inner join in mysql

Try this :

SELECT
    (
      SELECT
          `NAME`
      FROM
          locations
      WHERE
          ID = school_locations.LOCATION_ID
    ) as `NAME`
FROM
     school_locations
WHERE
     (
      SELECT
          `TYPE`
      FROM
          locations
      WHERE
          ID = school_locations.LOCATION_ID
     ) = 'coun';

Regex for not empty and not whitespace

A little late, but here's a regex I found that returns 0 matches for empty or white spaces:

/^(?!\s*$).+/

You can test this out at regex101

Fatal error: Call to undefined function mysql_connect()

PHP.INI

Check if you forgot to enable the options below(loads the modules for mysql among others):

; Directory in which the loadable extensions (modules) reside.
; http://php.net/extension-dir
; extension_dir = "./"
; On windows:
extension_dir = "ext"

Multiprocessing vs Threading Python

The threading module uses threads, the multiprocessing module uses processes. The difference is that threads run in the same memory space, while processes have separate memory. This makes it a bit harder to share objects between processes with multiprocessing. Since threads use the same memory, precautions have to be taken or two threads will write to the same memory at the same time. This is what the global interpreter lock is for.

Spawning processes is a bit slower than spawning threads.

Error: No Firebase App '[DEFAULT]' has been created - call Firebase App.initializeApp()

I found the solution!

Follow these steps:

Flutter Firebase and Android issue - unable to Initialise. Cannot find google-services.json with latest migration instructions executed

After that, execute:

flutter build apk --debug
flutter build apk --profile
flutter build apk --release

and then, run app! it works for me!

How to change pivot table data source in Excel?

right click on the pivot table in excel choose wizard click 'back' click 'get data...' in the query window File - Table Definition

then you can create a new or choose a different connection

worked perfectly.

the get data button is next to the tiny button with a red arrow next to the range text input box.

Leading zeros for Int in Swift

Details

Xcode 9.0.1, swift 4.0

Solutions

Data

import Foundation

let array = [0,1,2,3,4,5,6,7,8]

Solution 1

extension Int {

    func getString(prefix: Int) -> String {
        return "\(prefix)\(self)"
    }

    func getString(prefix: String) -> String {
        return "\(prefix)\(self)"
    }
}

for item in array {
    print(item.getString(prefix: 0))
}

for item in array {
    print(item.getString(prefix: "0x"))
}

Solution 2

for item in array {
    print(String(repeatElement("0", count: 2)) + "\(item)")
}

Solution 3

extension String {

    func repeate(count: Int, string: String? = nil) -> String {

        if count > 1 {
            let repeatedString = string ?? self
            return repeatedString + repeate(count: count-1, string: repeatedString)
        }
        return self
    }
}

for item in array {
    print("0".repeate(count: 3) + "\(item)")
}

Changing the text on a label

You can also define a textvariable when creating the Label, and change the textvariable to update the text in the label. Here's an example:

labelText = Stringvar()
depositLabel = Label(self, textvariable=labelText)
depositLabel.grid()

def updateDepositLabel(txt) # you may have to use *args in some cases
    labelText.set(txt)

There's no need to update the text in depositLabel manually. Tk does that for you.

Android Emulator Error Message: "PANIC: Missing emulator engine program for 'x86' CPUS."

This worked for me on macOS:

echo 'export PATH=$PATH:'$HOME'/Library/Android/sdk/emulator:'$HOME'/Library/Android/sdk/tools:'$HOME'/Library/Android/sdk/platform-tools' >> ~/.bash_profile
source ~/.bash_profile

What are rvalues, lvalues, xvalues, glvalues, and prvalues?

Why are these new categories needed? Are the WG21 gods just trying to confuse us mere mortals?

I don't feel that the other answers (good though many of them are) really capture the answer to this particular question. Yes, these categories and such exist to allow move semantics, but the complexity exists for one reason. This is the one inviolate rule of moving stuff in C++11:

Thou shalt move only when it is unquestionably safe to do so.

That is why these categories exist: to be able to talk about values where it is safe to move from them, and to talk about values where it is not.

In the earliest version of r-value references, movement happened easily. Too easily. Easily enough that there was a lot of potential for implicitly moving things when the user didn't really mean to.

Here are the circumstances under which it is safe to move something:

  1. When it's a temporary or subobject thereof. (prvalue)
  2. When the user has explicitly said to move it.

If you do this:

SomeType &&Func() { ... }

SomeType &&val = Func();
SomeType otherVal{val};

What does this do? In older versions of the spec, before the 5 values came in, this would provoke a move. Of course it does. You passed an rvalue reference to the constructor, and thus it binds to the constructor that takes an rvalue reference. That's obvious.

There's just one problem with this; you didn't ask to move it. Oh, you might say that the && should have been a clue, but that doesn't change the fact that it broke the rule. val isn't a temporary because temporaries don't have names. You may have extended the lifetime of the temporary, but that means it isn't temporary; it's just like any other stack variable.

If it's not a temporary, and you didn't ask to move it, then moving is wrong.

The obvious solution is to make val an lvalue. This means that you can't move from it. OK, fine; it's named, so its an lvalue.

Once you do that, you can no longer say that SomeType&& means the same thing everwhere. You've now made a distinction between named rvalue references and unnamed rvalue references. Well, named rvalue references are lvalues; that was our solution above. So what do we call unnamed rvalue references (the return value from Func above)?

It's not an lvalue, because you can't move from an lvalue. And we need to be able to move by returning a &&; how else could you explicitly say to move something? That is what std::move returns, after all. It's not an rvalue (old-style), because it can be on the left side of an equation (things are actually a bit more complicated, see this question and the comments below). It is neither an lvalue nor an rvalue; it's a new kind of thing.

What we have is a value that you can treat as an lvalue, except that it is implicitly moveable from. We call it an xvalue.

Note that xvalues are what makes us gain the other two categories of values:

  • A prvalue is really just the new name for the previous type of rvalue, i.e. they're the rvalues that aren't xvalues.

  • Glvalues are the union of xvalues and lvalues in one group, because they do share a lot of properties in common.

So really, it all comes down to xvalues and the need to restrict movement to exactly and only certain places. Those places are defined by the rvalue category; prvalues are the implicit moves, and xvalues are the explicit moves (std::move returns an xvalue).

How do I get the path of the Python script I am running in?

7.2 of Dive Into Python: Finding the Path.

import sys, os

print('sys.argv[0] =', sys.argv[0])             
pathname = os.path.dirname(sys.argv[0])        
print('path =', pathname)
print('full path =', os.path.abspath(pathname)) 

How can I undo a mysql statement that I just executed?

You can only do so during a transaction.

BEGIN;
INSERT INTO xxx ...;
DELETE FROM ...;

Then you can either:

COMMIT; -- will confirm your changes

Or

ROLLBACK -- will undo your previous changes

Why does intellisense and code suggestion stop working when Visual Studio is open?

I had the issue in just one file. After creating the new class and working on it, it hadn't been added to the scope of my project. So when I closed and reopened my solution the following day, the file wasn't in the project scope.

Adding the existing item to the project scope fixed it for me.

Can't get private key with openssl (no start line:pem_lib.c:703:Expecting: ANY PRIVATE KEY)

I ran into the 'Expecting: ANY PRIVATE KEY' error when using openssl on Windows (Ubuntu Bash and Git Bash had the same issue).

The cause of the problem was that I'd saved the key and certificate files in Notepad using UTF8. Resaving both files in ANSI format solved the problem.

How can I get file extensions with JavaScript?

There's also a simple approach using ES6 destructuring:

_x000D_
_x000D_
const path = 'hello.world.txt'
const [extension, ...nameParts] = path.split('.').reverse();
console.log('extension:', extension);
_x000D_
_x000D_
_x000D_

Hexadecimal to Integer in Java

That's because the byte[] output is well, and array of bytes, you may think on it as an array of bytes representing each one an integer, but when you add them all into a single string you get something that is NOT an integer, that's why. You may either have it as an array of integers or try to create an instance of BigInteger.

Getting multiple values with scanf()

Passable for getting multiple values with scanf()

int r,m,v,i,e,k;

scanf("%d%d%d%d%d%d",&r,&m,&v,&i,&e,&k);

Fatal Error: Allowed Memory Size of 134217728 Bytes Exhausted (CodeIgniter + XML-RPC)

The memory allocation for PHP can be adjusted permanently, or temporarily.

Permanently

You can permanently change the PHP memory allocation two ways.

If you have access to your php.ini file, you can edit the value for memory_limit to your desire value.

If you do not have access to your php.ini file (and your webhost allows it), you can override the memory allocation through your .htaccess file. Add php_value memory_limit 128M (or whatever your desired allocation is).

Temporary

You can adjust the memory allocation on the fly from within a PHP file. You simply have the code ini_set('memory_limit', '128M'); (or whatever your desired allocation is). You can remove the memory limit (although machine or instance limits may still apply) by setting the value to "-1".

Convert datetime value into string

This is super old, but I figured I'd add my 2c. DATE_FORMAT does indeed return a string, but I was looking for the CAST function, in the situation that I already had a datetime string in the database and needed to pattern match against it:

http://dev.mysql.com/doc/refman/5.0/en/cast-functions.html

In this case, you'd use:

CAST(date_value AS char)

This answers a slightly different question, but the question title seems ambiguous enough that this might help someone searching.

postgresql port confusion 5433 or 5432?

