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Question

Are there any ways available in jquery to detect whether Enter key has pressed?

I know that we can use keycodes/charset to identify the Enter key press, but I do not need to hard code an integer value in my js script as it will become a magical number. I need to know whether there are any other possible ways to detect Enter key press, which is something like e.shiftKey for detecting shift key press using event object.

Thanks.

Answer 1

So, you want to detect the Enter key being pressed without hardcoding a 13 for the keycode.

Now, I could suggest using 6.5*2 as the keycode, then, but that'd be silly.

The real answer is that there is no built-in constant for the Enter key, like the Shift key has.

The reason Shift has it, is because that key is often pressed in combination with other keys. You can't detect a Shift keyDown event when pressing Shift + A , for example, because the event for the modifier has passed already when you're handling the keyDown event for the A .

Frankly, your only real option would be to hardcode a application-wide constant that says something along the lines of:

window.keyCodes = {
    Enter: 13,
    SomeKey: 99
}

Then you can check against it like this:

if(e.keyCode === keyCodes.Enter)

Or, it may be possible to write a function that compares the character of the entered key with a string that contains only a return, but then you'd just be hardcoding a return, any way.

Answer 2

The keycode for the enter key is : 13

if(e.keyCode == 13)
  //do something...

Answer 3

This is the immediate way that people detect this particular event, but there are other ways to identify the number 13.

var DOM_VK_RETURN = 13;

$(document).on('keydown', function(e) {
  var code = e.keyCode || e.which;
  if(code == DOM_VK_RETURN) {
    console.log("Enter key pressed");
  }
});

However, if you do not want to use an integer to detect the key, we could use hexadecimal.

http://jsfiddle.net/hk2eL/3/