`=C2=A0` represents the bytes C2 A0. Since this is UTF-8, it translates to U+00A0, which is the Unicode for non-breaking space.  

See *[UTF-8][1]* (Wikipedia).

  [1]: http://en.wikipedia.org/wiki/UTF-8


%C2%A0 This is the code of a hidden folder, create a hidden folder and save in it, for example, a text file, then open this file through a browser and you will see these characters in the search bar. As I understand it, these characters are optional and do not translate to other code.

I&#39;m writing the JS for a chat application I&#39;m working on in my free time, and I need to have HTML identifiers that change according to user submitted data. This is usually something conceptually shaky enough that I would not even attempt it, but I don&#39;t see myself having much of a choice this time. What I need to do then is to escape the HTML id to make sure it won&#39;t allow for XSS or breaking HTML.

Here&#39;s the code:

    var user_id = escape(id)
    var txt = &#39;&lt;div class=&quot;chut&quot;&gt;&#39;+
                &#39;&lt;div class=&quot;log&quot; id=&quot;chut_&#39;+user_id+&#39;&quot;&gt;&lt;/div&gt;&#39;+
                &#39;&lt;textarea id=&quot;chut_&#39;+user_id+&#39;_msg&quot;&gt;&lt;/textarea&gt;&#39;+
                &#39;&lt;label for=&quot;chut_&#39;+user_id+&#39;_to&quot;&gt;To:&lt;/label&gt;&#39;+
                &#39;&lt;input type=&quot;text&quot; id=&quot;chut_&#39;+user_id+&#39;_to&quot; value=&#39;+user_id+&#39; readonly=&quot;readonly&quot; /&gt;&#39;+
                &#39;&lt;input type=&quot;submit&quot; id=&quot;chut_&#39;+user_id+&#39;_send&quot; value=&quot;Message&quot;/&gt;&#39;+
              &#39;&lt;/div&gt;&#39;;

What would be the best way to escape `id` to avoid any kind of problem mentioned above? As you can see, right now I&#39;m using the built-in `escape()` function, but I&#39;m not sure of how good this is supposed to be compared to other alternatives. I&#39;m mostly used to sanitizing input before it goes in a text node, not an id itself.

Sanitizing user input before adding it to the DOM in Javascript

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This is an example raw email I am trying to parse:

    MIME-version: 1.0
    Content-type: text/html; charset=UTF-8
    Content-transfer-encoding: quoted-printable
    X-Mailer: Verizon Webmail
    X-Originating-IP: [x.x.x.x]
    
    =C2=A0test testing testing 123

What is =C2=A0?  I have tried a half dozen quoted-printable parsers, but none handle this correctly.  **How would one properly parse this in C#?**

Honestly, for now, I&#39;m coding:

    //TODO WTF
    encoded = encoded.Replace(&quot;=C2=A0&quot;, &quot;&quot;);

Because I can&#39;t figure out why that text is there randomly within the MIME content, and isn&#39;t supposed to be rendered into anything.  By just removing it, I&#39;m getting the desired effect - but WHY?!

To be clear, I know that (=[0-9A-F]{2}) is an encoded character.  But in this case, it seemingly represents NOTHING.

What is &quot;=C2=A0&quot; in MIME encoded, quoted-printable text?

This is an example raw email I am trying to parse:
<pre><code class="hljs language-makefile">MIME-version: 1.0
Content-type: text/html; charset=UTF-8
Content-transfer-encoding: quoted-printable
X-Mailer: Verizon Webmail
X-Originating-IP: [x.x.x.x]

=C2=A0test testing testing 123
</code></pre>
What is =C2=A0? I have tried a half dozen quoted-printable parsers, but none handle this correctly. How would one properly parse this in C#?
Honestly, for now, I'm coding:
<pre><code class="hljs language-ini">//TODO WTF
encoded = encoded.Replace("=C2=A0", "");
</code></pre>
Because I can't figure out why that text is there randomly within the MIME content, and isn't supposed to be rendered into anything. By just removing it, I'm getting the desired effect - but WHY?!
To be clear, I know that (=[0-9A-F]{2}) is an encoded character. But in this case, it seemingly represents NOTHING.