For me in PgAdmin 4 on Mac OS High Sierra, Clicking the PostrgreSQL10 database under Servers in the left column, then the Properties tab, showed 5433 as the port under Connection. (I don't know why, because I chose 5432 during install). Anyway, I clicked the Edit icon under the Properties tab, change that to 5432, saved, and that solved the problem. Go figure.

How to iterate over a string in C?

sizeof(source) returns the number of bytes required by the pointer char*. You should replace it with strlen(source) which will be the length of the string you're trying to display.

Also, you should probably replace printf("%s",source[i]) with printf("%c",source[i]) since you're displaying a character.

PG COPY error: invalid input syntax for integer

I had this same error on a postgres .sql file with a COPY statement, but my file was tab-separated instead of comma-separated and quoted.

My mistake was that I eagerly copy/pasted the file contents from github, but in that process all the tabs were converted to spaces, hence the error. I had to download and save the raw file to get a good copy.

SQL injection that gets around mysql_real_escape_string()

Consider the following query:

$iId = mysql_real_escape_string("1 OR 1=1");    
$sSql = "SELECT * FROM table WHERE id = $iId";

mysql_real_escape_string() will not protect you against this. The fact that you use single quotes (' ') around your variables inside your query is what protects you against this. The following is also an option:

$iId = (int)"1 OR 1=1";
$sSql = "SELECT * FROM table WHERE id = $iId";

What is the difference between String and StringBuffer in Java?

A String is an immutable character array.

A StringBuffer is a mutable character array. Often converted back to String when done mutating.

Since both are an array, the maximum size for both is equal to the maximum size of an integer, which is 2^31-1 (see JavaDoc, also check out the JavaDoc for both String and StringBuffer).This is because the .length argument of an array is a primitive int. (See Arrays).

Why is AJAX returning HTTP status code 0?

"Accidental" form submission was exactly the problem I was having. I just removed the FORM tags altogether and that seems to fix the problem. Thank you, everybody!

How To change the column order of An Existing Table in SQL Server 2008

This can be an issue when using Source Control and automated deployments to a shared development environment. Where I work we have a very large sample DB on our development tier to work with (a subset of our production data).

Recently I did some work to remove one column from a table and then add some extra ones on the end. I then had to undo my column removal so I re-added it on the end which means the table and all references are correct in the environment but the Source Control automated deployment will no longer work because it complains about the table definition changing.

The real problem here is that the table + indexes are ~120GB and the environment only has ~60GB free so I'll need to either:

a) Rename the existing columns which are in the wrong order, add new columns in the right order, update the data then drop the old columns

OR

b) Rename the table, create a new table with the correct order, insert to the new table from the old and delete from the old as I go along

The SSMS/TFS Schema compare option of using a temp table won't work because there isn't enough room on disc to do it.

I'm not trying to say this is the best way to go about things or that column order really matters, just that I have a scenario where it is an issue and I'm sharing the options I've thought of to fix the issue

How to use format() on a moment.js duration?

You can use numeral.js to format your duration:

numeral(your_duration.asSeconds()).format('00:00:00') // result: hh:mm:ss

build failed with: ld: duplicate symbol _OBJC_CLASS_$_Algebra5FirstViewController

I had this same issue with a library, and I tried all of the answers listed here and nothing helped.

I ended up simply removing the library from Link Binary With Libraries and then re-adding it and it worked fine.

Why do we need the "finally" clause in Python?

They are not equivalent. Finally code is run no matter what else happens. It is useful for cleanup code that has to run.

Display encoded html with razor

Use Html.Raw(). Phil Haack posted a nice syntax guide at http://haacked.com/archive/2011/01/06/razor-syntax-quick-reference.aspx.

<div class='content'>
    @Html.Raw( Model.Content )
</div>

How to set top-left alignment for UILabel for iOS application?

In your code

label.text = @"some text";
[label sizeToFit];

Beware that if you use that in table cells or other views that get recycled with different data, you'll need to store the original frame somewhere and reset it before calling sizeToFit.

How do I pass command line arguments to a Node.js program?

Here's my 0-dep solution for named arguments:

const args = process.argv
    .slice(2)
    .map(arg => arg.split('='))
    .reduce((args, [value, key]) => {
        args[value] = key;
        return args;
    }, {});

console.log(args.foo)
console.log(args.fizz)

Example:

$ node test.js foo=bar fizz=buzz
bar
buzz

Note: Naturally this will fail when the argument contains a =. This is only for very simple usage.

Handling NULL values in Hive

What is the datatype for column1 in your Hive table? Please note that if your column is STRING it won't be having a NULL value even though your external file does not have any data for that column.

Reflection - get attribute name and value on property

to get attribute from enum, i'm using :

 public enum ExceptionCodes
 {
  [ExceptionCode(1000)]
  InternalError,
 }

 public static (int code, string message) Translate(ExceptionCodes code)
        {
            return code.GetType()
            .GetField(Enum.GetName(typeof(ExceptionCodes), code))
            .GetCustomAttributes(false).Where((attr) =>
            {
                return (attr is ExceptionCodeAttribute);
            }).Select(customAttr =>
            {
                var attr = (customAttr as ExceptionCodeAttribute);
                return (attr.Code, attr.FriendlyMessage);
            }).FirstOrDefault();
        }

// Using

 var _message = Translate(code);

How to clear a chart from a canvas so that hover events cannot be triggered?

Using CanvasJS, this works for me clearing chart and everything else, might work for you as well, granting you set your canvas/chart up fully before each processing elsewhere:

var myDiv= document.getElementById("my_chart_container{0}";
myDiv.innerHTML = "";

How to Verify if file exist with VB script

There is no built-in functionality in VBS for that, however, you can use the FileSystemObject FileExists function for that :

Option Explicit
DIM fso    
Set fso = CreateObject("Scripting.FileSystemObject")

If (fso.FileExists("C:\Program Files\conf")) Then
  WScript.Echo("File exists!")
  WScript.Quit()
Else
  WScript.Echo("File does not exist!")
End If

WScript.Quit()

Cloning an array in Javascript/Typescript

Try this

const returnedTarget = Object.assign(target, source);

and pass empty array to target

in case complex objects this way works for me

$.extend(true, [], originalArray) in case of array

$.extend(true, {}, originalObject) in case of object

Global keyboard capture in C# application

private void buttonHook_Click(object sender, EventArgs e)
{
    // Hooks only into specified Keys (here "A" and "B").
    // (***) Use this constructor

    _globalKeyboardHook = new GlobalKeyboardHook(new Keys[] { Keys.A, Keys.B });

    // Hooks into all keys.
    // (***) Or this - not both

    _globalKeyboardHook = new GlobalKeyboardHook();
    _globalKeyboardHook.KeyboardPressed += OnKeyPressed;
}

And then is working fine.

How can I view the Git history in Visual Studio Code?

I strongly recommend using a combination of GitLens & GitGraph.

Below snapshot highlights how gitlens is showing commit over time

enter image description here

And the below picture is for the the amazing vivid GitGraph

enter image description here

How to trace the path in a Breadth-First Search?

I liked qiao's first answer very much! The only thing missing here is to mark the vertexes as visited.

Why we need to do it?
Lets imagine that there is another node number 13 connected from node 11. Now our goal is to find node 13.
After a little bit of a run the queue will look like this:

[[1, 2, 6], [1, 3, 10], [1, 4, 7], [1, 4, 8], [1, 2, 5, 9], [1, 2, 5, 10]]

Note that there are TWO paths with node number 10 at the end.
Which means that the paths from node number 10 will be checked twice. In this case it doesn't look so bad because node number 10 doesn't have any children.. But it could be really bad (even here we will check that node twice for no reason..)
Node number 13 isn't in those paths so the program won't return before reaching to the second path with node number 10 at the end..And we will recheck it..

All we are missing is a set to mark the visited nodes and not to check them again..
This is qiao's code after the modification:

graph = {
    1: [2, 3, 4],
    2: [5, 6],
    3: [10],
    4: [7, 8],
    5: [9, 10],
    7: [11, 12],
    11: [13]
}


def bfs(graph_to_search, start, end):
    queue = [[start]]
    visited = set()

    while queue:
        # Gets the first path in the queue
        path = queue.pop(0)

        # Gets the last node in the path
        vertex = path[-1]

        # Checks if we got to the end
        if vertex == end:
            return path
        # We check if the current node is already in the visited nodes set in order not to recheck it
        elif vertex not in visited:
            # enumerate all adjacent nodes, construct a new path and push it into the queue
            for current_neighbour in graph_to_search.get(vertex, []):
                new_path = list(path)
                new_path.append(current_neighbour)
                queue.append(new_path)

            # Mark the vertex as visited
            visited.add(vertex)


print bfs(graph, 1, 13)

The output of the program will be:

[1, 4, 7, 11, 13]

Without the unneccecery rechecks..

How might I force a floating DIV to match the height of another floating DIV?

Wrap them in a containing div with the background color applied to it, and have a clearing div after the 'columns'.

