Javascript检测按键键码不可打印的键

Question

    this.inputText.on('keypress', function(e){
        if ( String.fromCharCode(e.keyCode)) { //or e.keyCode == ""
            valid = true;
            console.log(true);
        } else {
            valid = false;
            console.log(false);
        }
   });

I try to detect when keypress, key is printable key (unprintable key - like ctrl + a, or arrow up)

but It never return fasle when I press unprintable key, like arrow down

anyone know how to achieve this?

Answer 1

Use keydown , not keypress . The whole point of keypress is that it's for keys that result in a printable character.