C#字串与Unicode互相转换方法

/// <summary>
/// 将原始字串转换为unicode,格式为\u....\u....
/// </summary>
/// <param name="srcText"></param>
/// <returns></returns>
private string StringToUnicode(string srcText)
{
string dst = "";
char[] src = srcText.ToCharArray();
for (int i = 0; i < src.Length; i++)
{
byte[] bytes = Encoding.Unicode.GetBytes(src[i].ToString());
string str = @"\u" + bytes[1].ToString("X2") + bytes[0].ToString("X2");
dst += str;
}
return dst;
}

/// <summary>
/// 将Unicode字串\u....\u....格式字串转换为原始字符串
/// </summary>
/// <param name="srcText"></param>
/// <returns></returns>
private string UnicodeToString(string srcText)
{
string dst = "";
string src = srcText;
int len = srcText.Length / 6;

for (int i = 0; i <= len - 1; i++)
{
string str = "";
str = src.Substring(0, 6).Substring(2);
src = src.Substring(6);
byte[] bytes = new byte[2];
bytes[1] = byte.Parse(int.Parse(str.Substring(0, 2), NumberStyles.HexNumber).ToString());
bytes[0] = byte.Parse(int.Parse(str.Substring(2, 2), NumberStyles.HexNumber).ToString());
dst += Encoding.Unicode.GetString(bytes);
}
return dst;
}

string aa = QConnectSDK.CustomWebRequest.getResponse("http://192.168.28.64:1000/", QConnectSDK.Method.GET, null).Replace("charset=gb2312", "charset=utf-8");
//string utfStr = GB2312ToUtf8(aa);
using (System.IO.StreamWriter sw = new System.IO.StreamWriter(Server.MapPath("~/2.htm"), false, Encoding.UTF8))
{
sw.Write(aa);
}
}
public string GB2312ToUtf8(string gb2312String)
{
Encoding fromEncoding = Encoding.GetEncoding("gb2312");
Encoding toEncoding = Encoding.UTF8;
return EncodingConvert(gb2312String, fromEncoding, toEncoding);
}

public string Utf8ToGB2312(string utf8String)
{
Encoding fromEncoding = Encoding.UTF8;
Encoding toEncoding = Encoding.GetEncoding("gb2312");
return EncodingConvert(utf8String, fromEncoding, toEncoding);
}

public string EncodingConvert(string fromString, Encoding fromEncoding, Encoding toEncoding)
{
byte[] fromBytes = fromEncoding.GetBytes(fromString);
byte[] toBytes = Encoding.Convert(fromEncoding, toEncoding, fromBytes);

string toString = toEncoding.GetString(toBytes);
return toString;
}