我过去在这方面取得过成功。

漂亮，短，静态:-)

    public static string returnSafeString(string s)
    {
        foreach (char character in Path.GetInvalidFileNameChars())
        {
            s = s.Replace(character.ToString(),string.Empty);
        }

        foreach (char character in Path.GetInvalidPathChars())
        {
            s = s.Replace(character.ToString(), string.Empty);
        }

        return (s);
    }

如果您将目录和文件名附加在一起并对其进行消毒，而不是分别对它们进行消毒，那么您的代码将更加干净。至于清除:，只需取字符串中的第二个字符。如果它等于"replacechar"，用冒号替换它。由于这个应用程序是为您自己使用，这样的解决方案应该是完全足够的。

我认为问题在于你先给Path打电话。GetDirectoryName在坏字符串上。如果其中包含非文件名字符，. net就无法判断字符串的哪些部分是目录和抛出。你必须做字符串比较。

假设只有文件名有问题，而不是整个路径，试试这个:

public static string SanitizePath(string path, char replaceChar)
{
    int filenamePos = path.LastIndexOf(Path.DirectorySeparatorChar) + 1;
    var sb = new System.Text.StringBuilder();
    sb.Append(path.Substring(0, filenamePos));
    for (int i = filenamePos; i < path.Length; i++)
    {
        char filenameChar = path[i];
        foreach (char c in Path.GetInvalidFileNameChars())
            if (filenameChar.Equals(c))
            {
                filenameChar = replaceChar;
                break;
            }

        sb.Append(filenameChar);
    }

    return sb.ToString();
}

我希望以某种方式保留字符，而不仅仅是简单地用下划线替换字符。

我想到的一种方法是用类似的字符替换这些字符(在我的情况下)，不太可能被用作常规字符。所以我从无效字符列表中找到了类似字符。

下面是使用look-a-like进行编码和解码的函数。

这段代码不包括所有System.IO.Path.GetInvalidFileNameChars()字符的完整列表。因此，扩展或使用下划线替换任何剩余字符由您自己决定。

private static Dictionary<string, string> EncodeMapping()
{
    //-- Following characters are invalid for windows file and folder names.
    //-- \/:*?"<>|
    Dictionary<string, string> dic = new Dictionary<string, string>();
    dic.Add(@"\", "Ì"); // U+OOCC
    dic.Add("/", "Í"); // U+OOCD
    dic.Add(":", "¦"); // U+00A6
    dic.Add("*", "¤"); // U+00A4
    dic.Add("?", "¿"); // U+00BF
    dic.Add(@"""", "ˮ"); // U+02EE
    dic.Add("<", "«"); // U+00AB
    dic.Add(">", "»"); // U+00BB
    dic.Add("|", "│"); // U+2502
    return dic;
}

public static string Escape(string name)
{
    foreach (KeyValuePair<string, string> replace in EncodeMapping())
    {
        name = name.Replace(replace.Key, replace.Value);
    }

    //-- handle dot at the end
    if (name.EndsWith(".")) name = name.CropRight(1) + "°";

    return name;
}

public static string UnEscape(string name)
{
    foreach (KeyValuePair<string, string> replace in EncodeMapping())
    {
        name = name.Replace(replace.Value, replace.Key);
    }

    //-- handle dot at the end
    if (name.EndsWith("°")) name = name.CropRight(1) + ".";

    return name;
}

你可以选择自己喜欢的样子。我使用windows中的字符地图应用程序来选择我的%windir%\system32\charmap.exe

当我通过发现进行调整时，我将更新这段代码。

基于Andre的精彩回答，并考虑到Spud对保留词的评论，我做出了这样的版本:

/// <summary>
/// Strip illegal chars and reserved words from a candidate filename (should not include the directory path)
/// </summary>
/// <remarks>
/// http://stackoverflow.com/questions/309485/c-sharp-sanitize-file-name
/// </remarks>
public static string CoerceValidFileName(string filename)
{
    var invalidChars = Regex.Escape(new string(Path.GetInvalidFileNameChars()));
    var invalidReStr = string.Format(@"[{0}]+", invalidChars);

    var reservedWords = new []
    {
        "CON", "PRN", "AUX", "CLOCK$", "NUL", "COM0", "COM1", "COM2", "COM3", "COM4",
        "COM5", "COM6", "COM7", "COM8", "COM9", "LPT0", "LPT1", "LPT2", "LPT3", "LPT4",
        "LPT5", "LPT6", "LPT7", "LPT8", "LPT9"
    };

    var sanitisedNamePart = Regex.Replace(filename, invalidReStr, "_");
    foreach (var reservedWord in reservedWords)
    {
        var reservedWordPattern = string.Format("^{0}\\.", reservedWord);
        sanitisedNamePart = Regex.Replace(sanitisedNamePart, reservedWordPattern, "_reservedWord_.", RegexOptions.IgnoreCase);
    }

    return sanitisedNamePart;
}

这些是单元测试

[Test]
public void CoerceValidFileName_SimpleValid()
{
    var filename = @"thisIsValid.txt";
    var result = PathHelper.CoerceValidFileName(filename);
    Assert.AreEqual(filename, result);
}

[Test]
public void CoerceValidFileName_SimpleInvalid()
{
    var filename = @"thisIsNotValid\3\\_3.txt";
    var result = PathHelper.CoerceValidFileName(filename);
    Assert.AreEqual("thisIsNotValid_3__3.txt", result);
}

[Test]
public void CoerceValidFileName_InvalidExtension()
{
    var filename = @"thisIsNotValid.t\xt";
    var result = PathHelper.CoerceValidFileName(filename);
    Assert.AreEqual("thisIsNotValid.t_xt", result);
}

[Test]
public void CoerceValidFileName_KeywordInvalid()
{
    var filename = "aUx.txt";
    var result = PathHelper.CoerceValidFileName(filename);
    Assert.AreEqual("_reservedWord_.txt", result);
}

[Test]
public void CoerceValidFileName_KeywordValid()
{
    var filename = "auxillary.txt";
    var result = PathHelper.CoerceValidFileName(filename);
    Assert.AreEqual("auxillary.txt", result);
}

我过去在这方面取得过成功。

漂亮，短，静态:-)

    public static string returnSafeString(string s)
    {
        foreach (char character in Path.GetInvalidFileNameChars())
        {
            s = s.Replace(character.ToString(),string.Empty);
        }

        foreach (char character in Path.GetInvalidPathChars())
        {
            s = s.Replace(character.ToString(), string.Empty);
        }

        return (s);
    }