I&#39;m trying to pass the output of a SQL Server exception to the client using the `RegisterStartUpScript` method of the MS ScriptManager in .NET 3.5. This works fine for some errors but when the exception contains single quotes the alert fails.

I dont want to only escape single quotes though. Is there a standard function I can call to escape any special chars for use in JavaScript?

    string scriptstring = &quot;alert(&#39;&quot; + ex.Message + &quot;&#39;);&quot;;         
    ScriptManager.RegisterStartupScript(this, this.GetType(), &quot;Alert&quot;, scriptstring , true);

----------
**EDIT**:

Thanks @tpeczek, the code *almost* worked for me :) but with a slight amendment (the escaping of single quotes) it works a treat.

I&#39;ve included my amended version here...

    public class JSEncode
    {
        /// &lt;summary&gt;
        /// Encodes a string to be represented as a string literal. The format
        /// is essentially a JSON string.
        /// 
        /// The string returned includes outer quotes 
        /// Example Output: &quot;Hello \&quot;Rick\&quot;!\r\nRock on&quot;
        /// &lt;/summary&gt;
        /// &lt;param name=&quot;s&quot;&gt;&lt;/param&gt;
        /// &lt;returns&gt;&lt;/returns&gt;
        public static string EncodeJsString(string s)
        {
            StringBuilder sb = new StringBuilder();
            sb.Append(&quot;\&quot;&quot;);
            foreach (char c in s)
            {
                switch (c)
                {
                    case &#39;\&#39;&#39;:
                        sb.Append(&quot;\\\&#39;&quot;);
                        break;
                    case &#39;\&quot;&#39;:
                        sb.Append(&quot;\\\&quot;&quot;);
                        break;
                    case &#39;\\&#39;:
                        sb.Append(&quot;\\\\&quot;);
                        break;
                    case &#39;\b&#39;:
                        sb.Append(&quot;\\b&quot;);
                        break;
                    case &#39;\f&#39;:
                        sb.Append(&quot;\\f&quot;);
                        break;
                    case &#39;\n&#39;:
                        sb.Append(&quot;\\n&quot;);
                        break;
                    case &#39;\r&#39;:
                        sb.Append(&quot;\\r&quot;);
                        break;
                    case &#39;\t&#39;:
                        sb.Append(&quot;\\t&quot;);
                        break;
                    default:
                        int i = (int)c;
                        if (i &lt; 32 || i &gt; 127)
                        {
                            sb.AppendFormat(&quot;\\u{0:X04}&quot;, i);
                        }
                        else
                        {
                            sb.Append(c);
                        }
                        break;
                }
            }
            sb.Append(&quot;\&quot;&quot;);
    
            return sb.ToString();
        }
    }

As mentioned below - original source: [here][1]

  [1]: http://www.west-wind.com/weblog/posts/114530.aspx

Is there a standard way to encode a .NET string into JavaScript string for use in MS Ajax?

I&#39;m writing a crawler in Ruby (1.9) that consumes lots of HTML from a lot of random sites.  
When trying to extract links, I decided to just use `.scan(/href=&quot;(.*?)&quot;/i)` instead of nokogiri/hpricot (major speedup). The problem is that I now receive a lot of &quot;`invalid byte sequence in UTF-8`&quot; errors.  
From what I understood, the `net/http` library doesn&#39;t have any encoding specific options and the stuff that comes in is basically not properly tagged.  
What would be the best way to actually work with that incoming data? I tried `.encode` with the replace and invalid options set, but no success so far...

ruby 1.9: invalid byte sequence in UTF-8

When I run `maven install` on my multi module maven project I always get the following output:

    [WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!

