在 keyup 事件中检测 Ctrl + A

Question

I want to detect the Control + A event in input. I can find the Control + A event, but the function is continuing even after return false .

jsFiddle - http://jsfiddle.net/f6rcgpmh/4/

 $('.searchTerm').keyup(function(e) { $("#status").text(""); if (e.ctrlKey) { if (e.keyCode == 65 || e.keyCode == 97) { // 'A' or 'a' console.log("Control pressed"); e.preventDefault(); return false; } } $("#status").text("This should not work if Ctrl + A is pressed"); });

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <form id="search" class="search"> <input class="searchTerm" placeholder="Filter Books..."> <input class="searchButton" type="submit"> </form> <div id="status"></div>

I want this to work in keyup not in keydown . Because I am using autosearch and I don't want to call function before keyrelease. And also Ctrl + A won't highlight text in keydown when it returned false.

Answer 1

Actually the function stops. What you are experiencing is that two keyup events trigger: the one from ctrl and the one from A .

The first one returns as expected because it does fill the requirements: ctrlKey == true and keyCode == 65 || keyCode == 97 keyCode == 65 || keyCode == 97 .

But the second one, there will be only one key pressed so both statements can't be true together:

• If you last released the ctrl , then ctrlKey is true but keyCode == 65 || keyCode == 97 keyCode == 65 || keyCode == 97 is not.

• If you last released the A , then ctrlKey is now false.

Then the line which sets #status to an error message is run.

Answer 2

Actually it's not. You must change your event from 'keyup' to 'keydown' . Then try it again. You can check this fiddle. http://jsfiddle.net/ebilgin/f6rcgpmh/5/

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If you need control on autocomplete, you have to put your controls before sending the data.

The Ctrl keyup event trigger causes your problem. I added another condition to your code,

if (e.keyCode == 17) // Ctrl key, fires at Ctrl's keyup.
    return false;

You can check my new fiddle, http://jsfiddle.net/ebilgin/f6rcgpmh/10/ .