我在遇到类似的问题时遇到过这个问题，只不过我需要检查一个文件或文件夹的路径是否为文件或文件夹，而该文件或文件夹可能实际上并不存在。上面有一些关于答案的评论，提到它们不适用于这种情况。我找到了一个解决方案(我使用VB。NET，但你可以转换，如果你需要)，这似乎很适合我:

Dim path As String = "myFakeFolder\ThisDoesNotExist\"
Dim bIsFolder As Boolean = (IO.Path.GetExtension(path) = "")
'returns True

Dim path As String = "myFakeFolder\ThisDoesNotExist\File.jpg"
Dim bIsFolder As Boolean = (IO.Path.GetExtension(path) = "")
'returns False

希望这能对别人有所帮助!

public bool IsDirectory(string path) {
    return string.IsNullOrEmpty(Path.GetFileName(path)) || Directory.Exists(path);
}

检查路径文件名是否为空字符串，或者目录是否存在。这样就不会出现文件属性错误，同时仍然为可能存在的故障提供冗余。

这是我所能想到的最好的Exists和Attributes属性的行为:

using System.IO;

public static class FileSystemInfoExtensions
{
    /// <summary>
    /// Checks whether a FileInfo or DirectoryInfo object is a directory, or intended to be a directory.
    /// </summary>
    /// <param name="fileSystemInfo"></param>
    /// <returns></returns>
    public static bool IsDirectory(this FileSystemInfo fileSystemInfo)
    {
        if (fileSystemInfo == null)
        {
            return false;
        }

        if ((int)fileSystemInfo.Attributes != -1)
        {
            // if attributes are initialized check the directory flag
            return fileSystemInfo.Attributes.HasFlag(FileAttributes.Directory);
        }

        // If we get here the file probably doesn't exist yet.  The best we can do is 
        // try to judge intent.  Because directories can have extensions and files
        // can lack them, we can't rely on filename.
        // 
        // We can reasonably assume that if the path doesn't exist yet and 
        // FileSystemInfo is a DirectoryInfo, a directory is intended.  FileInfo can 
        // make a directory, but it would be a bizarre code path.

        return fileSystemInfo is DirectoryInfo;
    }
}

下面是测试结果:

    [TestMethod]
    public void IsDirectoryTest()
    {
        // non-existing file, FileAttributes not conclusive, rely on type of FileSystemInfo
        const string nonExistentFile = @"C:\TotallyFakeFile.exe";

        var nonExistentFileDirectoryInfo = new DirectoryInfo(nonExistentFile);
        Assert.IsTrue(nonExistentFileDirectoryInfo.IsDirectory());

        var nonExistentFileFileInfo = new FileInfo(nonExistentFile);
        Assert.IsFalse(nonExistentFileFileInfo.IsDirectory());

        // non-existing directory, FileAttributes not conclusive, rely on type of FileSystemInfo
        const string nonExistentDirectory = @"C:\FakeDirectory";

        var nonExistentDirectoryInfo = new DirectoryInfo(nonExistentDirectory);
        Assert.IsTrue(nonExistentDirectoryInfo.IsDirectory());

        var nonExistentFileInfo = new FileInfo(nonExistentDirectory);
        Assert.IsFalse(nonExistentFileInfo.IsDirectory());

        // Existing, rely on FileAttributes
        const string existingDirectory = @"C:\Windows";

        var existingDirectoryInfo = new DirectoryInfo(existingDirectory);
        Assert.IsTrue(existingDirectoryInfo.IsDirectory());

        var existingDirectoryFileInfo = new FileInfo(existingDirectory);
        Assert.IsTrue(existingDirectoryFileInfo.IsDirectory());

        // Existing, rely on FileAttributes
        const string existingFile = @"C:\Windows\notepad.exe";

        var existingFileDirectoryInfo = new DirectoryInfo(existingFile);
        Assert.IsFalse(existingFileDirectoryInfo.IsDirectory());

        var existingFileFileInfo = new FileInfo(existingFile);
        Assert.IsFalse(existingFileFileInfo.IsDirectory());
    }

这是我的:

    bool IsPathDirectory(string path)
    {
        if (path == null) throw new ArgumentNullException("path");
        path = path.Trim();

        if (Directory.Exists(path)) 
            return true;

        if (File.Exists(path)) 
            return false;

        // neither file nor directory exists. guess intention

        // if has trailing slash then it's a directory
        if (new[] {"\\", "/"}.Any(x => path.EndsWith(x)))
            return true; // ends with slash

        // if has extension then its a file; directory otherwise
        return string.IsNullOrWhiteSpace(Path.GetExtension(path));
    }

这与别人的答案相似，但并不完全相同。

我明白了，我迟到了10年。 我面临的情况是，从某些属性中，我可以接收文件名或完整的文件路径。如果没有提供路径，我必须通过附加由另一个属性提供的“全局”目录路径来检查文件的存在性。

对我来说

var isFileName = System.IO.Path.GetFileName (str) == str;

成功了。 好吧，这不是魔法，但也许这可以为某人节省几分钟的思考时间。 因为这只是一个字符串解析，所以带点的diri -names可能会给出假阳性…

如果你想找到目录，包括那些标记为“hidden”和“system”的目录，试试这个(需要。net V4):

FileAttributes fa = File.GetAttributes(path);
if(fa.HasFlag(FileAttributes.Directory))