You have to use [Convert.FromBase64String][1] to turn a **Base64** encoded `string` into a `byte[]`.


  [1]: http://msdn.microsoft.com/en-us/library/system.convert.frombase64string.aspx

This may be helpful

    byte[] bytes = System.Convert.FromBase64String(stringInBase64);



Try 

    byte[] incomingByteArray = receive...; // This is your Base64-encoded bute[]

    byte[] decodedByteArray =Convert.FromBase64String (Encoding.ASCII.GetString (incomingByteArray)); 
    // This work because all Base64-encoding is done with pure ASCII characters


You&#39;re looking for the `FromBase64Transform` class, used with the `CryptoStream` class.

If you have a string, you can also call `Convert.FromBase64String`.

I&#39;ve written an extension method for this purpose:

	public static byte[] FromBase64Bytes(this byte[] base64Bytes)
	{
		string base64String = Encoding.UTF8.GetString(base64Bytes, 0, base64Bytes.Length);
		return Convert.FromBase64String(base64String);
	}

Call it like this:

	byte[] base64Bytes = .......
	byte[] regularBytes = base64Bytes.FromBase64Bytes();

I hope it helps someone.

I&#39;m writing StoreKit-related code, and I&#39;m getting some rather troubling error codes when I try to add a purchase to the queue.

So far, I&#39;ve experienced error codes -1003 and -1004 and I can&#39;t find anything about those codes on the internet.

Running a product request returns valid product numbers, so I don&#39;t know why calls to `[[SKPaymentQueue defaultQueue] addPayment:aPayment];` would fail with this undocumented problem.

The same code also works without the errors on one device but not on another.

The questions I have are, as of yet, unanswered:

What do these codes mean?
How can I mitigate this problem?
Why are they happening for purchase attempts and not for product requests?

Troubleshooting I&#39;ve done includes regenerating a signing certificate and provisioning profile, changing WiFi networks, cleaning and building and reinstalling all related software and components, and none of these things individually or together have helped fix the problem.

EDIT:

Found a discussion about this on the Apple dev forums, but no one from Apple has responded: https://devforums.apple.com/thread/107121?tstart=75 (iOS developer account required to view)

EDIT:

I was hit with error code -1001 today, to add to this list of inexplicable and intermittent problems.  Still no accountability from Apple, that I can find.

EDIT:

I have a suspicion that these error codes are randomly generated and really only indicate that the Sandbox is down.  Anyone else experience this problem?

Undocumented NSURLErrorDomain error codes (-1001, -1003 and -1004) using StoreKit

I have some bells in my database with the same number. I want to get all of them without duplication. I created a compare class to do this work, but the execution of the function causes a big delay from the function without distinct, from 0.6 sec to 3.2 sec!

Am I doing it right or do I have to use another method?

    reg.AddRange(
        (from a in this.dataContext.reglements
         join b in this.dataContext.Clients on a.Id_client equals b.Id
         where a.date_v &lt;= datefin &amp;&amp; a.date_v &gt;= datedeb
         where a.Id_client == b.Id
         orderby a.date_v descending 
         select new Class_reglement
         {
             nom  = b.Nom,
             code = b.code,
             Numf = a.Numf,
         })
        .AsEnumerable()
        .Distinct(new Compare())
        .ToList());

    class Compare : IEqualityComparer&lt;Class_reglement&gt;
    {
        public bool Equals(Class_reglement x, Class_reglement y)
        {
            if (x.Numf == y.Numf)
            {
                return true;
            }
            else { return false; }
        }
        public int GetHashCode(Class_reglement codeh)
        {
            return 0;
        }
    }



How to use the IEqualityComparer

I have a  `Base64 byte[]` array which is transferred from a stream which i need to convert it to a normal `byte[]` how to do this ?

C# Convert a Base64 -&gt; byte[]

<p>I have a  <code>Base64 byte[]</code> array which is transferred from a stream which i need to convert it to a normal <code>byte[]</code> how to do this ?</p>


I&#39;m running into a behavior I wasn&#39;t expecting when using Enum.TryParse.

