Javascript in asp.net

1. For Email- Validation.
   function email()
   {
   src = document.form1.Email.value;
   var emailReg = "^[\\w-_\.]*[\\w-_\.]\@[\\w]\.+[\\w]+[\\w]$";
   var regex = new RegExp(emailReg);
   var c = regex.test(src);
   if(c == false && src !="" )
   {
   alert("Please Enter valid email address");
   document.form1.Email.select();
   }
   }
2. For Postalcode validation.
   function PostalCodes()
   {
   var poscod =document.form1.PostalCode.value;
   var lenpcod = poscod.length;
   if(isNaN(poscod) lenpcod!=6 && poscod!="")
   {
   alert("Enter valid Postal Code");
   document.form1.PostalCode.select();
   }
   }
3. For All Field should not be Blank.
   function chkerr(f,chkval){
   var chkvalarr = chkval.split(",");
   var totform = document.forms.length;
   for(var fm=0;fmfor(var i=0;ifor(var j=0;j<=chkvalarr.length;j++){
   if(document.forms[fm].elements[i].value == "" && document.forms[fm].elements[i].name == chkvalarr[j]){
   alert(document.forms[fm].elements[i].name +" Should not blank");
   document.forms[fm].elements[i].focus();
   document.forms[fm].elements[i].style.background="lightyellow";
   return false;
   }
   }
   }
   }
   }
4. For Year Validation .
   function yr()
   {
   var flag = 0;
   var yea = document.form1.Year.value;
   var mnth = document.form1.Month.value;
   var dt = document.form1.Day.value;
   var len = yea.length;
   if(yea!="")
   {
   if(yea%400==0 yea%100==0 yea%4==0)
   {
   flag=1;
   }
   if((!isNaN(yea) && len ==4))
   {
   if(mnth==2)
   {
   if(flag==1)
   {
   if(dt>29)
   {
   alert("Invalid Day");
   document.form1.Day.select();
   return false;
   }
   }
   else
   {
   if(dt>28)
   {
   alert("Invalid Day");
   document.form1.Day.select();
   }
   }
   }
   }
   else
   {
   alert("Invalid Year");
   document.form1.Year.select();
   }
   }
   }
5. For Date Validation.
   function dt()
   {
   var day = document.form1.Day.value;
   var mnth = document.form1.Month.value;
   var len = day.length;
   var flag=0;
   if(mnth == 1 mnth == 3 mnth == 5 mnth == 7 mnth == 8 mnth == 10 mnth == 12)
   {
   flag = 1;
   }
   else
   {
   flag = 0;
   }
   if(flag==1)
   {
   if((isNaN(day) && day!="") ( len>2 && day!="") ( day >31 && day!="") (mnth==2 && day >29 && day!="" ) )
   {
   alert("Enter Valid Day");
   document.form1.Day.select();
   return false;
   }
   }
   else if(flag==0)
   {
   if((isNaN(day) && day!="") ( len>2 && day!="") ( day >30 && day!="") (mnth==2 && day >29 && day!="" ) )
   {
   alert("Enter Valid Day");
   document.form1.Day.select();
   return false;
   }
   }
   }
   function PostalCodes()
   {
   var poscod =document.form1.PostalCode.value;
   var lenpcod = poscod.length;
   if(isNaN(poscod) lenpcod!=6 && poscod!="")
   {
   alert("Enter valid Postal Code");
   document.form1.PostalCode.select();
   }
   }
6. For Chaking From DB Whether Email is aveleble or not.
   function emailavil()
   {
   var ema = document.form1.Email.value;
   sndUserCheck(ema);
   }

// Include Followin js file for checking from db;
// JScript File
var ajax;
function MyObject(){
if(window.XMLHttpRequest)
{
ajax = new XMLHttpRequest();
}
else if(window.ActiveXObject)
{
ajax = new ActiveXObject("Microsoft.XMLHTTP");
}else {
ajax = new ActiveXObject("MSXML2.XMLHTTP");
}
return ajax;
}
function handelResponse(){
var serverres;
if (ajax.readyState== 4) {
if (ajax.status== 200) {
serverres = ajax.responseText;
alert(serverres.substr(0,15));
}
}
}
function sndUserCheck(action)
{
MyObject();
ajax.open("GET","Default.aspx?t1="+action,true);
ajax.onreadystatechange = handelResponse;
ajax.send(null);
}

// c# part.

SqlConnection conn;
SqlCommand cmd;
string email = Request.QueryString.Get("t1");
if (email != null)
{
conn = new SqlConnection(ConfigurationManager.ConnectionStrings["ExamConnectionString"].ConnectionString);
cmd = new SqlCommand("select count(*) from UserMaster where EmailID='" + email + "'",conn);
conn.Open();
int count = (int)cmd.ExecuteScalar();
if (count > 0)
{
Response.Write("Not Availeble");
}
else
{
Response.Write("Availeble");
}
conn.Close();
}

}