Knockout - keyCode property not being passed through wrapped function

Question

I've set up my Knockout bindings to have a keypress event because I wish to detect Enter on an input field.

If I have the following:

data-bind="event: { keypress: KeyPress }"

and my view-model has

this.KeyPress = function(data, event) {
    console.log(event.keyCode);
}

then the keyCode shows up as expected.

However, I wish to pass an additional parameter to the function KeyPress, so following the example from here, I now have

data-bind="event: { keypress: function (data, event) { KeyPress('myParam', data, event); return true; } }" />

and my corresponding function now becomes

this.KeyPress = function(p, data, event) {
    console.log(event.keyCode);
}

Now, the keyCode property always returns 0. I can see inside the event object that the charCode property is being set for each key-press, but not the keyCode property (and the charCode property isn't much use because all non-printable characters are 0).

I can also see that the event object has an originalEvent property, but the keyCode in here is the same, i.e. 0.

So can anyone tell me how to get the keyCode property propagating through the function literal?

Here is a JsFiddle demonstrating it.

Answer 1

I'm guessing that you get this result 0 only in firefox

so change your code into this:

this.KeyPress = function(p, data, event) {
    console.log(window.event ? event.keyCode : event.which);
}