JavaScript regular expression to check time format

Question

I would like to have a regular expression which clears an HTML field when the input is not correct. I created this one, but instead of clearing the field when it's incorrect, it clears it only when the input is correct.

onchange="this.value=this.value.replace(/^([01]?[0-9]|2[0-3]):[0-5][0-9]/,'')"

I've tried to 'reverse' the code, but it didn't succeed so far.

Answer 1

onchange="if (!this.value.match(/^([01]?[0-9]|2[0-3]):[0-5][0-9]/)) this.value = '';"

Answer 2

if(!/^([01]?[0-9]|2[0-3]):[0-5][0-9]/.test(this.value)) this.value="";

Answer 3

onchange="this.value=
/^([01]?[0-9]|2[0-3]):[0-5][0-9]/.test(this.value) ? this.value : ''"