C# method to do URL encoding? - c#

what c# class method can I use to URL encode a URL string?
In my use case I want to pass a URL string as a URL parameter itself. So like burying a URL within a URL. Without some encoding the "&" and "?" characters in the inner URL can get picked up when the parameters for the outer Url parameters are processed
thanks

HttpUtility.UrlEncode

System.Net.WebUtility.UrlEncode(str)

HttpServerUtility.UrlEncode might be exactly what you are looking for.

Use Server.UrlEncode
You need an instance of the HttpServerUtility class, because the UrlEncode method is not static.
See http://msdn.microsoft.com/en-us/library/system.web.httpserverutility(v=VS.90).aspx

I am operating with .net framework 2.0. But it never shows me "UrlEncode" intelisense when I place dot after httpserverutility. Here are the options I see:
HttpServerUtility.Equals
HttpServerUtility.ReferenceEquals
HttpServerUtility.UrlTokenDecode
HttpServerUtility.UrlTokenEncode
That's it, these are the only options I see. Could I possibly ask for small piece of code as an example to use url encode function?
Thanks,
Linda

Related

When ?id= string contains "&" symbol, Request.QueryString[id] doesn't return entire string

Does anyone know how to get the entire string?
Example:
var result = Request.QueryString[id];
returns "Jack" instead of "Jack & Jill" for the URL "http://website.com/test.html?=Jack&Jill
The problem is not in reading the parameter, but in constructing it. You have to change your link, or the code that creates the link.
You have to use URL escaping encoding:
http://website.com/test.html?=Jack%26Jill
URL encoding is supported in .NET (HttpUtility) and JS (global functions) as well.
& is a special character used to seperate paramaeters being passed. You need to encode your Url using ASP.NET provided functions.
Please use HttpServerUtility.UrlEncode() when assigning the url to id

Converting special characters to regular c#

Is there a command in C# to convert strings like : https%3A%2F%2Fwww.google.com back to https://www.google.com?
some sort of "decryption" method maybe?
You need to use System.Web.HttpUtility.UrlDecode for this:
string real = System.Web.HttpUtility.UrlDecode(encodedString);
You can use the reverse function System.Web.HttpUtility.UrlEncode to encode.
This is not a matter of encryption or decryption. It is just that some characters cannot be expressed as part of parameters or other in a URL. For instance, a colon (:) cannot be part of a URL tail because it is used in the prefix (http:), so it gets encoded as %3A.
In the same way, a slash gets encoded as %2F. Hence, %3A%2F2%F means ://.
You can use HttpUtility.UrlDecode
You can try
HttpUtility.UrlDecode(url);
or
Uri.UnescapeDataString(url);
If you're not working on a web application, I suggest you use the WebUtility class instead as you don't have to import the entire System.Web assembly to access UrlDecode, which is required for the HttpUtility class. (You'll need to be targeting .NET 4)
string unencoded = WebUtility.UrlDecode("https%3A%2F%2Fwww.google.com");
You can also use Uri.UnescapeDataString if don't require any other HTML encoding/decoding methods. This is System.Uri so you don't need to import any other assembly.

