

I'm looking for syntax like this:

Url.Combine("http://MyUrl.com/", "/Images/Image.jpg")

which would return:


  • 12
    Flurl includes a Url.Combine method that does just that. – Todd Menier Feb 21 '14 at 6:18
  • 1
    Actually, the // is handled by the routing of the website or server and not by the browser. It will send what you put into the address bar. That's why we get problems when we type htp:// instead of http:// So the // can cause major problems on some sites. I am writing a .dll for a crawler which handles a particular website which throws a 404 if you have // in the url. – Dave Gordon Jul 7 '14 at 8:11

33 Answers 33


There is a Todd Menier's comment above that Flurl includes a Url.Combine.

More details:

Url.Combine is basically a Path.Combine for URLs, ensuring one and only one separator character between parts:

var url = Url.Combine(
    "/too/", "/many/", "/slashes/",
    "too", "few?",
    "x=1", "y=2"
// result: "http://www.foo.com/too/many/slashes/too/few?x=1&y=2" 

Get Flurl.Http on NuGet:

PM> Install-Package Flurl.Http

Or get the stand-alone URL builder without the HTTP features:

PM> Install-Package Flurl

  • 3
    Well, this question gets a lot of traffic, and the answer with 1000+ upvotes does not actually work in all cases. Years later, I actually use Flurl for this, so I am accepting this one. It seems to work in all cases I have encountered. If people don't want to take a dependency, I posted an answer that also works fine. – Brian MacKay Nov 28 '18 at 15:33
  • and if you dont use Flurl and would perfer a lightweight version, github.com/jean-lourenco/UrlCombine – lizzy91 Feb 1 at 19:59


Here's an example:

Uri baseUri = new Uri("http://www.contoso.com");

Note from editor: Beware, this method does not work as expected. It can cut part of baseUri in some cases. See comments and other answers.

  • 337
    I like the use of the Uri class, unfortunately it will not behave like Path.Combine as the OP asked. For example new Uri(new Uri("test.com/mydirectory/"), "/helloworld.aspx").ToString() gives you "test.com/helloworld.aspx"; which would be incorrect if we wanted a Path.Combine style result. – Doctor Jones Oct 28 '10 at 15:20
  • 172
    It's all in the slashes. If the relative path part starts with a slash, then it behaves as you described. But, if you leave the slash out, then it works the way you'd expect (note the missing slash on the second parameter): new Uri(new Uri("test.com/mydirectory/"), "helloworld.aspx").ToString() results in "test.com/mydirectory/helloworld.aspx". Path.Combine behaves similarly. If the relative path parameter starts with a slash, it only returns the relative path and doesn't combine them. – Joel Beckham Oct 28 '10 at 22:11
  • 62
    If your baseUri happened to be "test.com/mydirectory/mysubdirectory" then the result would be "test.com/mydirectory/helloworld.aspx" instead of "test.com/mydirectory/mysubdirectory/helloworld.aspx". The subtle difference is the lack of trailing slash on the first parameter. I'm all for using existing framework methods, if I have to have the trailing slash there already then I think that doing partUrl1 + partUrl2 smells a lot less - I could've potentially been chasing that trailing slash round for quite a while all for the sake of not doing string concat. – Carl Jan 12 '11 at 16:10
  • 58
    The only reason I want a URI combine method is so that I don't have to check for the trailing slash. Request.ApplicationPath is '/' if your application is at the root, but '/foo' if it's not. – nickd Mar 25 '11 at 16:44
  • 19
    I -1 this answer because this doesn't answer the problem. When you want to combine url, like when you want to use Path.Combine, you don't want to care about the trailing /. and with this, you have to care. I prefer solution of Brian MacKay or mdsharpe above – Baptiste Pernet Apr 21 '11 at 15:56

You use Uri.TryCreate( ... ) :

Uri result = null;

if (Uri.TryCreate(new Uri("http://msdn.microsoft.com/en-us/library/"), "/en-us/library/system.uri.trycreate.aspx", out result))

