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

你的第一个答案的问题是,如果默认的下载目录被更改为[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);
        }
    }

}   

为了测试它,如果您特别想要您的个人下载目录,您可以将default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);
        }
    }

是的,这是特别的,发现这个文件夹的名称是不可能的,直到Vista。NET仍然需要支持以前的操作系统。您可以pinvoke SHGetKnownFolderPath()绕过此限制,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);

试试这个:

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

这是对 accepted answer 因为IMO可以更好地实施:

public static class KnownFolders
{
    public static Guid Contacts = new Guid("{56784854-C6CB-462B-8169-88E350ACB882}");
    public static Guid Desktop = new Guid("{B4BFCC3A-DB2C-424C-B029-7FE99A87C641}");
    public static Guid Documents = new Guid("{FDD39AD0-238F-46AF-ADB4-6C85480369C7}");
    public static Guid Downloads = new Guid("{374DE290-123F-4565-9164-39C4925E467B}");
    public static Guid Favorites = new Guid("{1777F761-68AD-4D8A-87BD-30B759FA33DD}");
    public static Guid Links = new Guid("{BFB9D5E0-C6A9-404C-B2B2-AE6DB6AF4968}");
    public static Guid Music = new Guid("{4BD8D571-6D19-48D3-BE97-422220080E43}");
    public static Guid Pictures = new Guid("{33E28130-4E1E-4676-835A-98395C3BC3BB}");
    public static Guid SavedGames = new Guid("{4C5C32FF-BB9D-43B0-B5B4-2D72E54EAAA4}");
    public static Guid SavedSearches = new Guid("{7D1D3A04-DEBB-4115-95CF-2F29DA2920DA}");
    public static Guid Videos = new Guid("{18989B1D-99B5-455B-841C-AB7C74E4DDFC}");

    static Dictionary<string, Guid> Map { get; } = new Dictionary<string, Guid> {
        { nameof(Contacts), Contacts },
        { nameof(Desktop), Desktop },
        { nameof(Documents), Documents },
        { nameof(Downloads), Downloads },
        { nameof(Favorites), Favorites },
        { nameof(Links), Links },
        { nameof(Music), Music },
        { nameof(Pictures), Pictures },
        { nameof(SavedGames), SavedGames },
        { nameof(SavedSearches), SavedSearches },
        { nameof(Videos), Videos },
    };

    public static string GetPath(string knownFolder,
        KnownFolderFlags flags = KnownFolderFlags.DontVerify, bool defaultUser = false) =>
        Map.TryGetValue(knownFolder, out var knownFolderId)
            ? GetPath(knownFolderId, flags, defaultUser)
            : ThrowUnknownFolder();

    public static string GetPath(Guid knownFolderId, 
        KnownFolderFlags flags=KnownFolderFlags.DontVerify, bool defaultUser=false)
    {
        if (SHGetKnownFolderPath(knownFolderId, (uint)flags, new IntPtr(defaultUser ? -1 : 0), out var outPath) >= 0)
        {
            string path = Marshal.PtrToStringUni(outPath);
            Marshal.FreeCoTaskMem(outPath);
            return path;
        }
        return ThrowUnknownFolder();
    }

    //[DoesNotReturn]
    static string ThrowUnknownFolder() => 
        throw new NotSupportedException("Unable to retrieve the path for known folder. It may not be available on this system.");

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

可通过以下方式调用:

var downloadPath = KnownFolders.GetPath(KnownFolders.Downloads);

或者有时使用字符串获取它更方便:

var downloadPath = KnownFolders.GetPath(nameof(KnownFolders.Downloads));

"C:\Users\<username>"

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

在“访问下载”文件夹旁边,只需按以下方式组合其他路径字符串:

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

现在,最终结果将是

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

没那么难。如果你想得到下载文件夹目录运动模拟,只需执行以下步骤:

2.加载表单时添加此代码:

Special_directories.Text = Environment.GetFolderPath(Environment.SpecialFolder.UserProfile) & "\downloads\"

这将把标签文本设置为用户文件夹路径和“\downloads\”。 这就是它的样子:

C:\users\USERFOLDER\下载\

尝试:

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

这只是个骗局,不是解决办法。

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