javascript onkeypressed not giving current text box content

I have an html form like this:

<form id="boxy" action="layout.html" method="get" accept-charset="utf-8">
  <input type="text" id="a" onkeypress="Boxy.Check(this);">
</form>

Invoking javascript like this:

Boxy.Check = function() {
    input = document.getElementById(this.currentSelector.id).value;
    console.log("\"" + input + "\"");
};

However, this.value is the previous开发者_C百科 value before onkeypress.

For example, if I just type "A" into the form, console.log() prints "". And if I type "AA", console.log prints "A".

Is there a way to get the current content of the input?

I think you need to use onkeyup.

var KeyID = (window.event) ? event.keyCode : e.keyCode;

values for KeyID are:

> 16 (Shift)
> 17 (Ctrl)
> 18 (Alt)
> 19 (Pause)
> 37 (Left)
> 38 (Up)
> 39 (Right)
> 40 (Down)

This way you can check whether such a key is pressed.

Untested but this should work. Please let me know if something doesn't work as it should.

EDIT: Added cross-browser support

Try using getElementById

<input type="text" id="a" onkeyup="Boxy.Check();">

Boxy.Check = function() {
    input = document.getElementById(
        document.getElementById('a').currentSelector.id
    ).value;
    console.log("\"" + input + "\"");
};

using PeeHaa's advice with unkeyup