Will return:


  • 49
    +1: This is good, although I have an irrational problem with the output parameter. ;) – Brian MacKay Oct 29 '09 at 14:24
  • 10
    @Brian: if it helps, all TryXXX methods (int.TryParse, DateTime.TryParseExact) have this output param to make it easier to use them in an if-statement. Btw, you don't have to initialize the variable as Ryan did in this example. – Abel Aug 26 '10 at 22:11
  • 34
    This answer suffers the same problem as Joel's: joining test.com/mydirectory/ and /helloworld.aspx will result in test.com/helloworld.aspx which is seemingly not what you want. – Matt Kocaj Aug 27 '13 at 2:05
  • 3
    Hi, this failed for following : if (Uri.TryCreate(new Uri("localhost/MyService/"), "/Event/SomeMethod?abc=123", out result)) { Console.WriteLine(result); } It is showing me result as : localhost/Event/SomeMethod?abc=123 Note: "http://" is replaced from base Uri here by stackoverflow – Faisal Mq Nov 28 '13 at 8:45
  • 3
    @FaisalMq This is the correct behavior, since you passed a root-relative second parameter. If you had left out the leading / on the second parameter, you'd have gotten the result you expected. – Tom Lint Jan 24 '14 at 9:17

This may be a suitably simple solution:

public static string Combine(string uri1, string uri2)
    uri1 = uri1.TrimEnd('/');
    uri2 = uri2.TrimStart('/');
    return string.Format("{0}/{1}", uri1, uri2);
  • 7
    +1: Although this doesn't handle relative-style paths (../../whatever.html), I like this one for its simplicity. I would also add trims for the '\' character. – Brian MacKay May 8 '10 at 15:55
  • 3
    See my answer for a more fully fleshed out version of this. – Brian MacKay May 12 '10 at 13:46

There's already some great answers here. Based on mdsharpe suggestion, here's an extension method that can easily be used when you want to deal with Uri instances:

using System;
using System.Linq;

public static class UriExtensions
    public static Uri Append(this Uri uri, params string[] paths)
        return new Uri(paths.Aggregate(uri.AbsoluteUri, (current, path) => string.Format("{0}/{1}", current.TrimEnd('/'), path.TrimStart('/'))));

And usage example:

var url = new Uri("http://example.com/subpath/").Append("/part1/", "part2").AbsoluteUri;

This will produce http://example.com/subpath/part1/part2

  • 2
    This solution makes it trivial to write a UriUtils.Combine("base url", "part1", "part2", ...) static method that is very similar to Path.Combine(). Nice! – angularsen Nov 19 '11 at 15:23
  • To support relative URIs I had to use ToString() instead of AbsoluteUri and UriKind.AbsoluteOrRelative in the Uri constructor. – angularsen Nov 20 '11 at 19:34
  • Thanks for the tip about relative Uris. Unfortunately Uri doesn't make it easy to deal with relative paths as there is always some mucking about with Request.ApplicationPath involved. Perhaps you could also try using new Uri(HttpContext.Current.Request.ApplicationPath) as a base and just call Append on it? This will give you absolute paths but should work anywhere within site structure. – Ales Potocnik Hahonina Nov 21 '11 at 12:03
  • Great. Glad it helped someone else. Been using this for some time now and haven't had any issues. – Ales Potocnik Hahonina Jul 8 '13 at 8:58
  • I also added check if any of paths to append are not null nor empty string. – n.podbielski Jan 15 '16 at 10:13

Ryan Cook's answer is close to what I'm after and may be more appropriate for other developers. However, it adds http:// to the beginning of the string and in general it does a bit more formatting than I'm after.