<div style="background-color: yellow;">
  <div style="float: left;width: 65%;">column a</div>
  <div style="float: right;width: 35%;">column b</div>
  <div style="clear: both;"></div>
</div>

Updated to address some comments and my own thoughts:

This method works because its essentially a simplification of your problem, in this somewhat 'oldskool' method I put two columns in followed by an empty clearing element, the job of the clearing element is to tell the parent (with the background) this is where floating behaviour ends, this allows the parent to essentially render 0 pixels of height at the position of the clear, which will be whatever the highest priorly floating element is.

The reason for this is to ensure the parent element is as tall as the tallest column, the background is then set on the parent to give the appearance that both columns have the same height.

It should be noted that this technique is 'oldskool' because the better choice is to trigger this height calculation behaviour with something like clearfix or by simply having overflow: hidden on the parent element.

Whilst this works in this limited scenario, if you wish for each column to look visually different, or have a gap between them, then setting a background on the parent element won't work, there is however a trick to get this effect.

The trick is to add bottom padding to all columns, to the max amount of size you expect that could be the difference between the shortest and tallest column, if you can't work this out then pick a large figure, you then need to add a negative bottom margin of the same number.

You'll need overflow hidden on the parent object, but the result will be that each column will request to render this additional height suggested by the margin, but not actually request layout of that size (because the negative margin counters the calculation).

This will render the parent at the size of the tallest column, whilst allowing all the columns to render at their height + the size of bottom padding used, if this height is larger than the parent then the rest will simply clip off.

<div style="overflow: hidden;">
  <div style="background: blue;float: left;width: 65%;padding-bottom: 500px;margin-bottom: -500px;">column a<br />column a</div>
  <div style="background: red;float: right;width: 35%;padding-bottom: 500px;margin-bottom: -500px;">column b</div>
</div>

You can see an example of this technique on the bowers and wilkins website (see the four horizontal spotlight images the bottom of the page).

How would I extract a single file (or changes to a file) from a git stash?

Use the following to apply the changes to a file in a stash to your working tree.

git diff stash^! -- <filename> | git apply

This is generally better than using git checkout because you won't lose any changes you made to file since you created the stash.

How do I create a shortcut via command-line in Windows?

The best way is to run this batch file. open notepad and type:-

@echo off
echo Set oWS = WScript.CreateObject("WScript.Shell") > CreateShortcut.vbs
echo sLinkFile = "GIVETHEPATHOFLINK.lnk" >> CreateShortcut.vbs
echo Set oLink = oWS.CreateShortcut(sLinkFile) >> CreateShortcut.vbs
echo oLink.TargetPath = "GIVETHEPATHOFTARGETFILEYOUWANTTHESHORTCUT" >> CreateShortcut.vbs
echo oLink.Save >> CreateShortcut.vbs
cscript CreateShortcut.vbs
del CreateShortcut.vbs

Save as filename.bat(be careful while saving select all file types) worked well in win XP.

Meaning of ${project.basedir} in pom.xml

${project.basedir} is the root directory of your project.

${project.build.directory} is equivalent to ${project.basedir}/target

as it is defined here: https://github.com/apache/maven/blob/trunk/maven-model-builder/src/main/resources/org/apache/maven/model/pom-4.0.0.xml#L53

What's the quickest way to multiply multiple cells by another number?

Are you asking how to do it in excel or how to do it in a VBA application? If you just want to do it in excel, here is one way.

Check if Python Package is installed

Updated answer

A better way of doing this is:

import subprocess
import sys

reqs = subprocess.check_output([sys.executable, '-m', 'pip', 'freeze'])
installed_packages = [r.decode().split('==')[0] for r in reqs.split()]

The result:

print(installed_packages)

[
    "Django",
    "six",
    "requests",
]

Check if requests is installed:

if 'requests' in installed_packages:
    # Do something

Why this way? Sometimes you have app name collisions. Importing from the app namespace doesn't give you the full picture of what's installed on the system.

Note, that proposed solution works:

  • When using pip to install from PyPI or from any other alternative source (like pip install http://some.site/package-name.zip or any other archive type).
  • When installing manually using python setup.py install.
  • When installing from system repositories, like sudo apt install python-requests.

Cases when it might not work:

  • When installing in development mode, like python setup.py develop.
  • When installing in development mode, like pip install -e /path/to/package/source/.

Old answer

A better way of doing this is:

import pip
installed_packages = pip.get_installed_distributions()

For pip>=10.x use:

from pip._internal.utils.misc import get_installed_distributions

Why this way? Sometimes you have app name collisions. Importing from the app namespace doesn't give you the full picture of what's installed on the system.

As a result, you get a list of pkg_resources.Distribution objects. See the following as an example:

print installed_packages
[
    "Django 1.6.4 (/path-to-your-env/lib/python2.7/site-packages)",
    "six 1.6.1 (/path-to-your-env/lib/python2.7/site-packages)",
    "requests 2.5.0 (/path-to-your-env/lib/python2.7/site-packages)",
]

Make a list of it:

flat_installed_packages = [package.project_name for package in installed_packages]

[
    "Django",
    "six",
    "requests",
]

Check if requests is installed:

if 'requests' in flat_installed_packages:
    # Do something

BSTR to std::string (std::wstring) and vice versa

There is a c++ class called _bstr_t. It has useful methods and a collection of overloaded operators.

For example, you can easily assign from a const wchar_t * or a const char * just doing _bstr_t bstr = L"My string"; Then you can convert it back doing const wchar_t * s = bstr.operator const wchar_t *();. You can even convert it back to a regular char const char * c = bstr.operator char *(); You can then just use the const wchar_t * or the const char * to initialize a new std::wstring oe std::string.

What does "control reaches end of non-void function" mean?

Compiler by itself would not know that the conditions you have given are optimum .. meaning of this is you have covered all cases .. So therefore it always wants a return statement ... So either you can change last else if with else or just write return 0 after last else if ;`int binary(int val, int sorted[], int low, int high) { int mid = (low+high)/2;

if(high < low)
    return -1;

if(val < sorted[mid])
    return binary(val, sorted, low, mid-1);

else if(val > sorted[mid])
    return binary(val, sorted, mid+1, high);

else if(val == sorted[mid])
    return mid;
return 0; }`

How to terminate a process in vbscript

Just type in the following command: taskkill /f /im (program name) To find out the im of your program open task manager and look at the process while your program is running. After the program has run a process will disappear from the task manager; that is your program.

Displaying Image in Java

Running your code shows an image for me, after adjusting the path. Can you verify that your image path is correct, try absolute path for instance?

Read a text file using Node.js?

The async way of life:

#! /usr/bin/node

const fs = require('fs');

function readall (stream)
{
  return new Promise ((resolve, reject) => {
    const chunks = [];
    stream.on ('error', (error) => reject (error));
    stream.on ('data',  (chunk) => chunk && chunks.push (chunk));
    stream.on ('end',   ()      => resolve (Buffer.concat (chunks)));
  });
}

function readfile (filename)
{
  return readall (fs.createReadStream (filename));
}

(async () => {
  let content = await readfile ('/etc/ssh/moduli').catch ((e) => {})
  if (content)
    console.log ("size:", content.length,
                 "head:", content.slice (0, 46).toString ());
})();

How to compare two strings are equal in value, what is the best method?

You can either use the == operator or the Object.equals(Object) method.

The == operator checks whether the two subjects are the same object, whereas the equals method checks for equal contents (length and characters).

if(objectA == objectB) {
   // objects are the same instance. i.e. compare two memory addresses against each other.
}

if(objectA.equals(objectB)) {
   // objects have the same contents. i.e. compare all characters to each other 
}

Which you choose depends on your logic - use == if you can and equals if you do not care about performance, it is quite fast anyhow.

String.intern() If you have two strings, you can internate them, i.e. make the JVM create a String pool and returning to you the instance equal to the pool instance (by calling String.intern()). This means that if you have two Strings, you can call String.intern() on both and then use the == operator. String.intern() is however expensive, and should only be used as an optimalization - it only pays off for multiple comparisons.

All in-code Strings are however already internated, so if you are not creating new Strings, you are free to use the == operator. In general, you are pretty safe (and fast) with

if(objectA == objectB || objectA.equals(objectB)) {

}

if you have a mix of the two scenarios. The inline

if(objectA == null ? objectB == null : objectA.equals(objectB)) {

}

can also be quite useful, it also handles null values since String.equals(..) checks for null.

BarCode Image Generator in Java

There is a free library called barcode4j

How do I make a JAR from a .java file?

Simply with command line:

javac MyApp.java
jar -cf myJar.jar MyApp.class

Sure IDEs avoid using command line terminal

Creating a textarea with auto-resize

An even simpler, cleaner approach is this:

// adjust height of textarea.auto-height
$(document).on( 'keyup', 'textarea.auto-height', function (e){
    $(this).css('height', 'auto' ); // you can have this here or declared in CSS instead
    $(this).height( this.scrollHeight );
}).keyup();

// and the CSS

textarea.auto-height {
    resize: vertical;
    max-height: 600px; /* set as you need it */
    height: auto;      /* can be set here of in JS */
    overflow-y: auto;
    word-wrap:break-word
}

All that is needed is to add the .auto-height class to any textarea you want to target.

