I want to be able to move an image around the screen with JavaScript. The code I have below will put the image on the screen but will not let me move it around.
Question: Want to be able to move the image around the screen with the arrow keys?
I am certain there has to be a game loop that somehow is running all the time when the page is active. How this is done I am not certain either but I think that it might be int he load function.
JavaScript Code:
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Test Move Object</title>
<script type="text/javascript">
<script type="text/javascript">
function leftArrowPressed() {
var element = document.getElementById("image1");
element.style.left = parseInt(element.style.left) - 5 + 'px';
}
function rightArrowPressed() {
var element = document.getElementById("image1");
element.style.left = parseInt(element.style.left) + 5 + 'px';
}
function upArrowPressed() {
var element = document.getElementById("image1");
element.style.top = parseInt(element.style.top) - 5 + 'px';
}
function downArrowPressed() {
var element = document.getElementById("image1");
element.style.top = parseInt(element.style.top) + 5 + 'px';
}
function moveSelection() {
evt = evt || window.event;
switch (evt.keyCode) {
case 37:
leftArrowPressed();
break;
case 39:
rightArrowPressed();
break;
case 38:
upArrowPressed();
break;
case 40:
downArrowPressed();
break;
}
};
function gameLoop()
{
// change position based on speed
moveSelection();
setTimeout("gameLoop()",10);
}
</script>
</head>
<body onload="gameLoop()" onkeydown="" onkeyup="" bgcolor='yellow'>
Test
<img id="image1" src="C:Usersitpr13266Desktopmp.jpg" style="position:absolute;"
height="15" width="15">
</body>
end html
</html>
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