我需要一个强大的和简单的方法来删除非法的路径和文件字符从一个简单的字符串。我已经使用了下面的代码,但它似乎没有做任何事情,我错过了什么?

using System;
using System.IO;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            string illegal = "\"M<>\"\\a/ry/ h**ad:>> a\\/:*?\"<>| li*tt|le|| la\"mb.?";

            illegal = illegal.Trim(Path.GetInvalidFileNameChars());
            illegal = illegal.Trim(Path.GetInvalidPathChars());

            Console.WriteLine(illegal);
            Console.ReadLine();
        }
    }
}

当前回答

上面的大多数解决方案都将路径和文件名的非法字符组合在一起,这是错误的(即使两个调用当前返回相同的字符集)。我将首先在path和filename中分割path+filename,然后应用适当的集,如果它们,然后再次结合两者。

wvd_vegt

其他回答

文件名:

var cleanFileName = string.Join("", fileName.Split(Path.GetInvalidFileNameChars()));

对于全路径:

var cleanPath = string.Join("", path.Split(Path.GetInvalidPathChars()));

请注意,如果打算将此作为安全特性使用,更健壮的方法是展开所有路径,然后验证用户提供的路径确实是用户应该访问的目录的子目录。

我写这个怪物是为了好玩,它让你可以往返:

public static class FileUtility
{
    private const char PrefixChar = '%';
    private static readonly int MaxLength;
    private static readonly Dictionary<char,char[]> Illegals;
    static FileUtility()
    {
        List<char> illegal = new List<char> { PrefixChar };
        illegal.AddRange(Path.GetInvalidFileNameChars());
        MaxLength = illegal.Select(x => ((int)x).ToString().Length).Max();
        Illegals = illegal.ToDictionary(x => x, x => ((int)x).ToString("D" + MaxLength).ToCharArray());
    }

    public static string FilenameEncode(string s)
    {
        var builder = new StringBuilder();
        char[] replacement;
        using (var reader = new StringReader(s))
        {
            while (true)
            {
                int read = reader.Read();
                if (read == -1)
                    break;
                char c = (char)read;
                if(Illegals.TryGetValue(c,out replacement))
                {
                    builder.Append(PrefixChar);
                    builder.Append(replacement);
                }
                else
                {
                    builder.Append(c);
                }
            }
        }
        return builder.ToString();
    }

    public static string FilenameDecode(string s)
    {
        var builder = new StringBuilder();
        char[] buffer = new char[MaxLength];
        using (var reader = new StringReader(s))
        {
            while (true)
            {
                int read = reader.Read();
                if (read == -1)
                    break;
                char c = (char)read;
                if (c == PrefixChar)
                {
                    reader.Read(buffer, 0, MaxLength);
                    var encoded =(char) ParseCharArray(buffer);
                    builder.Append(encoded);
                }
                else
                {
                    builder.Append(c);
                }
            }
        }
        return builder.ToString();
    }

    public static int ParseCharArray(char[] buffer)
    {
        int result = 0;
        foreach (char t in buffer)
        {
            int digit = t - '0';
            if ((digit < 0) || (digit > 9))
            {
                throw new ArgumentException("Input string was not in the correct format");
            }
            result *= 10;
            result += digit;
        }
        return result;
    }
}

抛出异常。

if ( fileName.IndexOfAny(Path.GetInvalidFileNameChars()) > -1 )
            {
                throw new ArgumentException();
            }

我认为使用正则表达式验证并指定允许哪些字符要容易得多,而不是试图检查所有坏字符。 请看这些链接: http://www.c-sharpcorner.com/UploadFile/prasad_1/RegExpPSD12062005021717AM/RegExpPSD.aspx http://www.windowsdevcenter.com/pub/a/oreilly/windows/news/csharp_0101.html

另外,搜索一下“正则表达式编辑器”,它们很有帮助。有一些甚至可以为你输出c#代码。

这样做会想要你想要的,避免碰撞

 static string SanitiseFilename(string key)
    {
        var invalidChars = Path.GetInvalidFileNameChars();
        var sb = new StringBuilder();
        foreach (var c in key)
        {
            var invalidCharIndex = -1;
            for (var i = 0; i < invalidChars.Length; i++)
            {
                if (c == invalidChars[i])
                {
                    invalidCharIndex = i;
                }
            }
            if (invalidCharIndex > -1)
            {
                sb.Append("_").Append(invalidCharIndex);
                continue;
            }

            if (c == '_')
            {
                sb.Append("__");
                continue;
            }

            sb.Append(c);
        }
        return sb.ToString();

    }