Tested in FF, Chrome and Safari. Let me know if this doesn't work for you, for any reason. But, this is the cleanest and simplest way I've found this to work. And it works great! :D

How to push objects in AngularJS between ngRepeat arrays

change your method to:

$scope.toggleChecked = function (index) {
    $scope.checked.push($scope.items[index]);
    $scope.items.splice(index, 1);
};

Working Demo

Grunt watch error - Waiting...Fatal error: watch ENOSPC

Any time you need to run sudo something ... to fix something, you should be pausing to think about what's going on. While the accepted answer here is perfectly valid, it's treating the symptom rather than the problem. Sorta the equivalent of buying bigger saddlebags to solve the problem of: error, cannot load more garbage onto pony. Pony has so much garbage already loaded, that pony is fainting with exhaustion.

An alternative (perhaps comparable to taking excess garbage off of pony and placing in the dump), is to run:

npm dedupe

Then go congratulate yourself for making pony happy.

android.content.Context.getPackageName()' on a null object reference

The answers to this question helped me find my problem, but my source was different, so hopefully this can shed light on someone finding this page searching for answers to the 'random' context crash:

I had specified a SharedPreferences object, and tried to instantiate it at it's class-level declaration, like so:

public class MyFragment extends FragmentActivity {
    private SharedPreferences sharedPref =
        PreferenceManager.getDefaultSharedPreferences(this);

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    //...

Referencing this before the onCreate caused the "java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.content.Context.getPackageName()' on a null object reference" error for me.

Instantiating the object inside the onCreate() solved my problem, like so:

public class MyFragment extends FragmentActivity {
    private SharedPreferences sharedPref;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //...
        sharedPref = PreferenceManager.getDefaultSharedPreferences(this);

Hope that helps.

How do I create a HTTP Client Request with a cookie?

You can do that using Requestify, a very simple and cool HTTP client I wrote for nodeJS, it support easy use of cookies and it also supports caching.

To perform a request with a cookie attached just do the following:

var requestify = require('requestify');
requestify.post('http://google.com', {}, {
    cookies: {
        sessionCookie: 'session-cookie-data'   
    }
});

How to detect when a youtube video finishes playing?

This can be done through the youtube player API:

http://jsfiddle.net/7Gznb/

Working example:

    <div id="player"></div>

    <script src="http://www.youtube.com/player_api"></script>

    <script>

        // create youtube player
        var player;
        function onYouTubePlayerAPIReady() {
            player = new YT.Player('player', {
              width: '640',
              height: '390',
              videoId: '0Bmhjf0rKe8',
              events: {
                onReady: onPlayerReady,
                onStateChange: onPlayerStateChange
              }
            });
        }

        // autoplay video
        function onPlayerReady(event) {
            event.target.playVideo();
        }

        // when video ends
        function onPlayerStateChange(event) {        
            if(event.data === 0) {          
                alert('done');
            }
        }

    </script>

I need to convert an int variable to double

Either use casting as others have already said, or multiply one of the int variables by 1.0:

double firstSolution = ((1.0* b1 * a22 - b2 * a12) / (a11 * a22 - a12 * a21));

How can I set / change DNS using the command-prompt at windows 8

Here is another way to change DNS by using WMIC (Windows Management Instrumentation Command-line).

The commands must be run as administrator to apply.

Clear DNS servers:

wmic nicconfig where (IPEnabled=TRUE) call SetDNSServerSearchOrder ()

Set 1 DNS server:

wmic nicconfig where (IPEnabled=TRUE) call SetDNSServerSearchOrder ("8.8.8.8")

Set 2 DNS servers:

wmic nicconfig where (IPEnabled=TRUE) call SetDNSServerSearchOrder ("8.8.8.8", "8.8.4.4")

Set 2 DNS servers on a particular network adapter:

wmic nicconfig where "(IPEnabled=TRUE) and (Description = 'Local Area Connection')" call SetDNSServerSearchOrder ("8.8.8.8", "8.8.4.4")

Another example for setting the domain search list:

wmic nicconfig call SetDNSSuffixSearchOrder ("domain.tld")

Codeigniter unset session

I use the old PHP way..It unsets all session variables and doesn't require to specify each one of them in an array. And after unsetting the variables we destroy the session.

session_unset();
session_destroy();

Trim a string in C

void inPlaceStrTrim(char* str) {
    int k = 0;
    int i = 0;
    for (i=0; str[i] != '\0';) {
        if (isspace(str[i])) {
            // we have got a space...
            k = i;
            for (int j=i; j<strlen(str)-1; j++) {
                str[j] = str[j+1];
            }
            str[strlen(str)-1] = '\0';
            i = k; // start the loop again where we ended..
        } else {
            i++;
        }
    }
}

How to show/hide an element on checkbox checked/unchecked states using jQuery?

    <label  onclick="chkBulk();">
    <div class="icheckbox_flat-green" style="position: relative;">
      <asp:CheckBox ID="chkBulkAssign" runat="server" class="flat" 
       Style="position: 
         absolute; opacity: 0;" />
      </div>
      Bulk Assign
     </label>



    function chkBulk() {
    if ($('[id$=chkBulkAssign]')[0].checked) {
    $('div .icheckbox_flat-green').addClass('checked');
    $("[id$=btneNoteBulkExcelUpload]").show();           
    }
   else {
   $('div .icheckbox_flat-green').removeClass('checked');
   $("[id$=btneNoteBulkExcelUpload]").hide();
   } 

C++ Get name of type in template

If you'd like a pretty_name, Logan Capaldo's solution can't deal with complex data structure: REGISTER_PARSE_TYPE(map<int,int>) and typeid(map<int,int>).name() gives me a result of St3mapIiiSt4lessIiESaISt4pairIKiiEEE

There is another interesting answer using unordered_map or map comes from https://en.cppreference.com/w/cpp/types/type_index.

#include <iostream>
#include <unordered_map>
#include <map>
#include <typeindex>
using namespace std;
unordered_map<type_index,string> types_map_;

int main(){
    types_map_[typeid(int)]="int";
    types_map_[typeid(float)]="float";
    types_map_[typeid(map<int,int>)]="map<int,int>";

    map<int,int> mp;
    cout<<types_map_[typeid(map<int,int>)]<<endl;
    cout<<types_map_[typeid(mp)]<<endl;
    return 0;
}

Sort collection by multiple fields in Kotlin

Use sortedWith to sort a list with Comparator.

You can then construct a comparator using several ways:

  • compareBy, thenBy construct the comparator in a chain of calls:

    list.sortedWith(compareBy<Person> { it.age }.thenBy { it.name }.thenBy { it.address })
    
  • compareBy has an overload which takes multiple functions:

    list.sortedWith(compareBy({ it.age }, { it.name }, { it.address }))
    

UITableView - scroll to the top

If you need use Objective-C or you still in love:

NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
    [_tableView scrollToRowAtIndexPath:indexPath atScrollPosition:UITableViewScrollPositionTop animated:YES];

How can I git stash a specific file?

To add to svick's answer, the -m option simply adds a message to your stash, and is entirely optional. Thus, the command

git stash push [paths you wish to stash]

is perfectly valid. So for instance, if I want to only stash changes in the src/ directory, I can just run

git stash push src/

Logging request/response messages when using HttpClient

See http://mikehadlow.blogspot.com/2012/07/tracing-systemnet-to-debug-http-clients.html

To configure a System.Net listener to output to both the console and a log file, add the following to your assembly configuration file:

<system.diagnostics>
  <trace autoflush="true" />
  <sources>
    <source name="System.Net">
      <listeners>
        <add name="MyTraceFile"/>
        <add name="MyConsole"/>
      </listeners>
    </source>
  </sources>
  <sharedListeners>
    <add
      name="MyTraceFile"
      type="System.Diagnostics.TextWriterTraceListener"
      initializeData="System.Net.trace.log" />
    <add name="MyConsole" type="System.Diagnostics.ConsoleTraceListener" />
  </sharedListeners>
  <switches>
    <add name="System.Net" value="Verbose" />
  </switches>
</system.diagnostics>

what is difference between success and .done() method of $.ajax

success is the callback that is invoked when the request is successful and is part of the $.ajax call. done is actually part of the jqXHR object returned by $.ajax(), and replaces success in jQuery 1.8.

Log4j2 configuration - No log4j2 configuration file found

You need to choose one of the following solutions:

  1. Put the log4j2.xml file in resource directory in your project so the log4j will locate files under class path.
  2. Use system property -Dlog4j.configurationFile=file:/path/to/file/log4j2.xml

Requested registry access is not allowed

This issue has to do with granting the necessary authorization to the user account the application runs on. To read a similar situation and a detailed response for the correct solution, as documented by Microsoft, feel free to visit this post: http://rambletech.wordpress.com/2011/10/17/requested-registry-access-is-not-allowed/

What's the syntax for mod in java

Since everyone else already gave the answer, I'll add a bit of additional context. % the "modulus" operator is actually performing the remainder operation. The difference between mod and rem is subtle, but important.

(-1 mod 2) would normally give 1. More specifically given two integers, X and Y, the operation (X mod Y) tends to return a value in the range [0, Y). Said differently, the modulus of X and Y is always greater than or equal to zero, and less than Y.

Performing the same operation with the "%" or rem operator maintains the sign of the X value. If X is negative you get a result in the range (-Y, 0]. If X is positive you get a result in the range [0, Y).

