Regex not working on email domain selection properly

Question

var str = "sdhdhh@gmail.com"; // true but coming false
var str1 = "sdhdhh@gmail.co.uk"; 
var str2 = "sdhdhh@gmail.org";
var str3 = "sdhdhh@gmail.org.uk";
var patt = new RegExp("[a-z0-9._%+-]+@[a-z0-9.-]+?[\.com]?[\.org]?[\.co.uk]?[\.org.uk]$");
console.log( str + " is " + patt.test(str));
console.log( str1 + " is " + patt.test(str1));
console.log( str2 + " is " + patt.test(str2));
console.log( str3 + " is " + patt.test(str3));

Can anyone tell me what is the mistake, my .com example is not working properly

Answer 1

You need

• A grouping construct instead of character classes
• A regex literal notation so that you do not have to double escape special chars
• The ^ anchor at the start of the pattern since you need both ^ and $ to make the pattern match the entire string.

So you need to use

var patt = /^[a-z0-9._%+-]+@[a-z0-9.-]+?(?:\.com|\.org|\.co\.uk|\.org\.uk)$/;

See the regex demo.

If you need to make it case insensitive, add i flag,

var patt = /^[a-z0-9._%+-]+@[a-z0-9.-]+?(?:\.com|\.org|\.co\.uk|\.org\.uk)$/i;