url encoding c# mismatch encoding

I have a large url that I am encoding using System.Web.HttpUtility.UrlEncode. When I encode it its not encoding it like the working example I have. I am not sure what the problem is, maybe different character type or something, I put an example of what suppose to be created and what actually being created. thanks for any help, i am lost on this one.
Working exmaple (look how this one has Did%252Citag%252 and the other doesnt)
22%7Chttp%3A%2F%2Fv17.nonxt1.googlevideo.com%2Fvideoplayback%3Fid%3D0b608733ae5257c3%26itag%3D22%26source%3Dpicasa%26ip%3D0.0.0.0%26ipbits%3D0%26expire%3D1333533157%26sparams%3Did%252Citag%252Csource%252Cip%252Cipbits%252Cexpire%26signature%3D8AD67D74F34FBAFBBA87616C0AED4A336DF0982A.129E2B5E648F8A2F35A34F312AC5C3C957A1C40A%26key%3Dlh1%2C35%7Chttp%3A%2F%2Fv18.nonxt3.googlevideo.com%2Fvideoplayback%3Fid%3D0b608733ae5257c3%26itag%3D35%26source%3Dpicasa%26ip%3D0.0.0.0%26ipbits%3D0%26expire%3D1333533157%26sparams%3Did%252Citag%252Csource%252Cip%252Cipbits%252Cexpire%26signature%3D7A58A11994C710872E945D0EAA6E43B6BFB8A648.B9C1D9FB377E1A49EBF3DC6C166C0B6E3E94EC24%26key%3Dlh1%2C34%7Chttp%3A%2F%2Fv6.nonxt1.googlevideo.com%2Fvideoplayback%3Fid%3D0b608733ae5257c3%26itag%3D34%26source%3Dpicasa%26ip%3D0.0.0.0%26ipbits%3D0%26expire%3D1333533157%26sparams%3Did%252Citag%252Csource%252Cip%252Cipbits%252Cexpire%26signature%3D260B10850A3448C849B8B8F1F2AF5E31244E71BC.6D7420FD66B85D40982BFB2C847EDB46021C63AE%26key%3Dlh1%2C5%7Chttp%3A%2F%2Fv23.nonxt7.googlevideo.com%2Fvideoplayback%3Fid%3D0b608733ae5257c3%26itag%3D5%26source%3Dpicasa%26ip%3D0.0.0.0%26ipbits%3D0%26expire%3D1333533157%26sparams%3Did%252Citag%252Csource%252Cip%252Cipbits%252Cexpire%26signature%3D9894DCDA7D2634EE0006CE0F6E0E29ABF7A8F253.18765D7CD7BDE80ED1A47DC8EC559C3E05C92F56%26key%3Dlh1
Here is an example of the one I am creating (see this one encodes as did%2citag%2)
5%7chttp%3a%2f%2fv23.nonxt7.googlevideo.com%2fvideoplayback%3fid%3d0b608733ae5257c3%26itag%3d5%26source%3dpicasa%26ip%3d0.0.0.0%26ipbits%3d0%26expire%3d1333562840%26sparams%3did%2citag%2csource%2cip%2cipbits%2cexpire%26signature%3dC0E2993011931D9F5FCAFAF54E821415F6042DDD.477CD23B021563A6DE30E858E35C21046E0B0BA6%26key%3dlh1%2c18%7chttp%3a%2f%2fv11.nonxt4.googlevideo.com%2fvideoplayback%3fid%3d0b608733ae5257c3%26itag%3d18%26source%3dpicasa%26ip%3d0.0.0.0%26ipbits%3d0%26expire%3d1333562840%26sparams%3did%2citag%2csource%2cip%2cipbits%2cexpire%26signature%3d696501A8ACBA0E1246173B040E0FB81DA8EBCDC7.944BA6C08C630EFFC2456D66BAD12376D7E377B2%26key%3dlh1%2c34%7chttp%3a%2f%2fv6.nonxt1.googlevideo.com%2fvideoplayback%3fid%3d0b608733ae5257c3%26itag%3d34%26source%3dpicasa%26ip%3d0.0.0.0%26ipbits%3d0%26expire%3d1333562840%26sparams%3did%2citag%2csource%2cip%2cipbits%2cexpire%26signature%3dDDD3D9081F7F2FF462D17CFAE6CAB72AEB86DEA9.3275E0EE8921EF728132035FC94BEF5926A0B7C1%26key%3dlh1%2c35%7chttp%3a%2f%2fv18.nonxt3.googlevideo.com%2fvideoplayback%3fid%3d0b608733ae5257c3%26itag%3d35%26source%3dpicasa%26ip%3d0.0.0.0%26ipbits%3d0%26expire%3d1333562840%26sparams%3did%2citag%2csource%2cip%2cipbits%2cexpire%26signature%3d7826E7470450F9F473BC7A845967EF3AC655CFB.3850F952F5D68151D325CD754C581CD66B0BC4D7%26key%3dlh1%2c22%7chttp%3a%2f%2fv17.nonxt1.googlevideo.com%2fvideoplayback%3fid%3d0b608733ae5257c3%26itag%3d22%26source%3dpicasa%26ip%3d0.0.0.0%26ipbits%3d0%26expire%3d1333562840%26sparams%3did%2citag%2csource%2cip%2cipbits%2cexpire%26signature%3d32FAAE6AE74B22BFB3DBD4300CEEDBC1A12A9ED4.8014678ABB1AEE93FB4B1C36E2C74C89102DC112%26key%3dlh1