Often this subtle distinction doesn't matter. Going back to your code question, though, there are multiple ways of solving for "evenness".

The first approach is good for beginners, because it is especially verbose.

// Option 1: Clearest way for beginners
boolean isEven;
if ((a % 2) == 0)
{
  isEven = true
}
else
{
  isEven = false
}

The second approach takes better advantage of the language, and leads to more succinct code. (Don't forget that the == operator returns a boolean.)

// Option 2: Clear, succinct, code
boolean isEven = ((a % 2) == 0);

The third approach is here for completeness, and uses the ternary operator. Although the ternary operator is often very useful, in this case I consider the second approach superior.

// Option 3: Ternary operator
boolean isEven = ((a % 2) == 0) ? true : false;

The fourth and final approach is to use knowledge of the binary representation of integers. If the least significant bit is 0 then the number is even. This can be checked using the bitwise-and operator (&). While this approach is the fastest (you are doing simple bit masking instead of division), it is perhaps a little advanced/complicated for a beginner.

// Option 4: Bitwise-and
boolean isEven = ((a & 1) == 0);

Here I used the bitwise-and operator, and represented it in the succinct form shown in option 2. Rewriting it in Option 1's form (and alternatively Option 3's) is left as an exercise to the reader. ;)

Hope that helps.

Logical operator in a handlebars.js {{#if}} conditional

Unfortunately none of these solutions solve the problem of "OR" operator "cond1 || cond2".

  1. Check if first value is true
  2. Use "^" (or) and check if otherwise cond2 is true

    {{#if cond1}} DO THE ACTION {{^}} {{#if cond2}} DO THE ACTION {{/if}} {{/if}}

It breaks DRY rule. So why not use partial to make it less messy

{{#if cond1}}
    {{> subTemplate}}
{{^}}
    {{#if cond2}}
        {{> subTemplate}}
    {{/if}}
{{/if}}

What is the proper way to display the full InnerException?

buildup on nawfal 's answer.

when using his answer there was a missing variable aggrEx, I added it.

file ExceptionExtenstions.class:

// example usage:
// try{ ... } catch(Exception e) { MessageBox.Show(e.ToFormattedString()); }

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace YourNamespace
{
    public static class ExceptionExtensions
    {

        public static IEnumerable<Exception> GetAllExceptions(this Exception exception)
        {
            yield return exception;

            if (exception is AggregateException )
            {
                var aggrEx = exception as AggregateException;
                foreach (Exception innerEx in aggrEx.InnerExceptions.SelectMany(e => e.GetAllExceptions()))
                {
                    yield return innerEx;
                }
            }
            else if (exception.InnerException != null)
            {
                foreach (Exception innerEx in exception.InnerException.GetAllExceptions())
                {
                    yield return innerEx;
                }
            }
        }


        public static string ToFormattedString(this Exception exception)
        {
            IEnumerable<string> messages = exception
                .GetAllExceptions()
                .Where(e => !String.IsNullOrWhiteSpace(e.Message))
                .Select(exceptionPart => exceptionPart.Message.Trim() + "\r\n" + (exceptionPart.StackTrace!=null? exceptionPart.StackTrace.Trim():"") );
            string flattened = String.Join("\r\n\r\n", messages); // <-- the separator here
            return flattened;
        }
    }
}

Count number of records returned by group by

The simplest solution is to use a derived table:

Select Count(*)
From    (
        Select ...
        From TempTable
        Group By column_1, column_2, column_3, column_4
        ) As Z

Another solution is to use a Count Distinct:

Select ...
    , ( Select Count( Distinct column_1, column_2, column_3, column_4 )
        From TempTable ) As CountOfItems
From TempTable
Group By column_1, column_2, column_3, column_4

How to retrieve the current value of an oracle sequence without increment it?

I also tried to use CURRVAL, in my case to find out if some process inserted new rows to some table with that sequence as Primary Key. My assumption was that CURRVAL would be the fastest method. But a) CurrVal does not work, it will just get the old value because you are in another Oracle session, until you do a NEXTVAL in your own session. And b) a select max(PK) from TheTable is also very fast, probably because a PK is always indexed. Or select count(*) from TheTable. I am still experimenting, but both SELECTs seem fast.

I don't mind a gap in a sequence, but in my case I was thinking of polling a lot, and I would hate the idea of very large gaps. Especially if a simple SELECT would be just as fast.

Conclusion:

  • CURRVAL is pretty useless, as it does not detect NEXTVAL from another session, it only returns what you already knew from your previous NEXTVAL
  • SELECT MAX(...) FROM ... is a good solution, simple and fast, assuming your sequence is linked to that table

Set a div width, align div center and text align left

All of these answers should suffice. However if you don't have a defined width, auto margins will not work.

I have found this nifty little trick to centre some of the more stubborn elements (Particularly images).

.div {
   position: absolute;
   left: 0;
   right: 0;
   margin-left: 0;
   margin-right: 0;
}

batch to copy files with xcopy

You must specify your file in the copy:

xcopy C:\source\myfile.txt C:\target

Or if you want to copy all txt files for example

xcopy C:\source\*.txt C:\target

What is git tag, How to create tags & How to checkout git remote tag(s)

In order to checkout a git tag , you would execute the following command

git checkout tags/tag-name -b branch-name

eg as mentioned below.

 git checkout tags/v1.0 -b v1.0-branch

To fetch the all tags use the command

git fetch --all --tags

Error "There is already an open DataReader associated with this Command which must be closed first" when using 2 distinct commands

Add MultipleActiveResultSets=true to the provider part of your connection string. See the example below:

<add name="DbContext" connectionString="Data Source=(LocalDb)\v11.0;Initial Catalog=dbName;Persist Security Info=True;User ID=userName;Password=password;MultipleActiveResultSets=True" providerName="System.Data.SqlClient" />

How do I prevent the error "Index signature of object type implicitly has an 'any' type" when compiling typescript with noImplicitAny flag enabled?

The following tsconfig setting will allow you to ignore these errors - set it to true.

suppressImplicitAnyIndexErrors

Suppress noImplicitAny errors for indexing objects lacking index signatures.

phpMyAdmin ERROR: mysqli_real_connect(): (HY000/1045): Access denied for user 'pma'@'localhost' (using password: NO)

I am using UniServer Zero XIV 13.x.x UniController XIV V2.3.1:

enter image description here

From the command line I did this:

mysql> CREATE USER 'pmauser'@'%' IDENTIFIED BY 'MyPasswordHere!';
Query OK, 0 rows affected (0.07 sec)

mysql> GRANT ALL PRIVILEGES ON *.* TO 'pmauser'@'%' WITH GRANT OPTION;
Query OK, 0 rows affected (0.02 sec)

Then I went to C:\...\wamp\ZeroXIV_unicontroller_2_3_1\UniServerZ\home\us_opt1\config.inc.php and modified the file to have this:

/* PMA User advanced features */
//////////$cfg['Servers'][$i]['controluser']    = 'pma';
//////////$cfg['Servers'][$i]['controlpass']    = $password;
$cfg['Servers'][$i]['controluser']    = 'pmauser';
$cfg['Servers'][$i]['controlpass']    = 'MyPasswordHere!';

I restarted Apache and MySQL. The error is gone!

Angular 2 - Redirect to an external URL and open in a new tab

Another possible solution is:

const link = document.createElement('a');
link.target = '_blank';
link.href = 'https://www.google.es';
link.setAttribute('visibility', 'hidden');
link.click();

onKeyDown event not working on divs in React

You should use tabIndex attribute to be able to listen onKeyDown event on a div in React. Setting tabIndex="0" should fire your handler.

Android ADB stop application command like "force-stop" for non rooted device

The first way
Needs root

Use kill:

adb shell ps => Will list all running processes on the device and their process ids
adb shell kill <PID> => Instead of <PID> use process id of your application

The second way
In Eclipse open DDMS perspective.
In Devices view you will find all running processes.
Choose the process and click on Stop.

enter image description here

The third way
It will kill only background process of an application.

adb shell am kill [options] <PACKAGE> => Kill all processes associated with (the app's package name). This command kills only processes that are safe to kill and that will not impact the user experience.
Options are:

--user | all | current: Specify user whose processes to kill; all users if not specified.

The fourth way
Needs root

adb shell pm disable <PACKAGE> => Disable the given package or component (written as "package/class").

The fifth way
Note that run-as is only supported for apps that are signed with debug keys.

run-as <package-name> kill <pid>

The sixth way
Introduced in Honeycomb

adb shell am force-stop <PACKAGE> => Force stop everything associated with (the app's package name).

P.S.: I know that the sixth method didn't work for you, but I think that it's important to add this method to the list, so everyone will know it.

PHP: maximum execution time when importing .SQL data file

Is it a .sql file or is it compressed (.zip, .gz, etc)? Compressed formats sometimes require more PHP resources so you could try uncompressing it before uploading.

However, there are other methods you can try also. If you have command-line access, just upload the file and import with the command line client mysql (once at the mysql> prompt, use databasename; then source file.sql).

Otherwise you can use the phpMyAdmin "UploadDir" feature to put the file on the server and have it appear within phpMyAdmin without having to also upload it from your local machine.

This link has information on using UploadDir and this one has some more tips and methods.