Also, for my use cases, resolving relative paths is not important.

mdsharp's answer also contains the seed of a good idea, although that actual implementation needed a few more details to be complete. This is an attempt to flesh it out (and I'm using this in production):


public string UrlCombine(string url1, string url2)
    if (url1.Length == 0) {
        return url2;

    if (url2.Length == 0) {
        return url1;

    url1 = url1.TrimEnd('/', '\\');
    url2 = url2.TrimStart('/', '\\');

    return string.Format("{0}/{1}", url1, url2);


Public Function UrlCombine(ByVal url1 As String, ByVal url2 As String) As String
    If url1.Length = 0 Then
        Return url2
    End If

    If url2.Length = 0 Then
        Return url1
    End If

    url1 = url1.TrimEnd("/"c, "\"c)
    url2 = url2.TrimStart("/"c, "\"c)

    Return String.Format("{0}/{1}", url1, url2)
End Function

This code passes the following test, which happens to be in VB:

<TestMethod()> Public Sub UrlCombineTest()
    Dim target As StringHelpers = New StringHelpers()

    Assert.IsTrue(target.UrlCombine("test1", "test2") = "test1/test2")
    Assert.IsTrue(target.UrlCombine("test1/", "test2") = "test1/test2")
    Assert.IsTrue(target.UrlCombine("test1", "/test2") = "test1/test2")
    Assert.IsTrue(target.UrlCombine("test1/", "/test2") = "test1/test2")
    Assert.IsTrue(target.UrlCombine("/test1/", "/test2/") = "/test1/test2/")
    Assert.IsTrue(target.UrlCombine("", "/test2/") = "/test2/")
    Assert.IsTrue(target.UrlCombine("/test1/", "") = "/test1/")
End Sub
  • 4
    Talking of details: what about the mandatory ArgumentNullException("url1") if the argument is Nothing? Sorry, just being picky ;-). Note that a backslash has nothing to do in a URI (and if it is there, it should not be trimmed), so you can remove that from your TrimXXX. – Abel Aug 26 '10 at 22:21
  • 4
    you can use params string[] and recursively join them to allow more than 2 combinations – Jaider Jun 12 '12 at 22:47
  • 4
    I sure wish this was in the Base Class Library like Path.Combine. – Uriah Blatherwick Aug 18 '14 at 18:30
  • 1
    @MarkHurd I edited the code again, so that it's behaviorally the same as the C#, and syntactically equivalent as well. – JJS Jul 7 '16 at 19:23
  • 1
    @BrianMacKay i broke it, markhurd pointed out my mistake and rolled back, i updated again... cheers – JJS Jul 11 '16 at 13:28

Based on the sample URL you provided, I'm going to assume you want to combine URLs that are relative to your site.

Based on this assumption I'll propose this solution as the most appropriate response to your question which was: "Path.Combine is handy, is there a similar function in the framework for URLs?"

Since there the is a similar function in the framework for URLs I propose the correct is: "VirtualPathUtility.Combine" method. Here's the MSDN reference link: VirtualPathUtility.Combine Method

There is one caveat: I believe this only works for URLs relative to your site (that is, you cannot use it to generate links to another web site. For example, var url = VirtualPathUtility.Combine("www.google.com", "accounts/widgets");).

  • +1 because it's close to what I'm looking for, although it would be ideal if it would work for any old url. I double it will get much more elegant than what mdsharpe proposed. – Brian MacKay Mar 29 '10 at 21:28
  • 2
    The caveat is correct, it cannot work with absolute uris and the result is always relative from the root. But it has an added benefit, it processes the tilde, as with "~/". This makes it a shortcut for Server.MapPath and combining. – Abel Aug 26 '10 at 22:18

Path.Combine does not work for me because there can be characters like "|" in QueryString arguments and therefore the URL, which will result in an ArgumentException.

I first tried the new Uri(Uri baseUri, string relativeUri) approach, which failed for me because of URIs like http://www.mediawiki.org/wiki/Special:SpecialPages:

new Uri(new Uri("http://www.mediawiki.org/wiki/"), "Special:SpecialPages")

will result in Special:SpecialPages, because of the colon after Special that denotes a scheme.

