asp.net中md5加密实现代码

#region 去除HTML标记
/// <summary>
/// 去除HTML标记
/// </summary>
/// <param name="NoHTML">包括HTML的源码 </param>
/// <returns>已经去除后的文字</returns>
public static string NoHTML(string Htmlstring)
{
//删除脚本
Htmlstring = Regex.Replace(Htmlstring, @"<script[^>]*?>.*?</script>", "", RegexOptions.IgnoreCase);
//删除HTML
Htmlstring = Regex.Replace(Htmlstring, @"<(.[^>]*)>", "", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"([rn])[s]+", "", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"-->", "", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"<!--.*", "", RegexOptions.IgnoreCase);

Htmlstring = Regex.Replace(Htmlstring, @"&(quot|#34);", """, RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(amp|#38);", "&", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(lt|#60);", "<", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(gt|#62);", ">", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(nbsp|#160);", " ", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(iexcl|#161);", "xa1", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(cent|#162);", "xa2", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(pound|#163);", "xa3", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&(copy|#169);", "xa9", RegexOptions.IgnoreCase);
Htmlstring = Regex.Replace(Htmlstring, @"&#(d+);", "", RegexOptions.IgnoreCase);

Htmlstring.Replace("<", "");
Htmlstring.Replace(">", "");
Htmlstring.Replace("rn", "");
Htmlstring = HttpContext.Current.Server.HtmlEncode(Htmlstring).Trim();

return Htmlstring;
}
#endregion 

#region 去除非法字串
/// <summary>
/// 去除非法字串
/// </summary>
/// <param name="strChar">原字串</param>
/// <returns>过滤过的字串</returns>
public static string ReplaceBadChar(string strChar)
{
if (strChar.Trim() == "")
{
return "";
}
else
{
strChar = strChar.Replace("'", "");
strChar = strChar.Replace("*", "");
strChar = strChar.Replace("?", "");
strChar = strChar.Replace("(", "");
strChar = strChar.Replace(")", "");
strChar = strChar.Replace("<", "");
strChar = strChar.Replace("=", "");
return strChar.Trim();
}
}
#endregion

#region 检察是否都是数字
/// <summary>
/// 检察是否都是数字
/// </summary>
/// <param name="str">要检查的字串</param>
/// <returns>bool</returns>
public static bool IsNumeric(string str)
{
Regex reg = new Regex(@"^[+]?d*$");
return reg.IsMatch(str);
}
#endregion

#region 检察是否正确的Email格式
/// <summary>
/// 检察是否正确的Email格式
/// </summary>
/// <param name="str">要检查的字串</param>
/// <returns>bool</returns>
public static bool IsEmail(string str)
{
Regex reg = new Regex(@"^([w-.]+)@(([[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.)|(([w-]+.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(]?)$");
return reg.IsMatch(str);
}
#endregion

#region 检察是否正确的日期格式
/// <summary>
/// 检察是否正确的日期格式
/// </summary>
/// <param name="str">要检查的字串</param>
/// <returns>bool</returns>
public static bool IsDate(string str)
{
//考虑到了4年一度的366天，还有特殊的2月的日期
Regex reg = new Regex(@"^((((1[6-9]|[2-9]d)d{2})-(0?[13578]|1[02])-(0?[1-9]|[12]d|3[01]))|(((1[6-9]|[2-9]d)d{2})-(0?[13456789]|1[012])-(0?[1-9]|[12]d|30))|(((1[6-9]|[2-9]d)d{2})-0?2-(0?[1-9]|1d|2[0-8]))|(((1[6-9]|[2-9]d)(0[48]|[2468][048]|[13579][26])|((16|[2468][048]|[3579][26])00))-0?2-29-)) (20|21|22|23|[0-1]?d):[0-5]?d:[0-5]?d$");
return reg.IsMatch(str);
}
#endregion

#region HTML转换为字符串
/// <summary>
/// HTML转换为字符串，转换标识
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string htmToStr(string str)
{
return str.Replace("'", "mySQ;").Replace(""", "myDQ;").Replace("<", "myLt;").Replace(">", "myGt;").Replace("-", "myMl;").Replace("_", "myBl;").Replace("%", "myBs;").Replace("?", "myQe;").Replace("*", "myAl;");
}
#endregion

#region 字符串转换为HTML
/// <summary>
/// 字符串转换为HTML，将还原标识
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string strToHtm(string str)
{
if (str == null) return "";
return str.Replace("mySQ;", "'").Replace("myDQ;", """).Replace("myLt;", "<").Replace("myGt;", ">").Replace("myMl;", "-").Replace("myBl;", "_").Replace("myBs;", "%").Replace("myQe;", "?").Replace("myAl;", "*");
}
#endregion

#region 文本转换为HTML
/// <summary>
/// 文本转换为HTML，更换（n）
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string textToHtm(string str)
{
return str.Replace("t", " ").Replace("<", "<").Replace(">", ">").Replace(" ", " ").Replace("rn", "<br>").Replace("n", "<br>");
}
#endregion

#region 文本转换为输入框内容
/// <summary>
/// 文本转换为输入框内容，
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string HtmToInputValue(string str)
{
//return str.Replace("<","<").Replace(">",">").Replace(""",""").Replace("&","&");
return str.Replace(""", """);
}
#endregion

#region 防Sql注入攻击
/// <summary>
/// 防Sql注入攻击
/// </summary>
/// <param name="strQueryName"></param>
/// <returns></returns>
public static string getQueryString(string strQueryName)
{
//(')(--)(or )(=)
System.Web.HttpRequest myRequest = System.Web.HttpContext.Current.Request;
string str1 = myRequest.QueryString[strQueryName];
if (str1 == null) return "";
str1 = str1.Replace("'", "’").Replace("--", "—").Replace("=", "＝").Replace("or", "o r").Replace("Or", "O r").Replace("OR", "O R").Replace("oR", "o R").Replace(">", "〉").Replace("<", "〈");
return str1;
}
#endregion

#region 防Sql注入攻击
/// <summary>
/// 防Sql注入攻击
/// </summary>
/// <param name="strQueryName"></param>
/// <returns></returns>
public static string getSQLString(string strQueryName)
{
if (strQueryName == null) return "";
strQueryName = strQueryName.Replace("'", "’").Replace("--", "—").Replace("=", "＝").Replace("or", "o r").Replace("Or", "O r").Replace("OR", "O R").Replace("oR", "o R").Replace(">", "〉").Replace("<", "〈");
return strQueryName;
}
#endregion
}