If I have an enum:

    public enum MyEnum
    {
      ValueA,
      ValueB,
      ValueC
    }

And then I pass a numeric value (as a string) into Enum.TryParse, like:

    MyEnum outputEnum;
    bool result = Enum.TryParse(&quot;1234&quot;, out outputEnum);

Despite the string &quot;1234&quot; not being a possible value, result will come back as true, and my outputEnum will have a value of 1234. 

Is there a way I can avoid this sort of behavior? I&#39;m trying to write a function which will process arbitrary string input as an enum, and this has thrown a bit of a monkeywrench in my bad-input detection.

Enum.TryParse returns true for any numeric values

Given that strings are immutable in .NET, I&#39;m wondering why they have been designed such that `string.Substring()` takes O(`substring.Length`) time, instead of `O(1)`?

i.e. what were the tradeoffs, if any?

If strings are immutable in .NET, then why does Substring take O(n) time?

How can I convert an int to a bit array?

If I e.g. have an int with the value 3 I want an array, that has the length 8 and that looks like this:

    0 0 0 0 0 0 1 1

Each of these numbers are in a separate slot in the array that have the size 8.

Convert int to a bit array in .NET

What is the proper way to get the complete name of month of a `DateTime` object?  
e.g. `January`, `December`. 

I am currently using: 

    DateTime.Now.ToString(&quot;MMMMMMMMMMMMM&quot;);

I know it&#39;s not the correct way to do it.

How to get complete month name from DateTime

    @* Omitted code.. *@
    @RenderBody()
    @RenderSection(&quot;Sidebar&quot;, required: false)

Is there any way to know in the `Omitted code` part if the RenderSection `Sidebar` exists or not?


How can I know if a non-required RenderSection exists?

I know what `base64` encoding is and how to calculate `base64` encoding in C#, however I have seen several times that when I convert a string into base64, there is an `=` at the end.

A few questions came up:

 1. Does a `base64` string always end with `=`?
 2. Why does an `=` get appended at the end?

Why does a base64 encoded string have an = sign at the end

My Express app is receiving a base64-encoded PNG from the browser (generated from canvas with toDataURL() ) and writing it to a file. But the file isn&#39;t a valid image file, and the &quot;file&quot; utility simply identifies it as &quot;data&quot;.

    var body = req.rawBody,
      base64Data = body.replace(/^data:image\/png;base64,/,&quot;&quot;),
      binaryData = new Buffer(base64Data, &#39;base64&#39;).toString(&#39;binary&#39;);
    
    require(&quot;fs&quot;).writeFile(&quot;out.png&quot;, binaryData, &quot;binary&quot;, function(err) {
      console.log(err); // writes out file without error, but it&#39;s not a valid image
    });

How can I save a base64-encoded image to disk?

I&#39;ve got a basic HTML form from which I can grab a bit of information that I&#39;m examining in Firebug.

My only issues is that I&#39;m trying to ***base64*** encode the file data before it&#39;s sent to the server where it&#39;s required to be in that form to be saved to the database.

    &lt;input type=&quot;file&quot; id=&quot;fileupload&quot; /&gt;

And in Javascript+jQuery:

    var file = $(&#39;#fileupload&#39;).attr(&quot;files&quot;)[0];

I have some operations based on available javascript: *.getAsBinary(), .getAsText(), .getAsTextURL*

However none of these return usable text that can be inserted as they contain *unusable &#39;characters&#39;* - I don&#39;t want to have a &#39;postback&#39; occur in my file uploaded, and I need to have multiple forms targeting specific objects so it&#39;s important I get the file and use Javascript this way.

How should I get the file in such a way that I can use one of the Javascript base64 encoders that are widely available!? 

Thanks
----------

## Update - Starting bounty here, need cross-browser support!!! ##

*Here is where I&#39;m at:* 

    &lt;input type=&quot;file&quot; id=&quot;fileuploadform&quot; /&gt;
    
    &lt;script type=&quot;text/javascript&quot;&gt;
    var uploadformid = &#39;fileuploadform&#39;;
    var uploadform = document.getElementById(uploadformid);


    /* method to fetch and encode specific file here based on different browsers */
    
    &lt;/script&gt;

Couple of issues with cross browser support:

    var file = $j(fileUpload.toString()).attr(&#39;files&#39;)[0];
    fileBody = file.getAsDataURL(); // only would works in Firefox

Also, IE doesn&#39;t support:

    var file = $j(fileUpload.toString()).attr(&#39;files&#39;)[0];

So I have to replace with:

    var element = &#39;id&#39;;
    var element = document.getElementById(id);

For IE Support.
			
