Question

I got this regex expression from REGEXlib and basically it checks to see if it is a valid UK DVLA Number Plate however i cannot get it to work within JavaScript could some one please help as im not the best with regex as it is.

//On change event for the textbox plate text
function setValue(target){
        var platetext = target.value;
        $('#numberplateyellow').empty();
        $('#numberplatewhite').empty();


        var plateregex = /([A-HJ-PR-Y]{2}([0][1-9]|[1-9][0-9])|[A-HJ-PR-Y]{1}([1-9]|[1-2][0-9]|30|31|33|40|44|55|50|60|66|70|77|80|88|90|99|111|121|123|222|321|333|444|555|666|777|888|999|100|200|300|400|500|600|700|800|900))[ ][A-HJ-PR-Z]{3}$/;

        if (document.platebuilder.target.value.search(plateregex)==-1){

        var answer = window.confirm ("Non LEGAL Plate Detected (YES WE WILL SHOW THE AGREE BOX ONCE I HAVE IT FROM TOM) \n\n Do you understand that this is now classed as a show plate ?");

        if (answer) {
        $('#numberplateyellow').append(platetext);
        $('#numberplatewhite').append(platetext);
        }

      }

}

Thanks

Answer 1

You are mixing jQuery and standard script.

Change var platetext = target.value;

to

var platetext = target.val();

and

if (document.platebuilder.target.value.search(plateregex)==-1){

to

if (!platetext.match(plateregex)) {