Question

Hey all I am using Action Script and just simply trying to check if a string contains special characters or numbers, if it does not add it to my list otherwise error output…however the NAN is giving me the error Implicit coercion of a value of type String to an unrelated type Number…any suggestions? here is some code:

private function onAddName(event:Event):void {
        var newItem:Object = {label:addName_ti.text};
        //if not a number true then add onto list.
        if ( isNaN(addName_ti.text )
        {
            names_li.dataProvider.addItem(newItem);
            names_li.dataProvider.sortOn("label");
            addName_ti.text = "";
            addName_bn.enabled = false;
            //User feedback for successfully entering item.
            trace ("Item succesfully added!");
        } else 
        { 
            //User feedback for not succesffully entering item.
            addName_bn.enabled = false;
            trace ("Improper formatting");
        }

    }

Answer 1

isNaN expects a number. That is why you get the error. You should use parseFloat first:

isNaN(parseFloat(addName_ti.text));

parseFloat is good especially for external text, because it will ignore white space and trailing characters. It will return NaN if the parse is unsuccessful.

" 12" would return 12. “12abc” would return 12. “abc12” would return NaN. " 12 34 5 6" would return 12.

If you’re text is guaranteed to be well formatted, the simply casting as a number Number("12") would be slightly faster. In my test, doing it 10 million times was about 400ms quicker.