So I finally had to take mdsharpe/Brian MacKays route and developed it a bit further to work with multiple URI parts:

public static string CombineUri(params string[] uriParts)
    string uri = string.Empty;
    if (uriParts != null && uriParts.Count() > 0)
        char[] trims = new char[] { '\\', '/' };
        uri = (uriParts[0] ?? string.Empty).TrimEnd(trims);
        for (int i = 1; i < uriParts.Count(); i++)
            uri = string.Format("{0}/{1}", uri.TrimEnd(trims), (uriParts[i] ?? string.Empty).TrimStart(trims));
    return uri;

Usage: CombineUri("http://www.mediawiki.org/", "wiki", "Special:SpecialPages")

  • 1
    +1: Now we're talking... I'm going to try this out. This might even end up being the new accepted answer. After trying to new Uri() method I really don't like it. Too finnicky. – Brian MacKay Jul 18 '11 at 14:23
  • This is exactly what I needed! Was not a fan of having to care where I put trailing slashes, etc... – Gromer Aug 6 '12 at 21:52
  • +1 for rolling in the null checking so it won't blow up. – NightOwl888 Mar 6 '14 at 13:34
Path.Combine("Http://MyUrl.com/", "/Images/Image.jpg").Replace("\\", "/")
  • 8
    path.Replace(Path.DirectorySeparatorChar, '/'); – Jaider Jun 12 '12 at 22:51
  • 4
    path.Replace(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar) – SliverNinja - MSFT Aug 16 '12 at 14:31
  • 1
    To get it to wrk u must remove first / in second arg ie "/Images" - / Path.Combine("Http://MyUrl.com", "Images/Image.jpg") – Per G Apr 25 '13 at 10:43
  • 7
    @SliverNinja That's not correct The value of this field is a backslash ('\') on UNIX, and a slash ('/') on Windows and Macintosh operating systems. When using Mono on a Linux system, you'd get the wrong separator. – Stijn Mar 13 '14 at 10:01
  • 3
    All yall that are geeking out on the Directory Separator are forgetting that the strings could have come from a different OS than you are on now. Just replace backslash with forward slash and you're covered. – JeremyWeir Jul 26 '16 at 22:43

I just put together a small extension method:

public static string UriCombine (this string val, string append)
            if (String.IsNullOrEmpty(val)) return append;
            if (String.IsNullOrEmpty(append)) return val;
            return val.TrimEnd('/') + "/" + append.TrimStart('/');

It can be used like this:


Witty example, Ryan, to end with a link to the function. Well done.

One recommendation Brian: if you wrap this code in a function, you may want to use a UriBuilder to wrap the base URL prior to the TryCreate call.

Otherwise, the base URL MUST include the scheme (where the UriBuilder will assume http://). Just a thought:

public string CombineUrl(string baseUrl, string relativeUrl) {
    UriBuilder baseUri = new UriBuilder(baseUrl);
    Uri newUri;

    if (Uri.TryCreate(baseUri.Uri, relativeUrl, out newUri))
        return newUri.ToString();
        throw new ArgumentException("Unable to combine specified url values");

Combining multiple parts of a URL could be a little bit tricky. You can use the two-parameter constructor Uri(baseUri, relativeUri), or you can use the Uri.TryCreate() utility function.

In either case, you might end up returning an incorrect result because these methods keep on truncating the relative parts off of the first parameter baseUri, i.e. from something like http://google.com/some/thing to http://google.com.

