Because you create the RegExp using a String the `_\-\.` becomes `_-.`  and that is the invalid range.
(It is a range from `_`  to `.` and that is not correct)

You need to _double escape_ it:

&lt;!-- language: lang-js --&gt;

    new RegExp(&quot;^([A-Za-z0-9_\\-\\.])+@&quot; + domain + &quot;$&quot;);

That way the `\\` becomes a `\` in the String and then is used to escape the `-`in the RegExp.

**EDIT:**

If you create RegExp by String it is always helpful to log the result so that you see if you did everything right:

e.g. your part of the RegExp

&lt;!-- language: lang-js --&gt;

    console.log(&quot;^([A-Za-z0-9_\-\.])+\@&quot;);

results in:

&lt;!-- language: lang-none --&gt;
  
    ^([A-Za-z0-9_-.])+@
   

I&#39;d like to add option to a select dynamically using plain javascript.  Everything I could find involves JQuery or tries to create the select dynamically as well.  The closest thing I could find was https://stackoverflow.com/questions/7340644/dynamically-add-input-type-select-with-options-in-javascript which does the latter and was the only I found that doesn&#39;t involve JQuery.  Although I did try and use it like so:

    daySelect = document.getElementById(&#39;daySelect&#39;);
    daySelect.innerHTML += &quot;&lt;option&#39;&gt;Hello world&lt;/option&#39;&gt;&quot;;
    alert(daySelect.innerHTML)

After I did this there was no change to the select and the alert gave me 

    HELLO WORLD&lt;/option&#39;&gt;

I apologize if this is simple but I&#39;m very new at javascript and web programming in general.  Thank you for any assistance.

EDIT: So I tried the given suggestions like so.

    daySelect = document.getElementById(&#39;daySelect&#39;);
    myOption = document.createElement(&quot;option&quot;);
    myOption.text = &quot;Hello World&quot;;
    myOption.value = &quot;Hello World&quot;;
    daySelect.appendChild(myOption);

This has not changed the select in the page at all.  Any idea why?  And I did check that the code was being run with an alert.

EDIT: The idea did work, it just turned out that it wasn&#39;t displaying a value in the dropdown.  I don&#39;t know why but I can figure that one out I think.

how to dynamically add options to an existing select in vanilla javascript

I have a button and a text-view, text-view has a drawable-left.
After click on button the drawable-left should be removed and a plain text should be set to Text-view, but I don’t know how to remove drawable-left from code.

Thanks in advance.

How to remove drawableleft

I don&#39;t know why my regex is incorrect:

    var domain = &quot;google\.com\.br&quot;;
    var reEmail = new RegExp(&quot;^([A-Za-z0-9_\-\.])+\@&quot; + domain + &quot;$&quot;);

I need this to validate an email. Example below: `reEmail.test(&quot;contact@google.com.br&quot;);`

I get this error:

**Range out of order in character class**

Range out of order in character class in javascript

I don't know why my regex is incorrect:
<pre><code class="hljs language-ini">var domain = "google\.com\.br";
var reEmail = new RegExp("^([A-Za-z0-9_\-\.])+\@" + domain + "$");
</code></pre>
I need this to validate an email. Example below: <code>reEmail.test("contact@google.com.br");</code>
I get this error:
Range out of order in character class

I&#39;ve been searching for 4 hours now, and have not found a solution to get the difference between two dates in years, months, and days in JavaScript, like: 10th of April 2010 was 3 years, x month and y days ago.

There are lots of solutions, but they only offer the difference in the format of either days OR months OR years, or they are not correct (meaning not taking care of actual number of days in a month or leap years, etc). Is it really that difficult to do that? 


I&#39;ve had a look at: 

 - http://momentjs.com/ -&gt; can only output the difference in either years, months, OR days
 - http://www.javascriptkit.com/javatutors/datedifference.shtml
 - http://www.javascriptkit.com/jsref/date.shtml
 - http://timeago.yarp.com/
 - www.stackoverflow.com -&gt; Search function

In php it is easy, but unfortunately I can only use client-side script on that project. Any library or framework that can do it would be fine, too.

