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Answer 1

A:

As this event is to move whatever from one position to one position, why don't you use onkeypress event, so in that way if the user key pressed the up key, the whatever will keep moving up, as the Pressed(e) will be called many times until the user releases the key.

<body onLoad="Load()" onkeypress="Pressed(event)">

Garis Suero 2010-09-11 15:13:33

same problem. the delay of 1 sec is still there, and when two keys are pressed, it only recognizez 1 of them.

alex 2010-09-11 15:26:02

Answer 2

+4 A:

If you want key repeat in a controllable fashion, you will have to implement it yourself, as keypress events are fired dependent on the OS's idea of how keys should repeat. That means there may be variable initial and following delays, and holding down two keys at once will cause only one of them to repeat.

You will have to keep a record of whether each key is currently pressed, and ignore keydown events when the key is already down. This is because many browsers will fire a keydown as well as a keypress event when an autorepeat occurs, and if you're reproducing key repeat yourself you'll need to suppress that.

For example:

// Keyboard input with customisable repeat (set to 0 for no key repeat)
//
function KeyboardController(keys, repeat) {
    // Lookup of key codes to timer ID, or null for no repeat
    //
    var timers= {};

    // When key is pressed and we don't already think it's pressed, call the
    // key action callback and set a timer to generate another one after a delay
    //
    document.onkeydown= function(event) {
        var key= (event || window.event).keyCode;
        if (!(key in keys))
            return true;
        if (!(key in timers)) {
            timers[key]= null;
            keys[key]();
            if (repeat!==0)
                timers[key]= setInterval(keys[key], repeat);
        }
        return false;
    };

    // Cancel timeout and mark key as released on keyup
    //
    document.onkeyup= function(event) {
        var key= (event || window.event).keyCode;
        if (key in timers) {
            if (timers[key]!==null)
                clearInterval(timers[key]);
            delete timers[key];
        }
    };

    // When window is unfocused we may not get key events. To prevent this
    // causing a key to 'get stuck down', cancel all held keys
    //
    window.onblur= function() {
        for (key in timers)
            if (timers[key]!==null)
                clearInterval(timers[key]);
        timers= {};
    };
};

then:

// Arrow key movement. Repeat key five times a second
//
KeyboardController({
    37: function() { Move(-1, 0); },
    38: function() { Move(0, -1); },
    39: function() { Move(1, 0); },
    40: function() { Move(0, 1); }
}, 200);

Although, most action-based games have a fixed-time main frame loop, which you can tie the key up/down handling into.

bobince 2010-09-11 16:04:33

yes, Ive tryed to fix it like this: <body onKeyDown="Down(event)" onKeyUp="Up(event)" /> but it doesn't fire at all

alex 2010-09-11 16:17:42

Answer 3

+1 A:

You could start the movement onkeydown and only end it onkeyup?

ikanobori 2010-09-11 16:08:32

Answer 4

+1 A:

I've solved it like this:

var pressedl = 0;
var pressedu = 0;
var pressedr = 0;
var pressedd = 0;

function Down(e) { 
        cxc = e.keyCode;
        if(cxc == 37)
            pressedl = 1;
        if(cxc == 38)
            pressedu = 1;
        if(cxc == 39)
            pressedr = 1;
        if(cxc == 40)
            pressedd = 1;
        //alert(cxc);
    }
    function Up(e) {
        cxc = e.keyCode;
        if(cxc == 37)
            pressedl = 0;
        if(cxc == 38)
            pressedu = 0;
        if(cxc == 39)
            pressedr = 0;
        if(cxc == 40)
            pressedd = 0;
        //alert(cxc);
    }

<body onLoad="Load()" onKeyDown="Down(event)" onKeyUp="Up(event)">

alex 2010-09-11 16:23:05

Thanks to bobince for pointing me in the right direction!

alex 2010-09-11 16:28:49

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remove key press delay in javascript

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