function validate_form()
{
	var var1=document.getElementById('name').value;
	var var2=document.getElementById('phone').value;
	var var3=document.getElementById('address').value;
	var var4=document.getElementById('email').value;
	
		if(var1.length!=0 && var2.length!=0 && var3.length!=0 && var4.length!=0 )
		{
			if(echeck(var4)==false)
					return false;
					else
					return true;
		}
		else
   		{
   		if(var1.length==0)
   		alert('Please enter the name!');
   		else if(var2.length==0)
   		alert('Please enter the phone!');
   		else if(var3.length==0)
   		alert('Please enter the address!');
   		else if(var4.length==0)
   		alert('Please enter the email!');
   		
   		return false;
   		}
	
}


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;					
	}