Duplicate Symbols for Architecture arm64

to solve this problem go to Build phases and search about duplicate file like (facebookSDK , unityads ) and delete (extension file.o) then build again .

File content into unix variable with newlines

Bash -ge 4 has the mapfile builtin to read lines from the standard input into an array variable.

help mapfile 

mapfile < file.txt lines
printf "%s" "${lines[@]}"

mapfile -t < file.txt lines    # strip trailing newlines
printf "%s\n" "${lines[@]}" 

See also:

http://bash-hackers.org/wiki/doku.php/commands/builtin/mapfile

How can I put strings in an array, split by new line?

David: Great direction, but you missed \r. this worked for me:

$array = preg_split("/(\r\n|\n|\r)/", $string);

How do I convert csv file to rdd

Another alternative is to use the mapPartitionsWithIndex method as you'll get the partition index number and a list of all lines within that partition. Partition 0 and line 0 will be be the header

val rows = sc.textFile(path)
  .mapPartitionsWithIndex({ (index: Int, rows: Iterator[String]) => 
    val results = new ArrayBuffer[(String, Int)]

    var first = true
    while (rows.hasNext) {
      // check for first line
      if (index == 0 && first) {
        first = false
        rows.next // skip the first row
      } else {
        results += rows.next
      }
    }

    results.toIterator
}, true)

rows.flatMap { row => row.split(",") }

Best way in asp.net to force https for an entire site?

If you are using ASP.NET Core you could try out the nuget package SaidOut.AspNetCore.HttpsWithStrictTransportSecurity.

Then you only need to add

app.UseHttpsWithHsts(HttpsMode.AllowedRedirectForGet, configureRoutes: routeAction);

This will also add HTTP StrictTransportSecurity header to all request made using https scheme.

Example code and documentation https://github.com/saidout/saidout-aspnetcore-httpswithstricttransportsecurity#example-code

How to change time in DateTime?

Here is a method you could use to do it for you, use it like this

DateTime newDataTime = ChangeDateTimePart(oldDateTime, DateTimePart.Seconds, 0);

Here is the method, there is probably a better way, but I just whipped this up:

public enum DateTimePart { Years, Months, Days, Hours, Minutes, Seconds };
public DateTime ChangeDateTimePart(DateTime dt, DateTimePart part, int newValue)
{
    return new DateTime(
        part == DateTimePart.Years ? newValue : dt.Year,
        part == DateTimePart.Months ? newValue : dt.Month,
        part == DateTimePart.Days ? newValue : dt.Day,
        part == DateTimePart.Hours ? newValue : dt.Hour,
        part == DateTimePart.Minutes ? newValue : dt.Minute,
        part == DateTimePart.Seconds ? newValue : dt.Second
        );
}

Encrypt and decrypt a String in java

Whether encrypted be the same when plain text is encrypted with the same key depends of algorithm and protocol. In cryptography there is initialization vector IV: http://en.wikipedia.org/wiki/Initialization_vector that used with various ciphers makes that the same plain text encrypted with the same key gives various cipher texts.

I advice you to read more about cryptography on Wikipedia, Bruce Schneier http://www.schneier.com/books.html and "Beginning Cryptography with Java" by David Hook. The last book is full of examples of usage of http://www.bouncycastle.org library.

If you are interested in cryptography the there is CrypTool: http://www.cryptool.org/ CrypTool is a free, open-source e-learning application, used worldwide in the implementation and analysis of cryptographic algorithms.

What is __gxx_personality_v0 for?

A quick grep of the libstd++ code base revealed the following two usages of __gx_personality_v0:

In libsupc++/unwind-cxx.h

// GNU C++ personality routine, Version 0.                                      
extern "C" _Unwind_Reason_Code __gxx_personality_v0
     (int, _Unwind_Action, _Unwind_Exception_Class,
      struct _Unwind_Exception *, struct _Unwind_Context *);

In libsupc++/eh_personality.cc

#define PERSONALITY_FUNCTION    __gxx_personality_v0
extern "C" _Unwind_Reason_Code
PERSONALITY_FUNCTION (int version,
                      _Unwind_Action actions,
                      _Unwind_Exception_Class exception_class,
                      struct _Unwind_Exception *ue_header,
                      struct _Unwind_Context *context)
{
  // ... code to handle exceptions and stuff ...
}

(Note: it's actually a little more complicated than that; there's some conditional compilation that can change some details).

So, as long as your code isn't actually using exception handling, defining the symbol as void* won't affect anything, but as soon as it does, you're going to crash - __gxx_personality_v0 is a function, not some global object, so trying to call the function is going to jump to address 0 and cause a segfault.

The program can’t start because MSVCR71.dll is missing from your computer. Try reinstalling the program to fix this program

Here is the solution I found:

How to fix the missing MSVCR711.dll problem

You can find MSVCR71.dll file in following location of your installed SQL Developer 2.1 directory:

sqldeveloper-2.1.0.63.10\sqldeveloper\jdk\jre\bin\MSVCR71.dll

std::enable_if to conditionally compile a member function

For those late-comers that are looking for a solution that "just works":

#include <utility>
#include <iostream>

template< typename T >
class Y {

    template< bool cond, typename U >
    using resolvedType  = typename std::enable_if< cond, U >::type; 

    public:
        template< typename U = T > 
        resolvedType< true, U > foo() {
            return 11;
        }
        template< typename U = T >
        resolvedType< false, U > foo() {
            return 12;
        }

};


int main() {
    Y< double > y;

    std::cout << y.foo() << std::endl;
}

Compile with:

g++ -std=gnu++14 test.cpp 

Running gives:

./a.out 
11

How to put Google Maps V2 on a Fragment using ViewPager

The following approach works for me.

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapView;
import com.google.android.gms.maps.MapsInitializer;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.CameraPosition;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;

/**
 * A fragment that launches other parts of the demo application.
 */
public class MapFragment extends Fragment {

MapView mMapView;
private GoogleMap googleMap;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    // inflat and return the layout
    View v = inflater.inflate(R.layout.fragment_location_info, container,
            false);
    mMapView = (MapView) v.findViewById(R.id.mapView);
    mMapView.onCreate(savedInstanceState);

    mMapView.onResume();// needed to get the map to display immediately

    try {
        MapsInitializer.initialize(getActivity().getApplicationContext());
    } catch (Exception e) {
        e.printStackTrace();
    }

    googleMap = mMapView.getMap();
    // latitude and longitude
    double latitude = 17.385044;
    double longitude = 78.486671;

    // create marker
    MarkerOptions marker = new MarkerOptions().position(
            new LatLng(latitude, longitude)).title("Hello Maps");

    // Changing marker icon
    marker.icon(BitmapDescriptorFactory
            .defaultMarker(BitmapDescriptorFactory.HUE_ROSE));

    // adding marker
    googleMap.addMarker(marker);
    CameraPosition cameraPosition = new CameraPosition.Builder()
            .target(new LatLng(17.385044, 78.486671)).zoom(12).build();
    googleMap.animateCamera(CameraUpdateFactory
            .newCameraPosition(cameraPosition));

    // Perform any camera updates here
    return v;
}

@Override
public void onResume() {
    super.onResume();
    mMapView.onResume();
}

@Override
public void onPause() {
    super.onPause();
    mMapView.onPause();
}

@Override
public void onDestroy() {
    super.onDestroy();
    mMapView.onDestroy();
}

@Override
public void onLowMemory() {
    super.onLowMemory();
    mMapView.onLowMemory();
}
}

fragment_location_info.xml

<?xml version="1.0" encoding="utf-8"?>
<com.google.android.gms.maps.MapView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/mapView"
android:layout_width="match_parent"
android:layout_height="match_parent" />

curl POST format for CURLOPT_POSTFIELDS

According to the PHP manual, data passed to cURL as a string should be URLencoded. See the page for curl_setopt() and search for CURLOPT_POSTFIELDS.

Changing background colour of tr element on mouseover

<tr>s themselves are very hard to access with CSS, try tr:hover td {background:#000}

accessing a docker container from another container

Easiest way is to use --link, however the newer versions of docker are moving away from that and in fact that switch will be removed soon.

The link below offers a nice how too, on connecting two containers. You can skip the attach portion, since that is just a useful how to on adding items to images.

https://deis.com/blog/2016/connecting-docker-containers-1/

The part you are interested in is the communication between two containers. The easiest way, is to refer to the DB container by name from the webserver container.

Example:

you named the db container db1 and the webserver container web0. The containers should both be on the bridge network, which means the web container should be able to connect to the DB container by referring to it's name.

So if you have a web config file for your app, then for DB host you will use the name db1.

if you are using an older version of docker, then you should use --link.

Example:

Step 1: docker run --name db1 oracle/database:12.1.0.2-ee

then when you start the web app. use:

Step 2: docker run --name web0 --link db1 webapp/webapp:3.0

and the web app will be linked to the DB. However, as I said the --link switch will be removed soon.

