將用戶輸入的字符串轉換爲可換行、替換Html編碼、無危害數據庫特殊字符、去掉首尾空白、的安全方便代碼

public static string ConvertStr(string inputString)
        {
            string retVal = inputString;
            retVal = retVal.Replace("&", "&");
            retVal = retVal.Replace("/"", """);
            retVal = retVal.Replace("<", "&lt;");
            retVal = retVal.Replace(">", "&gt;");
            retVal = retVal.Replace(" ", "&nbsp;");
            retVal = retVal.Replace("  ", "&nbsp;&nbsp;");
            retVal = retVal.Replace("/t", "&nbsp;&nbsp;");
            retVal = retVal.Replace("/r", "<br>");
            return retVal;
        }

        private static string FetchURL(string strMessage)
        {
            string strPattern = @"(?<url>(http|ftp|mms|rstp|news|https)://(?:[/w-]+/.)+[/w-]+(?:/[/w-./?%&~=]*[^./s|,|/)|<|!])?)";
            string strReplace = "<a href=/"${url}/" target=_blank>${url}</a>";
            string strInput = strMessage;
            string strResult;
            strResult = Regex.Replace(strInput, strPattern, strReplace);
            strPattern = @"(?<!http://)(?<url>www/.(?:[/w-]+/.)+[/w-]+(?:/[/w-./?%&~=]*[^./s|,|/)|<|!])?)";
            strReplace = "<a href=/"http://${url}/" target=_blank>${url}</a>";
            strResult = Regex.Replace(strResult, strPattern, strReplace);
            return strResult;
        } 

        public string ToUrl(string inputString)
        {
            string retVal = inputString;
            retVal = ConvertStr(retVal);
            retVal = FetchURL(retVal);
            return retVal;
        }