how to search from end of string in JS

[jasonc]

I have used many versions of code to validate an email in JS but after using it, it fails when another email format shows it face that the code thinks is wrong; but in fact is a valid email.

 

So opted to using this method which would server the purpose I am after but do not know how to search for the seed from the end of the string instead of from the start.

 

here is the code I am wanting to use but not sure how I search for the '.' starting from the end of the string.

 

function checkEmailValid2(email) {
s = email.indexOf(' ') + 1; // is there a space
e = email.indexOf('@') + 1; // find the @
f = email.indexOf('.') + 1; // find the .
	if ( email != '' && s == 0 && e && f > e + 1 && f < email.length) {
		return true;
	} else {
		return false;
	}
}

[sunfighter]

lastIndexOf() in js will tell you the last occurrence position of a character or word in a string.

<script language=javascript>
var emstring = "PUT YOUR EMAIL STRING HERE";
var result = emstring .lastIndexOf(".");

document.write(emstring .length+'<br />'); // This is not needed
document.write(result+'<br />');                  // this tells you where it's at!!!!
</script>

The only gotcha with this is it starts counting from zero, so the very first character will return 0.