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How to split a url c# [duplicate]

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Get URL parameters from a string in .NET
(17 answers)
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I have a uri string like: http://example.com/file?a=1&b=2&c=string%20param
Is there an existing function that would convert query parameter string into a dictionary same way as ASP.NET Context.Request does it.
I'm writing a console app and not a web-service so there is no Context.Request to parse the URL for me.
I know that it's pretty easy to crack the query string myself but I'd rather use a FCL function is if exists.

Use this:
string uri = ...;
string queryString = new System.Uri(uri).Query;
var queryDictionary = System.Web.HttpUtility.ParseQueryString(queryString);
This code by Tejs isn't the 'proper' way to get the query string from the URI:
string.Join(string.Empty, uri.Split('?').Skip(1));

You can use:
var queryString = url.Substring(url.IndexOf('?')).Split('#')[0]
System.Web.HttpUtility.ParseQueryString(queryString)
MSDN

This should work:
string url = "http://example.com/file?a=1&b=2&c=string%20param";
string querystring = url.Substring(url.IndexOf('?'));
System.Collections.Specialized.NameValueCollection parameters =
System.Web.HttpUtility.ParseQueryString(querystring);
According to MSDN. Not the exact collectiontype you are looking for, but nevertheless useful.
Edit: Apparently, if you supply the complete url to ParseQueryString it will add 'http://example.com/file?a' as the first key of the collection. Since that is probably not what you want, I added the substring to get only the relevant part of the url.

I had to do this for a modern windows app. I used the following:
public static class UriExtensions
{
private static readonly Regex _regex = new Regex(#"[?&](\w[\w.]*)=([^?&]+)");
public static IReadOnlyDictionary<string, string> ParseQueryString(this Uri uri)
{
var match = _regex.Match(uri.PathAndQuery);
var paramaters = new Dictionary<string, string>();
while (match.Success)
{
paramaters.Add(match.Groups[1].Value, match.Groups[2].Value);
match = match.NextMatch();
}
return paramaters;
}
}

Have a look at HttpUtility.ParseQueryString() It'll give you a NameValueCollection instead of a dictionary, but should still do what you need.
The other option is to use string.Split().
string url = #"http://example.com/file?a=1&b=2&c=string%20param";
string[] parts = url.Split(new char[] {'?','&'});
///parts[0] now contains http://example.com/file
///parts[1] = "a=1"
///parts[2] = "b=2"
///parts[3] = "c=string%20param"

For isolated projects, where dependencies must be kept to a minimum, I found myself using this implementation:
var arguments = uri.Query
.Substring(1) // Remove '?'
.Split('&')
.Select(q => q.Split('='))
.ToDictionary(q => q.FirstOrDefault(), q => q.Skip(1).FirstOrDefault());
Do note, however, that I do not handle encoded strings of any kind, as I was using this in a controlled setting, where encoding issues would be a coding error on the server side that should be fixed.

In a single line of code:
string xyz = Uri.UnescapeDataString(HttpUtility.ParseQueryString(Request.QueryString.ToString()).Get("XYZ"));

Microsoft Azure offers a framework that makes it easy to perform this.
http://azure.github.io/azure-mobile-services/iOS/v2/Classes/MSTable.html#//api/name/readWithQueryString:completion:

You could reference System.Web in your console application and then look for the Utility functions that split the URL parameters.

HttpUtility.UrlEncode unexpected output

Iam trying to encode a url, so that the HttpWebRequest is fine with characters like &.
So google bring me up to this:
url = HttpUtility.UrlEncode(url);
But this makes the whole url unuseable. Iam getting Status-Error: Invalid Operation from Web-Server.
I got this url before iam using encoding:
http://jira-test.myServer.de/rest/api/2/search?jql=labels = "F&E"
After encoding i got this:
http%3a%2f%2fjira-test.brillux.de%2frest%2fapi%2f2%2fsearch%3fjql%3dlabels+%3d+%22F%26E%22
What iam doing wrong? In my opinion it shouldn't replace the // after http and so on... Or is there another way to handle this issue?
Info:
Uri.EscapeDataString();
gives me the same result.

You should only be encoding the values of your query string, not the entire URI:
var uri = "http://jira-test.myServer.de/rest/api/2/search?jql=" +
HttpUtility.UrlEncode("labels = \"F&E\"");
// Result: http://jira-test.myServer.de/rest/api/2/search?jql=labels+%3d+%22F%26E%22
The proper way to construct this:
// Construct query string using HttpValueCollection, which handles escaping:
var queryString = HttpUtility.ParseQueryString(string.Empty);
queryString.Add("jql", "labels = \"F&E\"");
// Combine base URI with query string through UriBuilder:
var uriBuilder = new UriBuilder("http://jira-test.myServer.de/rest/api/2/search");
uriBuilder.Query = queryString.ToString();
// Get string representation:
string uri = uriBuilder.ToString();
// Result: http://jira-test.myserver.de:80/rest/api/2/search?jql=labels+%3d+%22F%26E%22

how to get substring or part of string from a url in c#

I have an application where uses post comments. Security is not an issue.
string url = http://example.com/xyz/xyz.html?userid=xyz&comment=Comment
What i want is to extract the userid and comment from above string.
I tried and found that i can use IndexOf and Substring to get the desired code BUT what if the userid or comment also has = symbol and & symbol then my IndexOf will return number and my Substring will be wrong.
Can you please find me a more suitable way of extracting userid and comment.
Thanks.