Here are a list of expected outputs for date differences:

    //Expected output should be: &quot;1 year, 5 months&quot;.
    diffDate(new Date(&#39;2014-05-10&#39;), new Date(&#39;2015-10-10&#39;));
    
    //Expected output should be: &quot;1 year, 4 months, 29 days&quot;.
    diffDate(new Date(&#39;2014-05-10&#39;), new Date(&#39;2015-10-09&#39;));
    
    //Expected output should be: &quot;1 year, 3 months, 30 days&quot;.
    diffDate(new Date(&#39;2014-05-10&#39;), new Date(&#39;2015-09-09&#39;));
    
    //Expected output should be: &quot;9 months, 27 days&quot;.
    diffDate(new Date(&#39;2014-05-10&#39;), new Date(&#39;2015-03-09&#39;));
    
    //Expected output should be: &quot;1 year, 9 months, 28 days&quot;.
    diffDate(new Date(&#39;2014-05-10&#39;), new Date(&#39;2016-03-09&#39;));
    
    //Expected output should be: &quot;1 year, 10 months, 1 days&quot;.
    diffDate(new Date(&#39;2014-05-10&#39;), new Date(&#39;2016-03-11&#39;));

Difference between two dates in years, months, days in JavaScript

Is it possible to use smooth scroll to anchor links but **without** `jQuery`? I am creating a new site and I don&#39;t want to use `jQuery`.

Smooth scroll anchor links WITHOUT jQuery

I am using **jspdf** to generate a pdf file. Every thing is working fine. But how to open generated 
pdf in new tab or new window.

I am using 

    doc.output(&#39;datauri&#39;);

Which is opening the pdf in same tab.



How to open generated pdf using jspdf in new window

I want to show all of the keys and storage written before. 
My code is below. I created a function (allStorage) but it doesn&#39;t work. 
How can I do this? 


        function storeUserScribble(id) {
            var scribble = document.getElementById(&#39;scribble&#39;).innerHTML;
            localStorage.setItem(&#39;userScribble&#39;,scribble);
        }

        function getUserScribble() {
            if ( localStorage.getItem(&#39;userScribble&#39;)) {
                var scribble = localStorage.getItem(&#39;userScribble&#39;);
            }
            else {
                var scribble = &#39;You can scribble directly on this sticky... and I will also remember your message the next time you visit my blog!&#39;;
            }
            document.getElementById(&#39;scribble&#39;).innerHTML = scribble;
        }

        function clearLocal() {
            localStorage.clear();
            return false;
        }

        function allStorage() {
            var archive = [];
            for (var i = 0; i&lt;localStorage.length; i++) {
                archive[i] = localStorage.getItem(localStorage.key(i));
            }
        }



How to retrieve all localStorage items without knowing the keys in advance?

I am trying to write a regular expression which returns a string which is between parentheses. For example: I want to get the string which resides between the strings &quot;(&quot; and &quot;)&quot;

    I expect five hundred dollars ($500).

would return

    $500

Found https://stackoverflow.com/questions/5642315/regular-expression-to-get-a-string-between-two-strings-in-javascript

But I&#39;m new with regex. I don&#39;t know how to use &#39;(&#39;, &#39;)&#39; in regexp

Regular Expression to get a string between parentheses in Javascript

I have a bunch of labels in a text file (e.g. MY LABEL:) that I need to make title case.

I already know how I would make them all lower or upper case.

For example:

`^([A-Z &amp;#]+:)` to `\L$1`

However, is there a simple switch-based way to get title case?

Sublime Text: Regex to convert Uppercase to Title Case?

In the regex below, `\s` denotes a space character.  I imagine the regex parser, is going through the string and sees `\` and knows that the next character is special.

But this is not the case as double escapes are required.

Why is this?

    var res = new RegExp(&#39;(\\s|^)&#39; + foo).test(moo);

Is there a concrete example of how a single escape could be mis-interpreted as something else?

