Email Validation Javascript

Dynamics CRM has alreaady an inbuilt email address validation mechanism but if you have any custom entity or to do a robust email validation on out-of-the-box fields then you can use the below script.

function validateEmail() {
//replace the attribute used to suit your field
var email = Xrm.Page.getAttribute("emailaddress1").getValue();
if(email != "")
{
  var re = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
      if(re.test(email) == false)
       {
          alert("The email address is invalid");
          Xrm.Page.getAttribute("emailaddress1").setValue("");
        }
   }
}

You can check the video how to add this validation in Dynamics CRM application here.