如何以编程方式派生Windows下载文件夹“％USERPROFILE％/ Downloads”？

Question

在.Net中，我们可以检索“特殊文件夹”的路径，例如Documents / Desktop等。今天我试图找到一种方法来获取“下载”文件夹的路径，但它看起来并不特别。

我知道我可以做'C：\ Users \ Username \ Downloads'，但这似乎是一个丑陋的解决方案。那么如何使用.Net来修复路径呢？

Answer 1

第一个答案的问题是，如果默认的下载目录已更改为[Download1]，它会给你错误的结果！覆盖所有可能性的正确方法是

using System;
using System.Runtime.InteropServices;

static class cGetEnvVars_WinExp    {
    [DllImport("Shell32.dll")] private static extern int SHGetKnownFolderPath(
        [MarshalAs(UnmanagedType.LPStruct)]Guid rfid, uint dwFlags, IntPtr hToken,
        out IntPtr ppszPath);

    [Flags] public enum KnownFolderFlags : uint { SimpleIDList = 0x00000100
        , NotParentRelative = 0x00000200, DefaultPath = 0x00000400, Init = 0x00000800
        , NoAlias = 0x00001000, DontUnexpand = 0x00002000, DontVerify = 0x00004000
        , Create = 0x00008000,NoAppcontainerRedirection = 0x00010000, AliasOnly = 0x80000000
    }
    public static string GetPath(string RegStrName, KnownFolderFlags flags, bool defaultUser) {
        IntPtr outPath;
        int result = 
            SHGetKnownFolderPath (
                new Guid(RegStrName), (uint)flags, new IntPtr(defaultUser ? -1 : 0), out outPath
            );
        if (result >= 0)            {
            return Marshal.PtrToStringUni(outPath);
        } else {
            throw new ExternalException("Unable to retrieve the known folder path. It may not "
                + "be available on this system.", result);
        }
    }

}   

要测试它，如果您特别需要个人下载目录，则将默认值标记为false - >

using System.IO;
class Program    {
    [STAThread]
    static void Main(string[] args)        {
        string path2Downloads = string.Empty;
        path2Downloads = 
            cGetEnvVars_WinExp.GetPath("{374DE290-123F-4565-9164-39C4925E467B}", cGetEnvVars_WinExp.KnownFolderFlags.DontVerify, false);
        string[] files = { "" };
        if (Directory.Exists(path2Downloads)) {
            files = Directory.GetFiles(path2Downloads);
        }
    }//Main
}

或者只是一行Environment.ExpandEnvironmentVariables（） - >（最简单的解决方案）。

using System.IO;
class Program    {
/* https://ss64.com/nt/syntax-variables.html */
    [STAThread]
    static void Main(string[] args)        {
        string path2Downloads = string.Empty;
        string[] files = { "" };
        path2Downloads = Environment.ExpandEnvironmentVariables(@"%USERPROFILE%\Downloads");
        if (Directory.Exists(path2Downloads)) {
            files = Directory.GetFiles(path2Downloads);
        }
    }//Main
}

Answer 2

是的，这是特别的，发现这个文件夹的名称直到Vista才成为可能。 .NET仍然需要支持以前的操作系统。你可以调用SHGetKnownFolderPath（）来绕过这个限制，如下所示：

using System.Runtime.InteropServices;
...

public static string GetDownloadsPath() {
    if (Environment.OSVersion.Version.Major < 6) throw new NotSupportedException();
    IntPtr pathPtr = IntPtr.Zero;
    try {
        SHGetKnownFolderPath(ref FolderDownloads, 0, IntPtr.Zero, out pathPtr);
        return Marshal.PtrToStringUni(pathPtr);
    }
    finally {
        Marshal.FreeCoTaskMem(pathPtr);
    }
}

private static Guid FolderDownloads = new Guid("374DE290-123F-4565-9164-39C4925E467B");
[DllImport("shell32.dll", CharSet = CharSet.Auto)]
private static extern int SHGetKnownFolderPath(ref Guid id, int flags, IntPtr token, out IntPtr path);

Answer 3

试试这个：

string path = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile)+ @"\Downloads";

Answer 4

我使用下面的代码，适用于Windows 7及更高版本的.net 4.6。下面的代码给出了用户配置文件夹路径 - > "C:\Users\<username>"

string userProfileFolder = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile);

在访问downloads文件夹旁边，只需合并其他路径字符串，如下所示：

string DownloadsFolder = userProfileFolder + "\\Downloads\\";

现在，最终结果将是

"C:\Users\<username>\Downloads\"

希望它为将来的某个人节省时间。

Answer 5

尝试：

Dim Dd As String = Environment.GetFolderPath(Environment.SpecialFolder.Favorites)
Dim downloD As String = Dd.Replace("Favorites", "Downloads")
txt1.text = downLoD

它只是一个技巧，而不是解决方案。

Answer 6

对于VB，试试......

Dim strNewPath As String = IO.Path.GetDirectoryName(Environment.GetFolderPath(Environment.SpecialFolder.Desktop)) + "\Downloads\"