parameterCheck.cs 
public class parameterCheck...{ 
public static bool isEmail(string emailString)...{ 
return System.Text.RegularExpressions.Regex.IsMatch(emailString, "['\\w_-]+(\\. ['\\w_-]+)*@['\\w_-]+(\\.['\\w_-]+)*\\.[a-zA-Z]...{2,4}"); 
} public static bool isInt(string intString)...{ return System.Text.RegularExpressions.Regex.IsMatch(intString ,"^(\\d...{5}-\\d{4})| (\\d...{5})$"); } public static bool isUSZip(string zipString)...{ return System.Text.RegularExpressions.Regex.IsMatch(zipString ,"^-[0-9]+$|^[0-9] +$"); 
} protected void Application_BeginRequest(Object sender, EventArgs e){ String[] safeParameters = System.Configuration.ConfigurationSettings.AppSettings ["safeParameters"].ToString().Split(','); for(int i= 0 ;i < safeParameters.Length; i++)...{ String parameterName = safeParameters[i].Split('-')[0]; String parameterType = safeParameters[i].Split('-')[1]; isValidParameter(parameterName, parameterType); } } public void isValidParameter(string parameterName, string parameterType)...{ string parameterValue = Request.QueryString[parameterName]; if(parameterValue == null) return; if(parameterType.Equals("int32"))...{ if(!parameterCheck.isInt(parameterValue)) Response.Redirect("parameterError.aspx"); } else if (parameterType.Equals("double"))...{ if(!parameterCheck.isDouble(parameterValue)) Response.Redirect("parameterError.aspx"); } else if (parameterType.Equals("USzip"))...{ if(!parameterCheck.isUSZip(parameterValue)) Response.Redirect("parameterError.aspx"); } else if (parameterType.Equals("email"))...{ if(!parameterCheck.isEmail(parameterValue)) Response.Redirect("parameterError.aspx"); } }