To be able to combine multiple parts into a final URL, you can copy the two functions below:

    public static string Combine(params string[] parts)
        if (parts == null || parts.Length == 0) return string.Empty;

        var urlBuilder = new StringBuilder();
        foreach (var part in parts)
            var tempUrl = tryCreateRelativeOrAbsolute(part);
        return VirtualPathUtility.RemoveTrailingSlash(urlBuilder.ToString());

    private static string tryCreateRelativeOrAbsolute(string s)
        System.Uri uri;
        System.Uri.TryCreate(s, UriKind.RelativeOrAbsolute, out uri);
        string tempUrl = VirtualPathUtility.AppendTrailingSlash(uri.ToString());
        return tempUrl;

Full code with unit tests to demonstrate usage can be found at https://uricombine.codeplex.com/SourceControl/latest#UriCombine/Uri.cs

I have unit tests to cover the three most common cases:

Enter image description here

  • 1
    Looks pretty good to me. Although you could replace the I loop with a foreach loop for better clarity. – Chris Marisic May 1 '14 at 18:55
  • Thanks Chris. I have just changed my code to use Foreach. – Believe2014 May 2 '14 at 4:03
  • 1
    +1 for all the extra effort. I need to maintain this question a bit for some of the higher voted answers, you have thrown down the gauntlet. ;) – Brian MacKay May 4 '14 at 11:42
  • Sorry, but not enough. Works in the few cases you show but far from being usable in al combinations. For instance, colons in the path will cause harm. – Gábor May 13 '18 at 20:43
  • Can you please give an example of what you mean? I will be happy to fix the issue and help the next users. – Believe2014 May 14 '18 at 21:23

An easy way to combine them and ensure it's always correct is:

string.Format("{0}/{1}", Url1.Trim('/'), Url2);
  • +1, although this is very similiar to mdsharpe's answer, which I improved upon in my answer. This version works great unless Url2 starts with / or \, or Url1 accidentally ends in \, or either one is empty! :) – Brian MacKay May 12 '10 at 23:57

I found UriBuilder worked really well for this sort of thing:

UriBuilder urlb = new UriBuilder("http", _serverAddress, _webPort, _filePath);
Uri url = urlb.Uri;
return url.AbsoluteUri;

See UriBuilder Class - MSDN for more constructors and documentation.


Here's Microsoft's (OfficeDev PnP) method UrlUtility.Combine:

    const char PATH_DELIMITER = '/';

    /// <summary>
    /// Combines a path and a relative path.
    /// </summary>
    /// <param name="path"></param>
    /// <param name="relative"></param>
    /// <returns></returns>
    public static string Combine(string path, string relative) 
        if(relative == null)
            relative = String.Empty;

        if(path == null)
            path = String.Empty;

        if(relative.Length == 0 && path.Length == 0)
            return String.Empty;

        if(relative.Length == 0)
            return path;

        if(path.Length == 0)
            return relative;

        path = path.Replace('\\', PATH_DELIMITER);
        relative = relative.Replace('\\', PATH_DELIMITER);

        return path.TrimEnd(PATH_DELIMITER) + PATH_DELIMITER + relative.TrimStart(PATH_DELIMITER);

Source: GitHub

  • It looks like this might be for paths, rather than URLs. – Brian MacKay Nov 2 '15 at 18:12
  • @BrianMacKay Agreed that it looks like it, but it's from the UrlUtility class and used in the context of combining URLs – user3638471 Nov 3 '15 at 19:55
  • 2
    Edited to clarify what class it belongs to – user3638471 Nov 3 '15 at 19:57
  • Take care when using this Class, the rest of the class contains SharePoint specific artifacts. – Harry Berry Sep 26 '17 at 12:55

My generic solution:

public static string Combine(params string[] uriParts)
    string uri = string.Empty;
    if (uriParts != null && uriParts.Any())

        for (int i = 1; i < uriParts.Length; i++)

    return uri;
  • This helper method is very flexible and works well in many different use cases. Thank you! – Shiva May 22 '17 at 5:11

I created this function that will make your life easier:

