Limit Form Field to Alpha Characters Only

It is certainly possible to create a keystroke script that behaves as you want, and it can be made backwards compatible to 3.02. Can you post what you have so far?

George

Hi George,

Thanks for the quick reply. My code is below. I admit to knowing just enough to be dangerous when it comes to JavaScript, so if the code seems not well written, please let me know.

if (event.willCommit == false) {
event.rc = /^[a-zA-Z]+$/.test(event.change);
}

Craig

Craig,

Reasonable start, but I would expand on that a bit. Begin by creating the following document-level JavaScript:

function chars_only_ks() {

// Get everything that the user has entered so far
var value = AFMergeChange(event);

// Do nothing if there are no characters
if(!value) return;

//If user attempts to enter an invalid sequence of characters, reject it
if(!AFExactMatch(/[A-Za-z]*/, value)) event.rc = false;
}

Note that the AFMergeChange and AFExactMatch functions are built-in convenience functions supplied by Acrobat and used by it for the various built-in Format/Keystroke options available.

Now that you've set up the above function, you can use the following as the custom Keystroke script for a field:

if (!event.willCommit) chars_only_ks();

And that should do it. If you're interested in studying the details of the two convenience functions so you understand exactly how they work, post again.

George

Thanks again George. This is great.

As I said earlier, I know just enough to be dangerous so I can't honestly say I understand all of what your script is doing. When I have a moment I intend to study it more carefully.

Craig

Note that the last line of the function can also be:

event.rc = AFExactMatch(/[A-Za-z]*/, value));


but sometimes it's good to be explicit when trying to convey the idea.

George