I want to check if a string ends with ab followed by an integer.
Given any string s, how can I first check if it ends with ab1 or ab2 or ab3, and if so, return ab1 or ab2 or ab3.
For example, for string sdfsadfsab2, I want to return ab2.
For string asdfase I want to return empty string.
Is there any regular expression in javascript or jquery can do this? thanks.
The regex you're after could well be:
/ab[0-9]$/ If you want a tester function, that function could look something like this:
function testABInt(string) { var match = string.match(/ab[0-9]$/); return match ? match[0] : ''; } This only matches the end of a string if ab are lower-case chars, and if there is only one int at the end, to match case-insensitive, add the i flag, and/or add a + to match all trailing digits:
/ab[0-9]+$/i 
One way using replace:
str.replace(/.*(ab\d+)$/, "$1"); Another way using match:
(str.match(/ab\d+$/) || [""]).pop(); 
var regex = /([a-zA-Z]{2}[0-9])$/; var str = "sdfsadfsab2"; console.log(str.match(regex)[0]); //outputs "ab2" [a-zA-Z] - a collection of the letters from a-z in lower and upper case{2} - meaning "repeated exactly 2 times"[0-9] - a collection of the digits from 0 to 9$ - meaning "end of the string"Use $ to match the end of the string:
'foo2'.match(/[a-z]{2}\d$/); 
