参数按照ASCII码从小到大排序

public static void requestPay()
{
Dictionary<string,string> dics = new Dictionary<string,string>();
dics.Add("amount",amount);
dics.Add("callback_url",callback_url);
dics.Add("goodsname",goodsname);
dics.Add("merchno",merchno);
dics.Add("notify_url",notify_url);
dics.Add("ordno",ordno);
dics.Add("organno",organno);
dics.Add("version",version);
dics.Add("paytype",paytype);

getParamSrc(dics);
}

public static String getParamSrc(Dictionary<string,string> paramsMap)
{
var vDic = (from objDic in paramsMap orderby objDic.Key ascending select objDic);
StringBuilder str = new StringBuilder();
foreach (KeyValuePair<string,string> kv in vDic)
{
string pkey = kv.Key;
string pvalue = kv.Value;
str.Append(pkey + "=" + pvalue + "&");
}

String result = str.ToString().Substring(0,str.ToString().Length - 1); return result;}