Why do regex constructors need to be double escaped?

I want to **add a (variable) tag** to values with regex, the pattern works fine with PHP but I have troubles implementing it into JavaScript.

The pattern is (`value` is the variable):

    /(?!(?:[^&lt;]+&gt;|[^&gt;]+&lt;\/a&gt;))\b(value)\b/is

I escaped the backslashes:

    var str = $(&quot;#div&quot;).html();
    var regex = &quot;/(?!(?:[^&lt;]+&gt;|[^&gt;]+&lt;\\/a&gt;))\\b(&quot; + value + &quot;)\\b/is&quot;;
    $(&quot;#div&quot;).html(str.replace(regex, &quot;&lt;a href=&#39;#&quot; + value +&quot;&gt;&quot; + value + &quot;&lt;/a&gt;&quot;));

But this seem not to be right, I logged the pattern and its exactly what it should be.
Any ideas?

Use dynamic (variable) string as regex pattern in JavaScript

I&#39;m trying to match some lines against regex that contains digits.

Bash version 3.2.25:

    #!/bin/bash
    
    s=&quot;AAA (bbb 123) CCC&quot;
    regex=&quot;AAA $bbb \d+$ CCC&quot;
    if [[ $s =~ $regex ]]; then
      echo $s matches $regex
    else
      echo $s doesnt match $regex
    fi

Result:

    AAA (bbb 123) CCC doesnt match AAA $bbb \d+$ CCC


If I put `regex=&quot;AAA $bbb .+$ CCC&quot;` it works but it doesn&#39;t meet my requirement to match digits only.

Why doesn&#39;t `\d+` match `123`?

How to match digits in regex in bash script

I have the class with validation:
    
   

    public class User {
    	@Size(min=3, max=20, message=&quot;User name must be between 3 and 20 characters long&quot;)
    	@Pattern(regexp=&quot;^[a-zA-Z0-9]+$&quot;, message=&quot;User name must be alphanumeric with no spaces&quot;)
    	private String name;
    	
    	@Size(min=6, max=20, message=&quot;Password must be between 6 and 20 characters long&quot;)
    	@Pattern(regexp=&quot;^(?=.*[0-9])(?=.*[a-zA-Z])([a-zA-Z0-9]+)$&quot;, message=&quot;Password must contains at least one number&quot;)
    	private String password;
    	
    	public User(String _name, String _password){
    		super();
    		name = _name;
    		password = _password;
    	}
    	
    	public String getName(){
    		return name;
    	}
    	
    	public String getPassword(){
    		return password;
    	}
    	
    	public void setPassword(String newPassword){
    		password = newPassword;
    	}
    
    }

when I validate values, I got the message:

    SEVERE: Servlet.service() for servlet osAppServlet threw exception
    java.lang.NoSuchMethodException: userAuth.User.&lt;init&gt;()

where is the problem?

java.lang.NoSuchMethodException: userAuth.User.&lt;init&gt;()

I added a validation to an objects using:

    validate :field, presence: true

I found they do not give error messages. I changed them to `validates` and got the error messages. [This ticket][1] is relevant.

I tried to add a custom validation with `validates` and got an error:

    You need to supply at least one validation

I changed it to `validate`, and everything went along as expected.

My understanding is to use `validates` with normal validations, and `validate` with custom ones. Is that right? Are there any other pieces I should know about? Is there any way to have the first problem fail loudly and not just validate everything?

  [1]: https://rails.lighthouseapp.com/projects/8994/tickets/4438-30-validates-vs-validate

What&#39;s the difference between &quot;validate&quot; and &quot;validates&quot;?

I have the following code in an AngularJS application, inside of a controller,
which is called from an ng-submit function, which belongs to a form with name `profileForm`:

    $scope.updateProfile = function() {
      if($scope.profileForm.$invalid) { 
        //error handling..
      }
      //etc.
    };


Inside of this function, is there any way to figure out which fields are causing the entire form to be called invalid?


