移除文件的只读属性

怎样只移除Readonly属性呢? 因为有很多属性还是很有用的，比如说加密，存档，等等。所以有的时候只需要移除只读属性。 移除只读属性的代码如下：

using System;
using System.IO;
using System.Text;
class Test 
{
    public static void Main() 
    {
        string path = @"c:\temp\MyTest.txt";

        // Create the file if it exists.
        if (!File.Exists(path)) 
        {
            File.Create(path);
        }

        FileAttributes attributes = File.GetAttributes(path);

        if ((attributes & FileAttributes.ReadOnly) == FileAttributes.ReadOnly)
        {
            // Make the file RW
            attributes = RemoveAttribute(attributes, FileAttributes.ReadOnly);
            File.SetAttributes(path, attributes);
            Console.WriteLine("The {0} file is no longer RO.", path);
        } 
        else 
        {
            // Make the file RO
            File.SetAttributes(path, File.GetAttributes(path) | FileAttributes.Hidden);
            Console.WriteLine("The {0} file is now RO.", path);
        }
    }

    private static FileAttributes RemoveAttribute(FileAttributes attributes, FileAttributes attributesToRemove)
    {
        return attributes & ~attributesToRemove;
    }
}

From:http://stackoverflow.com/questions/7399611/how-to-remove-readonly-attribute-from-a-file