Looks like in the first example the URL is double encoded. Meaning if you look at decoded sparams parameter it is represented as
sparams=id%2Citag%2Csource%2Cip%2Cipbits%2Cexpire
In your second example
sparams=id,itag,source,ip,ipbits,expire
So, what is happening in the first example is that, they are doing a UrlEncode on the value first. Using this value Construct the URL and then do UrlEncode on the constructed URL.
UPDATE : This is a general practice to be followed if the value of your querystring contains values which needs to be UrlEncoded (eg. , & space ? etc)
According to w3c standards, your example is fine. There is no %252 symbol.
I'm not sure exactly what you are expecting, but when you fire these strings into a URL Decoder, this is what you get:
String 1
22|http://v17.nonxt1.googlevideo.com/videoplayback?id=0b608733ae5257c3&itag=22&source=picasa&ip=0.0.0.0&ipbits=0&expire=1333533157&sparams=id%2Citag%2Csource%2Cip%2Cipbits%2Cexpire&signature=8AD67D74F34FBAFBBA87616C0AED4A336DF0982A.129E2B5E648F8A2F35A34F312AC5C3C957A1C40A&key=lh1,35|http://v18.nonxt3.googlevideo.com/videoplayback?id=0b608733ae5257c3&itag=35&source=picasa&ip=0.0.0.0&ipbits=0&expire=1333533157&sparams=id%2Citag%2Csource%2Cip%2Cipbits%2Cexpire&signature=7A58A11994C710872E945D0EAA6E43B6BFB8A648.B9C1D9FB377E1A49EBF3DC6C166C0B6E3E94EC24&key=lh1,34|http://v6.nonxt1.googlevideo.com/videoplayback?id=0b608733ae5257c3&itag=34&source=picasa&ip=0.0.0.0&ipbits=0&expire=1333533157&sparams=id%2Citag%2Csource%2Cip%2Cipbits%2Cexpire&signature=260B10850A3448C849B8B8F1F2AF5E31244E71BC.6D7420FD66B85D40982BFB2C847EDB46021C63AE&key=lh1,5|http://v23.nonxt7.googlevideo.com/videoplayback?id=0b608733ae5257c3&itag=5&source=picasa&ip=0.0.0.0&ipbits=0&expire=1333533157&sparams=id%2Citag%2Csource%2Cip%2Cipbits%2Cexpire&signature=9894DCDA7D2634EE0006CE0F6E0E29ABF7A8F253.18765D7CD7BDE80ED1A47DC8EC559C3E05C92F56&key=lh1
String 2
5|http://v23.nonxt7.googlevideo.com/videoplayback?id=0b608733ae5257c3&itag=5&source=picasa&ip=0.0.0.0&ipbits=0&expire=1333562840&sparams=id,itag,source,ip,ipbits,expire&signature=C0E2993011931D9F5FCAFAF54E821415F6042DDD.477CD23B021563A6DE30E858E35C21046E0B0BA6&key=lh1,18|http://v11.nonxt4.googlevideo.com/videoplayback?id=0b608733ae5257c3&itag=18&source=picasa&ip=0.0.0.0&ipbits=0&expire=1333562840&sparams=id,itag,source,ip,ipbits,expire&signature=696501A8ACBA0E1246173B040E0FB81DA8EBCDC7.944BA6C08C630EFFC2456D66BAD12376D7E377B2&key=lh1,34|http://v6.nonxt1.googlevideo.com/videoplayback?id=0b608733ae5257c3&itag=34&source=picasa&ip=0.0.0.0&ipbits=0&expire=1333562840&sparams=id,itag,source,ip,ipbits,expire&signature=DDD3D9081F7F2FF462D17CFAE6CAB72AEB86DEA9.3275E0EE8921EF728132035FC94BEF5926A0B7C1&key=lh1,35|http://v18.nonxt3.googlevideo.com/videoplayback?id=0b608733ae5257c3&itag=35&source=picasa&ip=0.0.0.0&ipbits=0&expire=1333562840&sparams=id,itag,source,ip,ipbits,expire&signature=7826E7470450F9F473BC7A845967EF3AC655CFB.3850F952F5D68151D325CD754C581CD66B0BC4D7&key=lh1,22|http://v17.nonxt1.googlevideo.com/videoplayback?id=0b608733ae5257c3&itag=22&source=picasa&ip=0.0.0.0&ipbits=0&expire=1333562840&sparams=id,itag,source,ip,ipbits,expire&signature=32FAAE6AE74B22BFB3DBD4300CEEDBC1A12A9ED4.8014678ABB1AEE93FB4B1C36E2C74C89102DC112&key=lh1
You URLS are quite different, and they also have a leading chars that I'm not sure you are wanting.