    /// <summary>
    /// The ultimate Path combiner of all time
    /// </summary>
    /// <param name="IsURL">
    /// true - if the paths are Internet URLs, false - if the paths are local URLs, this is very important as this will be used to decide which separator will be used.
    /// </param>
    /// <param name="IsRelative">Just adds the separator at the beginning</param>
    /// <param name="IsFixInternal">Fix the paths from within (by removing duplicate separators and correcting the separators)</param>
    /// <param name="parts">The paths to combine</param>
    /// <returns>the combined path</returns>
    public static string PathCombine(bool IsURL , bool IsRelative , bool IsFixInternal , params string[] parts)
        char separator = IsURL ? '/' : '\\';

        if (parts.Length == 1 && IsFixInternal)
            string validsingle;
            if (IsURL)
                validsingle = parts[0].Replace('\\' , '/');
                validsingle = parts[0].Replace('/' , '\\');
            validsingle = validsingle.Trim(separator);
            return (IsRelative ? separator.ToString() : string.Empty) + validsingle;

        string final = parts
            (string first , string second) =>
                string validfirst;
                string validsecond;
                if (IsURL)
                    validfirst = first.Replace('\\' , '/');
                    validsecond = second.Replace('\\' , '/');
                    validfirst = first.Replace('/' , '\\');
                    validsecond = second.Replace('/' , '\\');
                var prefix = string.Empty;
                if (IsFixInternal)
                    if (IsURL)
                        if (validfirst.Contains("://"))
                            var tofix = validfirst.Substring(validfirst.IndexOf("://") + 3);
                            prefix = validfirst.Replace(tofix , string.Empty).TrimStart(separator);

                            var tofixlist = tofix.Split(new[] { separator } , StringSplitOptions.RemoveEmptyEntries);

                            validfirst = separator + string.Join(separator.ToString() , tofixlist);
                            var firstlist = validfirst.Split(new[] { separator } , StringSplitOptions.RemoveEmptyEntries);
                            validfirst = string.Join(separator.ToString() , firstlist);

                        var secondlist = validsecond.Split(new[] { separator } , StringSplitOptions.RemoveEmptyEntries);
                        validsecond = string.Join(separator.ToString() , secondlist);

                        validfirst = string.Join(separator.ToString() , firstlist);
                        validsecond = string.Join(separator.ToString() , secondlist);
                return prefix + validfirst.Trim(separator) + separator + validsecond.Trim(separator);
        return (IsRelative ? separator.ToString() : string.Empty) + final;

It works for URLs as well as normal paths.


    // Fixes internal paths
    Console.WriteLine(PathCombine(true , true , true , @"\/\/folder 1\/\/\/\\/\folder2\///folder3\\/" , @"/\somefile.ext\/\//\"));
    // Result: /folder 1/folder2/folder3/somefile.ext

    // Doesn't fix internal paths
    Console.WriteLine(PathCombine(true , true , false , @"\/\/folder 1\/\/\/\\/\folder2\///folder3\\/" , @"/\somefile.ext\/\//\"));
    //result : /folder 1//////////folder2////folder3/somefile.ext

    // Don't worry about URL prefixes when fixing internal paths
    Console.WriteLine(PathCombine(true , false , true , @"/\/\/https:/\/\/\lul.com\/\/\/\\/\folder2\///folder3\\/" , @"/\somefile.ext\/\//\"));
    // Result: https://lul.com/folder2/folder3/somefile.ext

    Console.WriteLine(PathCombine(false , true , true , @"../../../\\..\...\./../somepath" , @"anotherpath"));
    // Result: \..\..\..\..\...\.\..\somepath\anotherpath

I find the following useful and has the following features :

  • Throws on null or white space
  • Takes multiple params parameter for multiple Url segments
  • throws on null or empty


public static class UrlPath
   private static string InternalCombine(string source, string dest)
      if (string.IsNullOrWhiteSpace(source))
         throw new ArgumentException("Cannot be null or white space", nameof(source));

      if (string.IsNullOrWhiteSpace(dest))
         throw new ArgumentException("Cannot be null or white space", nameof(dest));

      return $"{source.TrimEnd('/', '\\')}/{dest.TrimStart('/', '\\')}";

   public static string Combine(string source, params string[] args) 
       => args.Aggregate(source, InternalCombine);


