欢迎大家来重构一下微软的这段代码

    下面这段代码是从.NET Framework 2.0 beta2中弄出来的，看后除了大为faint外，真的是没有语言了，虽然作者还是考虑了不少的优化。欢迎大家来重构一下这段代码:) 这个方法的功能是把JScript字符串转换为文本形式，也就是把一些特殊的字符转意一下。

internal static string QuoteJScriptString(string value, bool forUrl);
 
Declaring Type: System.Web.UI.Util 
Assembly: System.Web, Version=2.0.0.0 

public static string QuoteJScriptString(string value, bool forUrl)
{
    StringBuilder strbQuoted = null;
    if (StringHelper.IsEmpty(value))
    {
        return string.Empty;
    }
    int oldIndex = 0;
    int walkCount = 0;
    for (int i = 0; i < value.Length; i++)
    {
        char ch = value[i];
        if  ( ch <= '"' )
        {
            switch (ch)
            {
                case '\t':
                {
                    if (strbQuoted == null)
                    {
                        strbQuoted = new StringBuilder(value.Length + 5);
                    }
                    if (walkCount > 0)
                    {
                        strbQuoted.Append(value, oldIndex, walkCount);
                    }
                    strbQuoted.Append(@"\t");
                    oldIndex = i + 1;
                    walkCount = 0;
                    break;
                }
                case '\n':
                {
                    if (strbQuoted == null)
                    {
                        strbQuoted = new StringBuilder(value.Length + 5);
                    }
                    if (walkCount > 0)
                    {
                        strbQuoted.Append(value, oldIndex, walkCount);
                    }
                    strbQuoted.Append(@"\n");
                    oldIndex = i + 1;
                    walkCount = 0;
                    break;
                }
                case '\v':
                case '\f':
                {
                    walkCount++;
                    break;
                }
                case '\r':
                {
                    if (strbQuoted == null)
                    {
                        strbQuoted = new StringBuilder(value.Length + 5);
                    }
                    if (walkCount > 0)
                    {
                        strbQuoted.Append(value, oldIndex, walkCount);
                    }
                    strbQuoted.Append(@"\r");
                    oldIndex = i + 1;
                    walkCount = 0;
                    break;
                }
                case '"':
                {
                    if (strbQuoted == null)
                    {
                        strbQuoted = new StringBuilder(value.Length + 5);
                    }
                    if (walkCount > 0)
                    {
                        strbQuoted.Append(value, oldIndex, walkCount);
                    }
                    strbQuoted.Append("\\\"");
                    oldIndex = i + 1;
                    walkCount = 0;
                    break;
                }
                default:
                {
                    walkCount++;
                    break;
                }
            }
        }
        else
        {
            switch (ch)
            {
                case '%':
                {
                    if (!forUrl)
                    {
                        walkCount++;
                        break;
                    }
                    if (strbQuoted == null)
                    {
                        strbQuoted = new StringBuilder(value.Length + 6);
                    }
                    if (walkCount > 0)
                    {
                        strbQuoted.Append(value, oldIndex, walkCount);
                    }
                    strbQuoted.Append("%25");
                    oldIndex = i + 1;
                    walkCount = 0;
                    break;
                }
                case '&':
                {
                    walkCount++;
                    break;
                }
                case '\'':
                {
                    if (strbQuoted == null)
                    {
                        strbQuoted = new StringBuilder(value.Length + 5);
                    }
                    if (walkCount > 0)
                    {
                        strbQuoted.Append(value, oldIndex, walkCount);
                    }
                    strbQuoted.Append(@"\'");
                    oldIndex = i + 1;
                    walkCount = 0;
                    break;
                }
                case '\\':
                {
                    if (strbQuoted == null)
                    {
                        strbQuoted = new StringBuilder(value.Length + 5);
                    }
                    if (walkCount > 0)
                    {
                        strbQuoted.Append(value, oldIndex, walkCount);
                    }
                    strbQuoted.Append(@"\\");
                    oldIndex = i + 1;
                    walkCount = 0;
                    break;
                }
                default:
                {
                    walkCount++;
                    break;
                }
            }
        }
    }
    if (strbQuoted == null)
    {
        return value;
    }
    if (walkCount > 0)
    {
        strbQuoted.Append(value, oldIndex, walkCount);
    }
    return strbQuoted.ToString();
}

    // 看后是不是感到明白了微软为什么恐惧OpenSource?!