How to escape single quote in url query string with asp net

I am building the url in my web application and I am trying to pass a name as a query string, Bob O'Neal, which to my surprise does not seemed to be escaped properly with UrlEncode and there seems to be nothing on the net which talks about how to handle this?
Is there an elegant solution to properly handle escaping single quotes in query strings?
If you are storing the URL in a javascript statement to be executed on the client, then you need to do:
sURL = sURL.Replace("'", "\'");
You can use HttpUtility.UrlEncode, or its more secure counterpart, to encode the query string, but you shouldn't need to. Note that you will be able to retrieve it unencoded in the QueryString dictionary.
HttpUtility.UrlEncode("'"); //%27
There's a UrlPathEncode method as well, have you tried that one?
this user had a similar problem
UrlEncode encodes a single quote (') but not a slanted single quote(`)
If this is not the case in your 'error' (which it appears the OP of that topic claimed it was not) you will have to implement a UseMe function (see post) like described.

C# ASP.NET HttpWebRequest automatically decodes ampersand (&) values from query string?

Assume the following Url:
"http://server/application1/TestFile.aspx?Library=Testing&Filename=Documents & Functions + Properties.docx&Save=true"
I use HttpUtility.UrlEncode() to encode the value of the Filename parameter and I create the following Url:
"http://server/application1/TestFile.aspx?Library=Testing&Filename=Documents%20%26%20Functions%20%2B%20Properties.docx&Save=true"
I send the following (encoded version) of request from a client to a C# Web Application. On the server when I process the request I have a problem. The HttpRequest variable contains the query string partially decoded. That is to say when I try to use or quick watch the following properties of HttpRequest they have the following values.
Property = Value
================
HttpRequest.QueryString = "{Library=Testing&Filename=Documents+&+Functions+++Properties.docx&Save=true}"
HttpRequest.Url = "{http://server/application1/TestFile.aspx?Library=Testing&Filename=Documents & Functions + Properties.docx&Save=true}"
HttpRequest.Url.AbsoluteUri = "http://server/application1/TestFile.aspx?Library=Testing&Filename=Documents%20&%20Functions%20+%20Properties.docx&Save=true"
I have also checked the following properties but all of them have the & value decoded. However all other values remain properly encoded (e.g. space is %20).
HttpRequest.Url.OriginalString
HttpRequest.Url.Query
HttpRequest.Url.PathAndQuery
HttpRequest.RawUrl
There is no way I can read the value of the parameter Filename properly. Am I missing something?
The QueryString property returns a NameValueCollection object that maps the querystring keys to fully-decoded values.
You need to write Request.QueryString["FileName"].
I'm answering this question many years later because I just had this problem and figured out the solution. The problem is that HttpRequest.Url isn't really the value that you gave. HttpRequest.Url is a Uri class and that value is the ToString() value of that class. ToString() for the Uri class decodes the Url. Instead, what you want to use is HttpRequest.Url.OriginalString. That is the encoded version of the URL that you are looking for. Hope this helps some future person having this problem.
What happens when you don't use UrlEncode? You didn't show how exactly you are using the url that you created using UrlEncode, so it is quite possible that things are just being double encoded (lots of the framework will encode the URLs for you automatically).
FWIW I ran into this same problem with RavenDB (version 960). They implement their own HttpRequest object that behaves just like this -- it first decodes just the ampersands (from %26 to &) and then decodes the entire value. I believe this is a bug.
A couple of workarounds to this problem:
Implement your own query string parsing on the server. It's not fun but it is effective.
Double-encode ampersands. First encode just the ampersands in the string, then encode the entire string. (It's an easy solution but not extensible because it puts the burden on the client.)

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