JavaScript: RegExp.prototype.test
regex.test(string)
-
Return
true
if regex match part or whole of string, elsefalse
. If there's a global flagg
, repeated call will start fromRegExp.prototype.lastIndex
. [see RegExp Flags]
console.log(/4/.test("345")); // true console.log(/4/.test("999")); // false
Repeated call with global flag.
const gx = /4/g; console.log(gx.lastIndex); // 0 console.log(gx.test("345678")); // true console.log(gx.lastIndex); // 2 console.log(gx.test("345678")); // false console.log(gx.lastIndex); // 0