IF statement?

[shamrox]

I have several text fields on page that I would like to make calculations based on if there is a number input in one of the fields.
So, if the price field is populated, the sale price field would populate using a function to do the calculation.
Now, how do I write the code for this to occur? I know how to get the function to fire based on clicking a submit button, but not sure how to do it simply based on a number keyed into the one field.
Is this possible and if so, how? Thanks a ton.

[NakedIntruder]

You'd need to;

1) get a reference to the price field
2) remove whitespace
3) check it's length is more than 0
4) check it is a number
5) if all's fine, do your calculation.


Hope that's on the right track, fairly rushed reply and am trying to imagine your form.

Hope it helps.

[shamrox]

What would force that function to fire though? Like I have functions that fire with the onClick. But what would I use to fire whenever?

[NakedIntruder]

ah sorry, you could use onblur (defocus) on the price field, but that may not be reliable enough, possibly onkeyup on the price field?

[shamrox]

Ah ok, gotcha now. Thanks for the assist, I'll give all that a go.