UrlPath.Combine("test1", "test2");
UrlPath.Combine("test1//", "test2");
UrlPath.Combine("test1", "/test2");

// Result = test1/test2

UrlPath.Combine(@"test1\/\/\/", @"\/\/\\\\\//test2", @"\/\/\\\\\//test3\") ;

// Result = test1/test2/test3

UrlPath.Combine("/test1/", "/test2/", null);
UrlPath.Combine("", "/test2/");
UrlPath.Combine("/test1/", null);

// Throws an ArgumentException
  • @PeterMortensen thanks for the edit – TheGeneral Oct 18 '18 at 23:14

Rules while combining URLs with a URI

To avoid strange behaviour there's one rule to follow:

  • The path (directory) must end with '/'. If the path ends without '/', the last part is treated like a file-name, and it'll be concatenated when trying to combine with the next URL part.
  • There's one exception: the base URL address (without directory info) needs not to end with '/'
  • the path part must not start with '/'. If it start with '/', every existing relative information from URL is dropped...adding a string.Empty part path will remove the relative directory from the URL too!

If you follow rules above, you can combine URLs with the code below. Depending on your situation, you can add multiple 'directory' parts to the URL...

        var pathParts = new string[] { destinationBaseUrl, destinationFolderUrl, fileName };

        var destination = pathParts.Aggregate((left, right) =>
            if (string.IsNullOrWhiteSpace(right))
                return left;

            return new Uri(new Uri(left), right).ToString();


    private Uri UriCombine(string path1, string path2, string path3 = "", string path4 = "")
        string path = System.IO.Path.Combine(path1, path2.TrimStart('\\', '/'), path3.TrimStart('\\', '/'), path4.TrimStart('\\', '/'));
        string url = path.Replace('\\','/');
        return new Uri(url);

It has the benefit of behaving exactly like Path.Combine.


Here is my approach and I will use it for myself too:

public static string UrlCombine(string part1, string part2)
    string newPart1 = string.Empty;
    string newPart2 = string.Empty;
    string seperator = "/";

    // If either part1 or part 2 is empty,
    // we don't need to combine with seperator
    if (string.IsNullOrEmpty(part1) || string.IsNullOrEmpty(part2))
        seperator = string.Empty;

    // If part1 is not empty,
    // remove '/' at last
    if (!string.IsNullOrEmpty(part1))
        newPart1 = part1.TrimEnd('/');

    // If part2 is not empty,
    // remove '/' at first
    if (!string.IsNullOrEmpty(part2))
        newPart2 = part2.TrimStart('/');

    // Now finally combine
    return string.Format("{0}{1}{2}", newPart1, seperator, newPart2);
  • This is acceptable only for your case. There are cases which could broke your code. Also, you didn't do proper encoding of the parts of the path. This could be a huge vulnerability when it comes to cross site scripting attack. – Believe2014 May 1 '14 at 15:40
  • I agree to your points. The code is supposed to do just simple combining of two url parts. – Amit Bhagat May 2 '14 at 3:14

Use this:

public static class WebPath
    public static string Combine(params string[] args)
        var prefixAdjusted = args.Select(x => x.StartsWith("/") && !x.StartsWith("http") ? x.Substring(1) : x);
        return string.Join("/", prefixAdjusted);
  • Nice touch with 'WebPath'. :) The code might be unecessarily dense though - it's hard for me to glance at this and say, yes, that's perfect. It makes me want to see unit tests. Maybe that's just me! – Brian MacKay Dec 10 '12 at 21:42
  • 1
    x.StartsWith("/") && !x.StartsWith("http") - why the http check? what do you gain? – penguat Dec 13 '12 at 10:03
  • You don't want to try to strip off the slash if it starts with http. – Martin Murphy Apr 16 '13 at 16:12
  • @BrianMacKay, I'm not sure a two liner warrants a unit test but if you like feel free to provide one. It's not like I'm accepting patches or anything, but feel free to edit the suggestion. – Martin Murphy Apr 16 '13 at 16:23

I found that the Uri constructor flips '\' into '/'. So you can also use Path.Combine, with the Uri constructor.