So, I googled around a bit, but all I can find is that I have to add:

    &lt;properties&gt;
        &lt;project.build.sourceEncoding&gt;UTF-8&lt;/project.build.sourceEncoding&gt;
    &lt;/properties&gt;

...to my pom.xml. But it&#39;s already there (in the parent `pom.xml`).

Configuring `&lt;encoding&gt;` for the maven-resources-plugin or the maven-compiler-plugin also doesn&#39;t fix it. 

So what&#39;s the problem?

How to configure encoding in Maven?

I&#39;m still learning python and I have a doubt:

In python 2.6.x I usually declare encoding in the file header like this (as in [PEP 0263][1])

    # -*- coding: utf-8 -*-

After that, my strings are written as usual:

    a = &quot;A normal string without declared Unicode&quot;

But everytime I see a python project code, the encoding is not declared at the header. Instead, it is declared at every string like this:

    a = u&quot;A string with declared Unicode&quot;

What&#39;s the difference? What&#39;s the purpose of this? I know Python 2.6.x sets ASCII encoding by default, but it can be overriden by the header declaration, so what&#39;s the point of per string declaration?

**Addendum:** Seems that I&#39;ve mixed up file encoding with string encoding. Thanks for explaining it :)

  [1]: http://www.python.org/dev/peps/pep-0263/

Why declare unicode by string in python?

I am searching for a short and cool rot13 function in Python ;-)
I&#39;ve written this function:

    def rot13(s):
        chars = &quot;abcdefghijklmnopqrstuvwxyz&quot;
        trans = chars[13:]+chars[:13]
        rot_char = lambda c: trans[chars.find(c)] if chars.find(c)&gt;-1 else c
        return &#39;&#39;.join( rot_char(c) for c in s ) 

Can anyone make it better? E.g supporting uppercase characters.

Short rot13 function - Python

Searching the web, I find heaps of different suggestions for what the proper MIME type for a font is, but I have yet to try any MIME type that rids me of a Chrome warning such as the following:

&gt; Resource interpreted as font but transferred with MIME type font/otf

The font is an OTF.

I&#39;ve tried the following MIME types so far

* font/otf
* application/font-otf
* application/font
* application/otf
* application/octet-stream
* application/x-font-otf
* application/x-font-TrueType (I know it&#39;s not truetype, but one source quoted this for OTF)

Proper MIME type for OTF fonts

Just ran my site in chrome and suprisingly it comes up with this warning for each of my .png images:

    Resource interpreted as image but transferred with MIME type application/octet-stream.

Anyone seen this before?

Regards

MIME type warning in chrome for png images

When creating [email messages][1] you are supposed to set the [Content-Type][2] to `multipart/alternative` when sending HTML and TEXT or `multipart/mixed` when sending TEXT and attachments.

So what do you do if you want to send HTML, Text, and attachments? Use both?


  [1]: http://www.w3.org/Protocols/rfc1341/7_2_Multipart.html
  [2]: http://en.wikipedia.org/wiki/MIME#Content-Type

Mail multipart/alternative vs multipart/mixed

My PHP script sends email to users and when the email arrives to their mailboxes, the subject line (`$subject`) has characters like `a^&#163;` added to the end of my subject text. This is obviously and encoding problem. The email message content itself is fine, just the subject line is broken.

I have searched all over but can’t find **how to encode my subject properly**.

This is my header. Notice that I’m using `Content-Type` with `charset=utf-8` and  `Content-Transfer-Encoding: 8bit`.

