C＃通过ID获取已知文件夹的位置

Question

我想通过ID获取目录/文件夹的位置。
例如，下载文件夹的ID为knownfolder:{374DE290-123F-4565-9164-39C4925E467B}，当我将其输入到Windows资源管理器的地址栏中时，它将我重定向到下载文件夹。

有这些ID和相应的文件夹here的列表，所以我可以硬编码ID和找一找这样，但我不会想这样做，除非它的唯一途径。

有没有另一种方法来正确得到我想要的？

Answer 1

被盗从here。望着这进一步，唯一的办法是使用WinAPI的/ PInvoke的

public static class KnownFolderFinder 
{ 
    private static readonly Guid CommonDocumentsGuid = new Guid("ED4824AF-DCE4-45A8-81E2-FC7965083634"); 

    [Flags] 
    public enum KnownFolderFlag : uint 
    { 
     None = 0x0, 
     CREATE = 0x8000, 
     DONT_VERFIY = 0x4000, 
     DONT_UNEXPAND= 0x2000, 
     NO_ALIAS = 0x1000, 
     INIT = 0x800, 
     DEFAULT_PATH = 0x400, 
     NOT_PARENT_RELATIVE = 0x200, 
     SIMPLE_IDLIST = 0x100, 
     ALIAS_ONLY = 0x80000000 
    } 

    [DllImport("shell32.dll")] 
    static extern int SHGetKnownFolderPath([MarshalAs(UnmanagedType.LPStruct)] Guid rfid, uint dwFlags, IntPtr hToken, out IntPtr pszPath); 

    public static string GetFolderFromKnownFolderGUID(Guid guid) 
    { 
     return pinvokePath(guid, KnownFolderFlag.DEFAULT_PATH); 
    } 

    public static void EnumerateKnownFolders() 
    { 
     KnownFolderFlag[] flags = new KnownFolderFlag[] { 
      KnownFolderFlag.None, 
      KnownFolderFlag.ALIAS_ONLY | KnownFolderFlag.DONT_VERFIY, 
      KnownFolderFlag.DEFAULT_PATH | KnownFolderFlag.NOT_PARENT_RELATIVE, 
     }; 


     foreach (var flag in flags) 
     { 
      Console.WriteLine(string.Format("{0}; P/Invoke==>{1}", flag, pinvokePath(CommonDocumentsGuid, flag))); 
     } 
     Console.ReadLine(); 
    } 

    private static string pinvokePath(Guid guid, KnownFolderFlag flags) 
    { 
     IntPtr pPath; 
     SHGetKnownFolderPath(guid, (uint)flags, IntPtr.Zero, out pPath); // public documents 

     string path = System.Runtime.InteropServices.Marshal.PtrToStringUni(pPath); 
     System.Runtime.InteropServices.Marshal.FreeCoTaskMem(pPath); 
     return path; 
    } 
} 

然后你可以称之为是这样做的：

var folder = KnownFolderFinder.GetFolderFromKnownFolderGUID(new Guid("374DE290-123F-4565-9164-39C4925E467B"); 

Answer 2

我认为你正在寻找Environment.SpecialFolder（System命名空间）：

https://msdn.microsoft.com/en-us/library/system.environment.specialfolder(v=vs.110).aspx

// Sample for the Environment.GetFolderPath method 
using System; 

class Sample 
{ 
    public static void Main() 
{ 
Console.WriteLine(); 
Console.WriteLine("GetFolderPath: {0}", 
      Environment.GetFolderPath(Environment.SpecialFolder.System)); 
} 
    } 
/* 
This example produces the following results: 

GetFolderPath: C:\WINNT\System32 
*/