This works in Firefox, Chrome and, Safari (but doesn&#39;t properly encode the file, or at least after it&#39;s been posted the file doesn&#39;t come out right)		
    
    var file = $j(fileUpload.toString()).attr(&#39;files&#39;)[0];
    var encoded = Btoa(file);

Also,

    file.readAsArrayBuffer() 

Seems to be only supported in HTML5?

***Lots of people suggested:*** [http://www.webtoolkit.info/javascript-base64.html][1]

But this only returns an error on the UTF_8 method before it base64 encodes? (or an empty string)

    var encoded = Base64.encode(file); 

  [1]: http://www.webtoolkit.info/javascript-base64.html

Get Base64 encode file-data from Input Form

I&#39;m trying to quickly encode a simple ASCII string to base64 (Basic HTTP Authentication using boost::asio) and not paste in any new code code or use any libraries beyond boost.

Simple signature would look like:
**string Base64Encode(const string&amp; text);**

Again I realize the algorithm is easy and there are many libraries/examples doing this but I&#39;m looking for a clean boost example.  I found boost serialization but no clear examples there or from Google.
http://www.boost.org/doc/libs/1_46_1/libs/serialization/doc/dataflow.html

Is this possible without adding the actual base64 algorithm explicitly to my code?

How do I encode a string to base64 using only boost?

I am trying to &quot;decode&quot; this following Base64 string:

&gt; OBFZDTcPCxlCKhdXCQ0kMQhKPh9uIgYIAQxALBtZAwUeOzcdcUEeW0dMO1kbPElWCV1ISFFKZ0kdWFlLAURPZhEFQVseXVtPOUUICVhMAzcfZ14AVEdIVVgfAUIBWVpOUlAeaUVMXFlKIy9rGUN0VF08Oz1POxFfTCcVFw1LMQNbBQYWAQ==

This is what I know about the string itself:

1. The original string is first passed through the following code:

        private static string m000493(string p0, string p1)
        {
            StringBuilder builder = new StringBuilder(p0);
            StringBuilder builder2 = new StringBuilder(p1);
            StringBuilder builder3 = new StringBuilder(p0.Length);
            int num = 0;
        Label_0084:
            while (num &lt; builder.Length)
            {
                int num2 = 0;
                while (num2 &lt; p1.Length)
                {
                    if ((num == builder.Length) || (num2 == builder2.Length))
                    {
                        MessageBox.Show(&quot;EH?&quot;);
                        goto Label_0084;
                    }
                    char ch = builder[num];
                    char ch2 = builder2[num2];
                    ch = (char)(ch ^ ch2);
                    builder3.Append(ch);
                    num2++;
                    num++;
                }
            }
            return m0001cd(builder3.ToString());
        }
The `p1` part in the code is supposed to be the string &quot;`_p0lizei.`&quot;.

2. It is then converted to a Base64 string by the following code:

        private static string m0001cd(string p0)
        {
            string str2;
            try
            {
                byte[] buffer = new byte[p0.Length];
                str2 = Convert.ToBase64String(Encoding.UTF8.GetBytes(p0));
            }
            catch (Exception exception)
            {
                throw new Exception(&quot;Error in base64Encode&quot; + exception.Message);
            }
            return str2;
        }

The question is, how do I decode the Base64 string so that I can find out what the original string is?

Content Type	Original Author	Original Content on Stackoverflow
Question	Sudantha	View Question on Stackoverflow
Solution 1 - C#	Zruty	View Answer on Stackoverflow
Solution 2 - C#	Selim Reza	View Answer on Stackoverflow
Solution 3 - C#	Yahia	View Answer on Stackoverflow
Solution 4 - C#	SLaks	View Answer on Stackoverflow
Solution 5 - C#	Duco	View Answer on Stackoverflow

C# Convert a Base64 -> byte[]

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

Solution 3 - C#

Solution 4 - C#

Solution 5 - C#

How to use the IEqualityComparer

Undocumented NSURLErrorDomain error codes (-1001, -1003 and -1004) using StoreKit

Attributions