unity3d：http www get传输中文与空格

IEnumerator Post()
    {
        WWWForm form = new WWWForm();
        form.AddField(UrlEncode("123 qwe"), UrlEncode("123 sdfsdf"));
        form.AddField(UrlEncode("num2"), UrlEncode("sdf 阿斯顿发生单号"));
        WWW www = new WWW("http://" + PublicFunc.GetIp() + ":" + m_port + "/", form);
        Debug.Log(www.url);
        yield return www;
        Debug.Log(www.text);
    }

    public static string UrlEncode(string str)
    {
        string sb = "";
        byte[] byStr = System.Text.Encoding.UTF8.GetBytes(str);
        for (int i = 0; i < byStr.Length; i++)
        {
            if (i == 0)
            {
                sb += byStr[i].ToString();
            }
            else
            {
                sb += "%" + byStr[i].ToString();
            }
        }
        return sb;
    }

public static string UrlDecode(string str)
        {
            string[] chars = Regex.Split(str, "%25", RegexOptions.IgnoreCase);
            byte[] b = new byte[chars.Length];

            for (int i = 0; i < chars.Length; i++)
            {
                b[i] = (byte)(int.Parse(chars[i]));
            }
            //按照指定编码将字节数组变为字符串
            return System.Text.Encoding.UTF8.GetString(b);
        }