I'd use docker compose instead, which will build a network for you. However; you will need to download docker compose for your system. https://docs.docker.com/compose/install/#prerequisites

an example setup is like this:

file name is base.yml

version: "2"
services:
  webserver:
    image: "moodlehq/moodle-php-apache:7.1
    depends_on:
      - db
    volumes:
      - "/var/www/html:/var/www/html"
      - "/home/some_user/web/apache2_faildumps.conf:/etc/apache2/conf-enabled/apache2_faildumps.conf"
    environment:
      MOODLE_DOCKER_DBTYPE: pgsql
      MOODLE_DOCKER_DBNAME: moodle
      MOODLE_DOCKER_DBUSER: moodle
      MOODLE_DOCKER_DBPASS: "m@0dl3ing"
      HTTP_PROXY: "${HTTP_PROXY}"
      HTTPS_PROXY: "${HTTPS_PROXY}"
      NO_PROXY: "${NO_PROXY}"
  db:
    image: postgres:9
    environment:
      POSTGRES_USER: moodle
      POSTGRES_PASSWORD: "m@0dl3ing"
      POSTGRES_DB: moodle
      HTTP_PROXY: "${HTTP_PROXY}"
      HTTPS_PROXY: "${HTTPS_PROXY}"
      NO_PROXY: "${NO_PROXY}"

this will name the network a generic name, I can't remember off the top of my head what that name is, unless you use the --name switch.

IE docker-compose --name setup1 up base.yml

NOTE: if you use the --name switch, you will need to use it when ever calling docker compose, so docker-compose --name setup1 down this is so you can have more then one instance of webserver and db, and in this case, so docker compose knows what instance you want to run commands against; and also so you can have more then one running at once. Great for CI/CD, if you are running test in parallel on the same server.

Docker compose also has the same commands as docker so docker-compose --name setup1 exec webserver do_some_command

best part is, if you want to change db's or something like that for unit test you can include an additional .yml file to the up command and it will overwrite any items with similar names, I think of it as a key=>value replacement.

Example:

db.yml

version: "2"
services:
  webserver:
    environment:
      MOODLE_DOCKER_DBTYPE: oci
      MOODLE_DOCKER_DBNAME: XE
  db:
    image: moodlehq/moodle-db-oracle

Then call docker-compose --name setup1 up base.yml db.yml

This will overwrite the db. with a different setup. When needing to connect to these services from each container, you use the name set under service, in this case, webserver and db.

I think this might actually be a more useful setup in your case. Since you can set all the variables you need in the yml files and just run the command for docker compose when you need them started. So a more start it and forget it setup.

NOTE: I did not use the --port command, since exposing the ports is not needed for container->container communication. It is needed only if you want the host to connect to the container, or application from outside of the host. If you expose the port, then the port is open to all communication that the host allows. So exposing web on port 80 is the same as starting a webserver on the physical host and will allow outside connections, if the host allows it. Also, if you are wanting to run more then one web app at once, for whatever reason, then exposing port 80 will prevent you from running additional webapps if you try exposing on that port as well. So, for CI/CD it is best to not expose ports at all, and if using docker compose with the --name switch, all containers will be on their own network so they wont collide. So you will pretty much have a container of containers.

UPDATE: After using features further and seeing how others have done it for CICD programs like Jenkins. Network is also a viable solution.

Example:

docker network create test_network

The above command will create a "test_network" which you can attach other containers too. Which is made easy with the --network switch operator.

Example:

docker run \
    --detach \
    --name db1 \
    --network test_network \
    -e MYSQL_ROOT_PASSWORD="${DBPASS}" \
    -e MYSQL_DATABASE="${DBNAME}" \
    -e MYSQL_USER="${DBUSER}" \
    -e MYSQL_PASSWORD="${DBPASS}" \
    --tmpfs /var/lib/mysql:rw \
    mysql:5

Of course, if you have proxy network settings you should still pass those into the containers using the "-e" or "--env-file" switch statements. So the container can communicate with the internet. Docker says the proxy settings should be absorbed by the container in the newer versions of docker; however, I still pass them in as an act of habit. This is the replacement for the "--link" switch which is going away. Once the containers are attached to the network you created you can still refer to those containers from other containers using the 'name' of the container. Per the example above that would be db1. You just have to make sure all containers are connected to the same network, and you are good to go.

For a detailed example of using network in a cicd pipeline, you can refer to this link: https://git.in.moodle.com/integration/nightlyscripts/blob/master/runner/master/run.sh

Which is the script that is ran in Jenkins for a huge integration tests for Moodle, but the idea/example can be used anywhere. I hope this helps others.

Undefined index error PHP

TRY

<?php

  $rowID=$productid=$name=$price=$description="";  

   if (isset($_POST['submit'])) {
      $rowID = $_POST['rowID'];
      $productid = $_POST['productid']; //this is line 32 and so on...
      $name = $_POST['name'];
      $price = $_POST['price'];
      $description = $_POST['description'];

}

Pass array to MySQL stored routine

You can pass a string with your list and use a prepared statements to run a query, e.g. -

DELIMITER $$

CREATE PROCEDURE GetFruits(IN fruitArray VARCHAR(255))
BEGIN

  SET @sql = CONCAT('SELECT * FROM Fruits WHERE Name IN (', fruitArray, ')');
  PREPARE stmt FROM @sql;
  EXECUTE stmt;
  DEALLOCATE PREPARE stmt;

END
$$

DELIMITER ;

How to use:

SET @fruitArray = '\'apple\',\'banana\'';
CALL GetFruits(@fruitArray);

Why am I not getting a java.util.ConcurrentModificationException in this example?

One way to handle it it to remove something from a copy of a Collection (not Collection itself), if applicable. Clone the original collection it to make a copy via a Constructor.

This exception may be thrown by methods that have detected concurrent modification of an object when such modification is not permissible.

For your specific case, first off, i don't think final is a way to go considering you intend to modify the list past declaration

private static final List<Integer> integerList;

Also consider modifying a copy instead of the original list.

List<Integer> copy = new ArrayList<Integer>(integerList);

for(Integer integer : integerList) {
    if(integer.equals(remove)) {                
        copy.remove(integer);
    }
}

How to securely save username/password (local)?

This only works on Windows, so if you are planning to use dotnet core cross-platform, you'll have to look elsewhere. See https://github.com/dotnet/corefx/blob/master/Documentation/architecture/cross-platform-cryptography.md

PL/SQL block problem: No data found error

When you are selecting INTO a variable and there are no records returned you should get a NO DATA FOUND error. I believe the correct way to write the above code would be to wrap the SELECT statement with it's own BEGIN/EXCEPTION/END block. Example:

...
v_final_grade NUMBER;
v_letter_grade CHAR(1);
BEGIN

    BEGIN
    SELECT final_grade
      INTO v_final_grade
      FROM enrollment
     WHERE student_id = v_student_id
       AND section_id = v_section_id;

    EXCEPTION
      WHEN NO_DATA_FOUND THEN
        v_final_grade := NULL;
    END;

    CASE -- outer CASE
      WHEN v_final_grade IS NULL THEN
      ...

Proper way to renew distribution certificate for iOS

Your live apps will not be taken down. Nothing will happen to anything that is live in the app store.

Once they formally expire, the only thing that will be impacted is your ability to sign code (and thus make new builds and provide updates).

Regarding your distribution certificate, once it expires, it simply disappears from the ‘Certificates, Identifier & Profiles’ section of Member Center. If you want to renew it before it expires, revoke the current certificate and you will get a button to request a new one.

Regarding the provisioning profile, don't worry about it before expiration, just keep using it. It's easy enough to just renew it once it expires.

The peace of mind is that nothing will happen to your live app in the store.

Get the real width and height of an image with JavaScript? (in Safari/Chrome)

Another suggestion is to use imagesLoaded plugin.

$("img").imagesLoaded(function(){
alert( $(this).width() );
alert( $(this).height() );
});

How to know if a Fragment is Visible?

Just in case you use a Fragment layout with a ViewPager (TabLayout), you can easily ask for the current (in front) fragment by ViewPager.getCurrentItem() method. It will give you the page index.

Mapping from page index to fragment[class] should be easy as you did the mapping in your FragmentPagerAdapter derived Adapter already.

int i = pager.getCurrentItem();

You may register for page change notifications by

ViewPager pager = (ViewPager) findViewById(R.id.container);
pager.addOnPageChangeListener(this);

Of course you must implement interface ViewPager.OnPageChangeListener

public class MainActivity 
    extends AppCompatActivity
    implements ViewPager.OnPageChangeListener
{
    public void onPageSelected (int position)
    {
        // we get notified here when user scrolls/switches Fragment in ViewPager -- so
        // we know which one is in front.
        Toast toast = Toast.makeText(this, "current page " + String.valueOf(position), Toast.LENGTH_LONG);
        toast.show();
    }

    public void onPageScrolled (int position, float positionOffset, int positionOffsetPixels) {
    }

    public void onPageScrollStateChanged (int state) {
    }
}

My answer here might be a little off the question. But as a newbie to Android Apps I was just facing exactly this problem and did not find an answer anywhere. So worked out above solution and posting it here -- perhaps someone finds it useful.

Edit: You might combine this method with LiveData on which the fragments subscribe. Further on, if you give your Fragments a page index as constructor argument, you can make a simple amIvisible() function in your fragment class.