    //set all necessary headers
    $headers = &quot;From: $sender_name&lt;$from&gt;\n&quot;;
    $headers .= &quot;Reply-To: $sender_name&lt;$from&gt;\n&quot;;
    $headers .= &quot;X-Sender: $sender_name&lt;$from&gt;\n&quot;;
    $headers .= &quot;X-Mailer: PHP4\n&quot;; //mailer
    $headers .= &quot;X-Priority: 3\n&quot;; //1 UrgentMessage, 3 Normal
    $headers .= &quot;MIME-Version: 1.0\n&quot;;
    $headers .= &quot;X-MSMail-Priority: High\n&quot;;
    $headers .= &quot;Importance: 3\n&quot;;
    $headers .= &quot;Date: $date\n&quot;;
    $headers .= &quot;Delivered-to: $to\n&quot;;
    $headers .= &quot;Return-Path: $sender_name&lt;$from&gt;\n&quot;;
    $headers .= &quot;Envelope-from: $sender_name&lt;$from&gt;\n&quot;;
    $headers .= &quot;Content-Transfer-Encoding: 8bit\n&quot;;
    $headers .= &quot;Content-Type: text/plain; charset=UTF-8\n&quot;;

Email from PHP has broken Subject header encoding

I&#39;m trying to send a multipart/related html email with embedded gif images.  This email is generated using Oracle PL/SQL.  My attempts have failed, with the image showing up as a red X (in Outlook 2007 and yahoo mail)

I&#39;ve been sending html emails for some time, but my requirements are now to use several gif images in the email.  I can store these on one of our web servers and just link to them, but many users email clients will not show them automatically and will need to either change settings or manually download them for each email.

So, my thoughts are to embed the image.  My questions are:

1.  What am I doing wrong here?
2.  Is the embedding approach the correct one?
3.  Any other options if I need to use more and more images?  Attachments won&#39;t work, as the images are typically logos and icons that won&#39;t make sense out of the context of the message.  Also, some elements of the email are links into an online system, so generating a static PDF and attaching won&#39;t work (to my knowledge anyway).
 
snippet:

    MIME-Version: 1.0
    To: me@gmail.com
    BCC: me@yahoo.com
    From: email@yahoo.com
    Subject: Test
    Reply-To: email@yahoo.com
    Content-Type: multipart/related; boundary=&quot;a1b2c3d4e3f2g1&quot;
    
    --a1b2c3d4e3f2g1
    
    content-type: text/html;
    
        &lt;html&gt;
        &lt;head&gt;&lt;title&gt;My title&lt;/title&gt;&lt;/head&gt;
        &lt;body&gt;
        &lt;div style=&quot;font-size:11pt;font-family:Calibri;&quot;&gt;
        &lt;p&gt;&lt;IMG SRC=&quot;cid:my_logo&quot; alt=&quot;Logo&quot;&gt;&lt;/p&gt;
    
    ... more html here ...
    
    &lt;/div&gt;&lt;/body&gt;&lt;/html&gt; 
    
    --a1b2c3d4e3f2g1
    
    Content-Type: image/gif;
    Content-ID:&lt;my_logo&gt;
    Content-Transfer-Encoding: base64
    Content-Disposition: inline
    
    [base64 image data here]
    
    --a1b2c3d4e3f2g1--



Many thanks.

BTW: Yes, I have verified that the base64 data is correct, as I can embed the image in the html itself (using same algo use for creating header data) and see image in Firefox/IE.

I should also note that this is NOT for spam, the emails are sent to specific clients who are expecting it daily.  The content is data-driven, and not adverts.

Content Type	Original Author	Original Content on Stackoverflow
Question	TheSoftwareJedi	View Question on Stackoverflow
Solution 1 - Encoding	Steven Sudit	View Answer on Stackoverflow
Solution 2 - Encoding	Yi Yang	View Answer on Stackoverflow
Solution 3 - Encoding	Ygor	View Answer on Stackoverflow

What is "=C2=A0" in MIME encoded, quoted-printable text?

Encoding Problem Overview

Encoding Solutions

Solution 1 - Encoding

Solution 2 - Encoding

Solution 3 - Encoding

VB.NET: how to prevent user input in a ComboBox

Sanitizing user input before adding it to the DOM in Javascript

Attributions