I got url using string url =
HttpContext.Current.Request.Url.AbsoluteUri;
Do not use AbsoluteUri property , it will give you a string Uri, instead use the Url property directly like:
var result = System.Web.HttpUtility.ParseQueryString(HttpContext.Current.Request.Url.Query);
and then you can extract each parameter like:
Console.WriteLine(result["userid"]);
Console.WriteLine(result["comment"]);
For other cases when you have string uri then do not use string operations, instead use Uri class.
Uri uri = new Uri(#"http://example.com/xyz/xyz.html?userid=xyz&comment=Comment");
You can also use TryCreate method which doesn't throw exception in case of invalid Uri.
Uri uri;
if (!Uri.TryCreate(#"http://example.com/xyz/xyz.html?userid=xyz&comment=Comment", UriKind.RelativeOrAbsolute, out uri))
{
//Invalid Uri
}
and then you can use System.Web.HttpUtility.ParseQueryString to get query string parameters:
var result = System.Web.HttpUtility.ParseQueryString(uri.Query);

The ugliest way is the following:
String url = "http://example.com/xyz/xyz.html?userid=xyz&comment=Comment";
usr = url.Split('?')[1];
usr= usr.Split('&')[0];
usr = usr.Split('=')[1];
But #habib version is better

Replace URL in a string

I'm a beginner in C# and I have the following string,
string url = "svn1/dev";
along with,
string urlMod = "ato-svn3-sslv3.of.lan/svn/dev"
I want to replace svn1 in url with "ato-svn3-sslv3.of.lan"

Although your question still has some inconsistent statements, I believe String.Replace is what you are looking for:
http://msdn.microsoft.com/en-us/library/fk49wtc1.aspx
url = url.Replace("svn1","ato-svn3-sslv3.of.lan");

Strings are immutable so you need to assign the return value to a variable:
string replacement = "ato-svn3-sslv3.of.lan";
url = url.Replace("svn1", replacement);

You can use the string method replace.
url = url.Replace("svn1", urlMod)

I think you need this:
string url = "svn1/dev";
string anotherUrl = "ato-svn3-sslv3.of.lan/svn/dev";
string toBeReplaced = anotherUrl.Split('/')[0];
url = url.Replace("svn1", toBeReplaced);
It uses split method and replace method.

How can I parse HTTP urls in C#?

My requirement is to parse Http Urls and call functions accordingly. In my current implementation, I am using nested if-else statement which i think is not an optimized way. Can you suggest some other efficient approch?
Urls are like these:
server/func1
server/func1/SubFunc1
server/func1/SubFunc2
server/func2/SubFunc1
server/func2/SubFunc2

I think you can get a lot of use out of the System.Uri class. Feed it a URI and you can pull out pieces in a number of arrangements.
Some examples:
Uri myUri = new Uri("http://server:8080/func2/SubFunc2?query=somevalue");
// Get host part (host name or address and port). Returns "server:8080".
string hostpart = myUri.Authority;
// Get path and query string parts. Returns "/func2/SubFunc2?query=somevalue".
string pathpart = myUri.PathAndQuery;
// Get path components. Trailing separators. Returns { "/", "func2/", "sunFunc2" }.
string[] pathsegments = myUri.Segments;
// Get query string. Returns "?query=somevalue".
string querystring = myUri.Query;

This might come as a bit of a late answer but I found myself recently trying to parse some URLs and I went along using a combination of Uri and System.Web.HttpUtility as seen here, my URLs were like http://one-domain.com/some/segments/{param1}?param2=x.... so this is what I did:
var uri = new Uri(myUrl);
string param1 = uri.Segments.Last();
var parameters = HttpUtility.ParseQueryString(uri.Query);
string param2 = parameters["param2"];
note that in both cases you'll be working with strings, and be specially weary when working with segments.

I combined the split in Suncat2000's answer with string splitting to get at interesting features of the URL. I am passing in a full Uri including https: etc. from another page as the navigation argument e.Parameter:
Uri playlistUri = (Uri)e.Parameter;
string youtubePlaylistUnParsed = playlistUri.Query;
char delimiterChar = '=';
string[] sections = youtubePlaylistUnParsed.Split(delimiterChar);
string YoutubePlaylist = sections[1];
This gets me the playlist in the PLs__ etc. form for use in the Google APIs.