 Uri baseUri = new Uri("http://MyUrl.com");
 string path = Path.Combine("Images", "Image.jpg");
 Uri myUri = new Uri(baseUri, path);

Why not just use the following.

System.IO.Path.Combine(rootUrl, subPath).Replace(@"\", "/")
  • I was looking for the PowerShell version of this which would be: [System.IO.Path]::Combine("http://MyUrl.com/","/Images/Image.jpg")however this fails with a result of: /Images/Image.jpg. Remove the / from the second subPath and it works: [System.IO.Path]::Combine("http://MyUrl.com/","Images/Image.jpg") – Underverse Feb 6 '18 at 0:14
  • Nice idea, but it fails, when one of the parameter is null. – pholpar Mar 22 '18 at 14:19

I used this code to solve the problem:

string[] brokenBaseUrl = Context.Url.TrimEnd('/').Split('/');
string[] brokenRootFolderPath = RootFolderPath.Split('/');

for (int x = 0; x < brokenRootFolderPath.Length; x++)
    //if url doesn't already contain member, append it to the end of the string with / in front
    if (!brokenBaseUrl.Contains(brokenRootFolderPath[x]))
        if (x == 0)
            RootLocationUrl = Context.Url.TrimEnd('/');
            RootLocationUrl += String.Format("/{0}", brokenRootFolderPath[x]);

A simple one liner:

public static string Combine(this string uri1, string uri2) => $"{uri1.TrimEnd('/')}/{uri2.TrimStart('/')}";

Inspired by @Matt Sharpe's answer.


Well, I just concatenate two strings and use regular expressions to do the cleaning part.

    public class UriTool
        public static Uri Join(string path1, string path2)
            string url = path1 + "/" + path2;
            url = Regex.Replace(url, "(?<!http:)/{2,}", "/");

            return new Uri(url);

So, you can use it like this:

    string path1 = "http://someaddress.com/something/";
    string path2 = "/another/address.html";
    Uri joinedUri = UriTool.Join(path1, path2);

    // joinedUri.ToString() returns "http://someaddress.com/something/another/address.html"

I have combined all the previous answers:

    public static string UrlPathCombine(string path1, string path2)
        path1 = path1.TrimEnd('/') + "/";
        path2 = path2.TrimStart('/');

        return Path.Combine(path1, path2)
            .Replace(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar);

    public void TestUrl()
        const string P1 = "http://msdn.microsoft.com/slash/library//";
        Assert.AreEqual("http://msdn.microsoft.com/slash/library/site.aspx", UrlPathCombine(P1, "//site.aspx"));

        var path = UrlPathCombine("Http://MyUrl.com/", "Images/Image.jpg");


Both of these work:

  Uri final = new Uri(Regex.Replace(baseUrl + "/" + relativePath, "(?<!http:)/{2,}", "/"));


  Uri final =new Uri(string.Format("{0}/{1}", baseUrl.ToString().TrimEnd('/'), relativePath.ToString().TrimStart('/')));

I.e. if

baseUrl = "http://tesrurl.test.com/Int18"


relativePath = "To_Folder"

output = http://tesrurl.test.com/Int18/To_Folder

Some errors will appear for the code below:

 // If you use the below code, some issues will be there in the final URI
 Uri final = new Uri(baseUrl, relativePath);

We use the following simple helper method to join an arbitrary number of URL parts together:

public static string JoinUrlParts(params string[] urlParts)
    return string.Join("/", urlParts.Where(up => !string.IsNullOrEmpty(up)).ToList().Select(up => up.Trim('/')).ToArray());

Note, that it doesn't support '../../something/page.htm'-style relative URLs!

protected by Sheridan Oct 22 '14 at 14:51


Would you like to answer one of these unanswered questions instead?
