function echeck(str){
		var at="@";
		var dot=".";
		var lat=str.indexOf(at);
		var lstr=str.length;
		var ldot=str.indexOf(dot);
		if (str.indexOf(at)==-1){
		   alert("Invalid E-mail ID");
		   return false;
		}
		if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
		   alert("Invalid E-mail ID");
		   return false;
		}
		if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
		    alert("Invalid E-mail ID");
		    return false;
		}
		 if (str.indexOf(at,(lat+1))!=-1){
		    alert("Invalid E-mail ID");
		    return false;
		 }
		 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
		    alert("Invalid E-mail ID");
		    return false;
		 }
		 if (str.indexOf(dot,(lat+2))==-1){
		    alert("Invalid E-mail ID");
		    return false;
		 }
		 if (str.indexOf(" ")!=-1){
		    alert("Invalid E-mail ID");
		    return false;
		 }
 		 return true;
	}
function ValidateForm(formname){

var phonenum=document.sendemail.phone.value;
var zipnum=document.sendemail.zipcode.value;

    var friendemailID=document.sendemail.ename;
    
    if (document.sendemail.fname.value ==""){
        alert("Please enter your First Name");
        document.sendemail.fname.focus();
        return false;
    }
if (document.sendemail.lname.value ==""){
        alert("Please enter your Last Name");
        document.sendemail.lname.focus();
        return false;
    }
if (document.sendemail.cname.value ==""){
        alert("Please enter your Company Name");
        document.sendemail.cname.focus();
        return false;
    }

if (document.sendemail.cityname.value ==""){
        alert("Please enter your City");
        document.sendemail.cityname.focus();
        return false;
    }
if (document.sendemail.zipcode.value ==""){
        alert("Please enter your city Zipcode");
        document.sendemail.zipcode.focus();
        return false;
    }
if(checknumber(zipnum)==false){

        document.sendemail.zipcode.value="";
        document.sendemail.zipcode.focus();
        return false;

      }
if ((friendemailID.value==null)||(friendemailID.value=="")){
		alert("Please enter Valid Email ID");
		friendemailID.focus();
		return false;
	}
	if (echeck(friendemailID.value)==false){
		friendemailID.value="";
		friendemailID.focus();
		return false;
	}
 
if (document.sendemail.hidden_string.value !=document.sendemail.img1.value){
        alert("Wrong Verification Code");
        document.sendemail.img1.focus();
        return false;
    }    
	return true
 }

function checknumber(checknum){
var x=checknum;
var anum=/(^\d+$)|(^\d+\.\d+$)/
if (anum.test(x))
return true;
else{
alert("Please input a valid number!")
return false;
}
}