how can i check multiple patterns with RegExp in Javascript?

Question

I want to make sure that the email address entered by the user contains @ and . using RegExp.

This is my code:

var patt = new RegExp("@");
var pattresult = patt.test(document.getElementById("email").value);
if (pattresult != true){
    errMsg += "Enter a valid Email Address.";
    result = false;
}

Working fine so far only for @. How can I add . in the same pattern?

Answer 1

Try this, I have tested it.

var mail=document.getElementById("email").value;  
var filter = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
if (!filter.test(mail) && mail!="") 
{
    alert('Enter a valid Email Address.')
}