In MainActivity:

private final MutableLiveData<Integer> current_page_ld = new MutableLiveData<>();
public LiveData<Integer> getCurrentPageIdx() { return current_page_ld; }

public void onPageSelected(int position) {
    current_page_ld.setValue(position);
}

public class MyPagerAdapter extends FragmentPagerAdapter
{
    public Fragment getItem(int position) {
        // getItem is called to instantiate the fragment for the given page: But only on first
        // creation -- not on restore state !!!
        // see: https://stackoverflow.com/a/35677363/3290848
        switch (position) {
            case 0:
                return MyFragment.newInstance(0);
            case 1:
                return OtherFragment.newInstance(1);
            case 2:
                return XYFragment.newInstance(2);
        }
        return null;
    }
}

In Fragment:

    public static MyFragment newInstance(int index) {
        MyFragment fragment = new MyFragment();
        Bundle args = new Bundle();
        args.putInt("idx", index);
        fragment.setArguments(args);
        return fragment;
    }

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (getArguments() != null) {
            mPageIndex = getArguments().getInt(ARG_PARAM1);
        }
        ...
    }
    
    public void onAttach(Context context)
    {
        super.onAttach(context);
        MyActivity mActivity = (MyActivity)context;

        mActivity.getCurrentPageIdx().observe(this, new Observer<Integer>() {
            @Override
            public void onChanged(Integer data) {
                if (data == mPageIndex) {
                    // have focus
                } else {
                    // not in front
                }
            }
        });
    }

How to view user privileges using windows cmd?

Mark Russinovich wrote a terrific tool called AccessChk that lets you get this information from the command line. No installation is necessary.

http://technet.microsoft.com/en-us/sysinternals/bb664922.aspx

For example:

accesschk.exe /accepteula -q -a SeServiceLogonRight

Returns this for me:

IIS APPPOOL\DefaultAppPool
IIS APPPOOL\Classic .NET AppPool
NT SERVICE\ALL SERVICES

By contrast, whoami /priv and whoami /all were missing some entries for me, like SeServiceLogonRight.

How to check if type is Boolean

If you just want to check for a primitive value

typeof variable === 'boolean'

If for some strange reason you have booleans created with the constructor, those aren't really booleans but objects containing a primitive boolean value, and one way to check for both primitive booleans and objects created with new Boolean is to do :

function checkBool(bool) {
    return typeof bool === 'boolean' || 
           (typeof bool === 'object' && 
            bool !== null            &&
           typeof bool.valueOf() === 'boolean');
}

_x000D_
_x000D_
function checkBool(bool) {_x000D_
    return typeof bool === 'boolean' || _x000D_
           (typeof bool === 'object' && _x000D_
            bool !== null            &&_x000D_
           typeof bool.valueOf() === 'boolean');_x000D_
}_x000D_
_x000D_
console.log( checkBool( 'string'          )); // false, string_x000D_
console.log( checkBool( {test: 'this'}    )); // false, object_x000D_
console.log( checkBool( null              )); // false, null_x000D_
console.log( checkBool( undefined         )); // false, undefined_x000D_
console.log( checkBool( new Boolean(true) )); // true_x000D_
console.log( checkBool( new Boolean()     )); // true_x000D_
console.log( checkBool( true              )); // true_x000D_
console.log( checkBool( false             )); // true
_x000D_
_x000D_
_x000D_

DataGridView changing cell background color

dataGridView1.Rows[i].Cells[7].Style.BackColor = Color.LightGreen;

How to change progress bar's progress color in Android

Hit the same problem while working on modifying the look/feel of the default progress bar. Here is some more info that will hopefully help people :)

  • The name of the xml file must only contain characters: a-z0-9_. (ie. no capitals!)
  • To reference your "drawable" it is R.drawable.filename
  • To override the default look, you use myProgressBar.setProgressDrawable(...), however you need can't just refer to your custom layout as R.drawable.filename, you need to retrieve it as a Drawable:
    Resources res = getResources();
    myProgressBar.setProgressDrawable(res.getDrawable(R.drawable.filename);
    
  • You need to set style before setting progress/secondary progress/max (setting it afterwards for me resulted in an 'empty' progress bar)

Bring a window to the front in WPF

Remember not to put the code that shows that window inside a PreviewMouseDoubleClick handler as the active window will switch back to the window who handled the event. Just put it in the MouseDoubleClick event handler or stop bubbling by setting e.Handled to True.

In my case i was handling the PreviewMouseDoubleClick on a Listview and was not setting the e.Handled = true then it raised the MouseDoubleClick event witch sat focus back to the original window.

show icon in actionbar/toolbar with AppCompat-v7 21

Try this. For me it worked

getSupportActionBar().setDisplayShowHomeEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayUseLogoEnabled(true);

Inserting into Oracle and retrieving the generated sequence ID

You can use the below statement to get the inserted Id to a variable-like thing.

INSERT INTO  YOUR_TABLE(ID) VALUES ('10') returning ID into :Inserted_Value;

Now you can retrieve the value using the below statement

SELECT :Inserted_Value FROM DUAL;

changing kafka retention period during runtime

I tested and used this command in kafka confluent V4.0.0 and apache kafka V 1.0.0 and 1.0.1

/opt/kafka/confluent-4.0.0/bin/kafka-configs --zookeeper XX.XX.XX.XX:2181 --entity-type topics --entity-name test --alter --add-config  retention.ms=55000

test is the topic name.

I think it works well in other versions too

Can we create an instance of an interface in Java?

Yes, your example is correct. Anonymous classes can implement interfaces, and that's the only time I can think of that you'll see a class implementing an interface without the "implements" keyword. Check out another code sample right here:

interface ProgrammerInterview {
    public void read();
}

class Website {
    ProgrammerInterview p = new ProgrammerInterview() {
        public void read() {
            System.out.println("interface ProgrammerInterview class implementer");
        }
    };
}

This works fine. Was taken from this page:

http://www.programmerinterview.com/index.php/java-questions/anonymous-class-interface/

New line character in VB.Net?

Environment.NewLine is the most ".NET" way of getting the character, it will also emit a carriage return and line feed on Windows and just a carriage return in Unix if this is a concern for you.

However, you can also use the VB6 style vbCrLf or vbCr, giving a carriage return and line feed or just a carriage return respectively.

What does "./" (dot slash) refer to in terms of an HTML file path location?

For example css files are in folder named CSS and html files are in folder HTML, and both these are in folder named XYZ means we refer css files in html as

<link rel="stylesheet" type="text/css" href="./../CSS/style.css" />

Here .. moves up to HTML
and . refers to the current directory XYZ

---by this logic you would just reference as:

<link rel="stylesheet" type="text/css" href="CSS/style.css" />

Detect if a browser in a mobile device (iOS/Android phone/tablet) is used

Simple! Throw this at the like, bottom of your CSS file and this part of the CSS will be modified within a phone: -

/* ON A PHONE */
@media only screen and (max-width: 600px) { /* CSS HERE ONLY ON PHONE */ }

And voila!

How to launch jQuery Fancybox on page load?

The best way I've found is:

<script type="text/javascript">
    $(document).ready(function() {
        $.fancybox(
             $("#WRAPPER_FOR_hidden_div_with_content_to_show").html(), //fancybox works perfect with hidden divs
             {
                  //fancybox options
             }
        );
    });
</script>

How do you put an image file in a json object?

The JSON format can contain only those types of value:

  • string
  • number
  • object
  • array
  • true
  • false
  • null

An image is of the type "binary" which is none of those. So you can't directly insert an image into JSON. What you can do is convert the image to a textual representation which can then be used as a normal string.

The most common way to achieve that is with what's called base64. Basically, instead of encoding it as 1 and 0s, it uses a range of 64 characters which makes the textual representation of it more compact. So for example the number '64' in binary is represented as 1000000, while in base64 it's simply one character: =.

There are many ways to encode your image in base64 depending on if you want to do it in the browser or not.

Note that if you're developing a web application, it will be way more efficient to store images separately in binary form, and store paths to those images in your JSON or elsewhere. That also allows your client's browser to cache the images.

Difficulty with ng-model, ng-repeat, and inputs

If you don't need the model to update with every key-stroke, just bind to name and then update the array item on blur event:

<div ng-repeat="name in names">
    Value: {{name}}
    <input ng-model="name" ng-blur="names[$index] = name" />
</div>

Error while waiting for device: Time out after 300seconds waiting for emulator to come online

The solution for me was setting the Graphics option on the Android Virtual Device to Software instead of Automatic or Hardware.

I believe this was the solution because I am working on a windows machine that did not have a dedicated graphics card.

How to commit a change with both "message" and "description" from the command line?

git commit -a -m "Your commit message here"

will quickly commit all changes with the commit message. Git commit "title" and "description" (as you call them) are nothing more than just the first line, and the rest of the lines in the commit message, usually separated by a blank line, by convention. So using this command will just commit the "title" and no description.

If you want to commit a longer message, you can do that, but it depends on which shell you use.

In bash the quick way would be:

git commit -a -m $'Commit title\n\nRest of commit message...'

SQL Query to fetch data from the last 30 days?

Pay attention to one aspect when doing "purchase_date>(sysdate-30)": "sysdate" is the current date, hour, minute and second. So "sysdate-30" is not exactly "30 days ago", but "30 days ago at this exact hour".

If your purchase dates have 00.00.00 in hours, minutes, seconds, better doing:

where trunc(purchase_date)>trunc(sysdate-30)

(this doesn't take hours, minutes and seconds into account).