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I want to eventing more keys in my Javascript code:

<script>
function OPEN(e) {
        if (e.type !== "blur") {
        if (e.keyCode === 70) {
            alert("Pressed F");
        }
    }
}
document.onkeydown = OPEN;
</script>
Teun Strik
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    I'm not entirely sure what your asking? What is the problem you are trying to solve? – Taplar Apr 25 '15 at 20:04
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    then add them, use [else if](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/if...else) or use a [switch](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/switch). Also I believe you are meaning "detect more keys" – Patrick Evans Apr 25 '15 at 20:06

3 Answers3

1

What I am getting from your question is that you want to detect more keys presses. The best way to detect key presses is a switch statement

function OPEN(e) {
  if (e.type !== "blur") {
    switch (e.keyCode) {
      case 70:
        alert("Pressed F");
        break;
        
      case 65:
        alert("Pressed A");
        break;
        
      default:
        alert("I don't know what to do with that key!");//This line is removable
        break;
    }
  }
}
document.onkeydown = OPEN;

How it works

The way a switch works is:

switch (VALUE) {
    case THIS_VALUE:
      CODE
      break;

     default:
      CODE
      break;
}

That was probably the worst explanation you've seen so you can read about here

Without keyCode

keyCodes are kind of irritating to figure out, you can use:

function OPEN(e) {
  if (e.type !== "blur") {
    switch (String.fromCharCode(e.keyCode)) {
      case "F":
        alert("Pressed F");
        break;

      case "A":
        alert("Pressed A");
        break;

      case "B":
        alert("Pressed B");

      default:
        alert("I don't know what to do with that key!");//This line is removable
        break;
    }
  }
}
document.onkeydown = OPEN;

Detect Key Combinations

When detecting key combinations, you can use && to make sure both key's are pressed. Without some more complicated. You can use:

e.metaKey Window key on Windows, Command Key on Mac

e.ctrlKey Control key

e.shiftKey Shift key

e.altKey Alt key

Use them as:

if (e.ctrlKey && e.keyCode === 65) {
    alert("Control and A key pressed");
}

To detect all keys are currently pressed (multiple) I found this fiddle (not mine), and a question here

Community
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Downgoat
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1

may be that make what you want

   <script>
    function OPEN(event) {
        var x = event.which || event.keyCode;
        alert( "The Unicode value is: " + String.fromCharCode(x));
    // The Unicode value is: a
    //The Unicode value is: b
    }
    </script>

then add this attr to your body

<body onkeydown="OPEN(event)">
Egy Success
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0

If you're not opposed to using a library for this, I find Mousetrap.js to be awesome and very easy to use.

Here are a few examples from the link above:

<script>
    // single keys
    Mousetrap.bind('4', function() { console.log('4'); });
    Mousetrap.bind("?", function() { console.log('show shortcuts!'); });
    Mousetrap.bind('esc', function() { console.log('escape'); }, 'keyup');

    // combinations
    Mousetrap.bind('command+shift+k', function() { console.log('command shift k'); });

    // map multiple combinations to the same callback
    Mousetrap.bind(['command+k', 'ctrl+k'], function() {
        console.log('command k or control k');

        // return false to prevent default browser behavior
        // and stop event from bubbling
        return false;
    });

    // gmail style sequences
    Mousetrap.bind('g i', function() { console.log('go to inbox'); });
    Mousetrap.bind('* a', function() { console.log('select all'); });

    // konami code!
    Mousetrap.bind('up up down down left right left right b a enter', function() {
        console.log('konami code');
    });
</script>
jbiz
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