ASP. NET converts an absolute path under a Web site to a virtual path

I often use a feature, but I have not found any related solutions on the Internet. Today I have written two methods for converting absolute paths to virtual paths through project application.
Converts an absolute path under a Web site to a virtual path relative to a specified page.
/// <Summary>
/// Convert the absolute path under the web site to the virtual path relative to the specified page
/// </Summary>
/// <Param name = "page"> current page pointer, which is generally this </param>
/// <Param name = "specifiedpath"> absolute path </param>
/// <Returns> virtual path, type such as: http://www.cnblogs.com/</returns>
Public static string convertspecifiedpathtore Lativepathforpage (page, string specifiedpath)
{
// Root directory Virtual Path
String virtualpath = page. Request. applicationpath;
// Absolute path of the root directory
String pathrooted = hostingenvironment. mappath (virtualpath );
// Page Virtual Path
String pagevirtualpath = page. Request. path;

If (! Path. ispathrooted (specifiedpath) specifiedpath. indexof (pathrooted) =-1)
{< br> throw new exception (string. format ("\" {0} \ "is a virtual path rather than an absolute path! ", Specifiedpath);
}

   // Convert to relative path
   // (The test showed that the server that comes with pathrooted in vs2005 does not seem to run in the root directory or virtual directory of IIS,
   // "\" Will be added at the end of this place, and some will not. Please check for the sake of insurance)
   If (pathrooted. substring (pathrooted. Length-1, 1) = "\\")
   {
       Specifiedpath = specifiedpath. Replace (pathrooted ,"/");
   }
   Else
   {
       Specifiedpath = specifiedpath. Replace (pathrooted ,"");
   }

   String relativepath = specifiedpath. Replace ("\\","/");

   String [] pagenodes = pagevirtualpath. Split ('/');

   // Subtract the last page and the previous "" Value
Int pagenodescount = pagenodes. Length-2;

 

   For (INT I = 0; I <pagenodescount; I ++)
   {
       Relativepath = "/..." + relativepath;
   }

   If (pagenodescount> 0)
   {
       // If "..." exists, remove the first "/"
       Relativepath = relativepath. substring (1, relativepath. Length-1 );
   }

   Return relativepath;
}

The second method is extracted from the first part of the first method.
Converts an absolute path under a Web site to a virtual path.
/// <Summary>
/// Convert the absolute path under the web site to a virtual path
/// Note: Non-web sites do not convert
/// </Summary>
/// <Param name = "page"> current page pointer, which is generally this </param>
/// <Param name = "specifiedpath"> absolute path </param>
/// <Returns> virtual path, for example :~ /</Returns>
Public static string convertspecifiedpathtoreLativepath (page, string specifiedpath)

{
   String virtualpath = page. Request. applicationpath;

   String pathrooted = hostingenvironment. mappath (virtualpath );

   If (! Path. ispathrooted (specifiedpath) specifiedpath. indexof (pathrooted) =-1)
   {
       Return specifiedpath;
   }

   If (pathrooted. substring (pathrooted. Length-1, 1) = "\\")
   {
       Specifiedpath = specifiedpath. Replace (pathrooted ,"~ /");
   }
   Else
   {
       Specifiedpath = specifiedpath. Replace (pathrooted ,"~ ");
}

 

   String relativepath = specifiedpath. Replace ("\\","/");
   Return relativepath;
}

There is nothing to say about converting a virtual path to an absolute path. The httprequest. mappath method is dedicated to doing this.

From: http://blog.sina.com.cn/s/blog_4efce4d10100clcj.html ~ Type = v5_one & label = rela_prevarticle