AngularJS: Is there any way to determine which fields are making a form invalid?

I&#39;ve carefully read the JSON description http://json.org/ but I&#39;m not sure I know the answer to the simple question. What strings are the minimum possible valid JSON?

 * `&quot;string&quot;` is the string valid JSON?
 * `42` is the simple number valid JSON?
 * `true` is the boolean value a valid JSON?
 * `{}` is the empty object a valid JSON?
 * `[]` is the empty array a valid JSON?

What is the minimum valid JSON?

I am trying to mark a `text` input box as **required** in Javascript.

    &lt;input id=&quot;edName&quot; type=&quot;text&quot; id=&quot;name&quot;&gt;

If the field is initially marked as `required`:

    &lt;form&gt;
        &lt;input id=&quot;edName&quot; type=&quot;text&quot; id=&quot;name&quot; required&gt;&lt;br&gt;
        &lt;input type=&quot;submit&quot; value=&quot;Search&quot;&gt;
    &lt;/form&gt;

when the user tries to submit they are given a validation error:

![enter image description here][1]

But now I want to set the `required` attribute at *&quot;runtime&quot;*, through Javascript:

    &lt;form&gt;
        &lt;input id=&quot;edName&quot; type=&quot;text&quot; id=&quot;name&quot;&gt;&lt;br&gt;
        &lt;input type=&quot;submit&quot; value=&quot;Search&quot;&gt;
    &lt;/form&gt;

with the corresponding script:

    //recommended W3C HTML5 syntax for boolean attributes
    document.getElementById(&quot;edName&quot;).attributes[&quot;required&quot;] = &quot;&quot;;         

Except when I submit now, there is no validation check, no block.

What is the *correct* way to set an *HTML5 validation boolean attribute*?

[jsFiddle](http://jsfiddle.net/CP7sR/3/)


What&#39;s the value of the attribute, you ask?
==========

The HTML5 validation [`required` attribute is documented](http://www.w3.org/TR/html5/forms.html#the-required-attribute) as a `Boolean`:

&gt; **4.10.7.3.4 The [`required`][2] attribute**
&gt; -------------------
&gt; 
&gt; The **`required`** attribute is a [boolean attribute][3]. When specified, the element is required.

There is a lot of hand-wringing about how to define a `boolean` attribute. The HTML5 spec notes:

&gt;  The presence of a boolean attribute on an element represents the true value, and the absence of the attribute represents the false value.
&gt; 
&gt; If the attribute is present, its value must either be the empty string or a value that is an ASCII case-insensitive match for the attribute&#39;s canonical name, with no leading or trailing whitespace.

This means that you can specify a `required` **boolean** attribute two different ways:

    edName.attributes.required = &quot;&quot;; //the empty string
    edName.attributes.required = &quot;required&quot;; //the attribute&#39;s canonical name

But what is the value of the attribute *really*?
================

When you look at [my jsFiddle of this problem](http://jsfiddle.net/CP7sR/3/), you&#39;ll notice that if the `required` attribute is defined in the markup:

    &lt;input id=&quot;edName&quot; type=&quot;text&quot; id=&quot;name&quot; required&gt;

Then the attribute&#39;s value is ***not*** the empty string, nor the canonical name of the attribute:

    edName.attributes.required = [object Attr]

That might lead to a solution.


  [1]: http://i.stack.imgur.com/R3h1L.png
  [2]: http://www.w3.org/TR/html5/forms.html#attr-input-required
  [3]: http://www.w3.org/TR/html5/infrastructure.html#boolean-attribute

Content Type	Original Author	Original Content on Stackoverflow
Question	Wilker Iceri	View Question on Stackoverflow
Solution 1 - Javascript	t.niese	View Answer on Stackoverflow

Range out of order in character class in javascript

Javascript Problem Overview

Javascript Solutions

Solution 1 - Javascript

How to remove drawableleft

how to dynamically add options to an existing select in vanilla javascript

Attributions