在javascript常规模式中包含变量

Question

I have a in javascript var num = "x" , How do i include this as part of a regular pattern:

var pattern = /"i want to include the variable num here"/i

If i was working with a string this would have been something like"

var str = ""+num+"";

Answer 1

You can user RegExp for that.

var num = "x";
var strToCheck = "string x here";
var pattern = new RegExp(num, 'i');
var testResult = pattern.test(strToCheck);