Web Front-endJS TutorialJavaScript enhancement tutorial - DOM programming (two methods of controlling div movement)JavaScript enhancement tutorial - DOM programming (two methods of controlling div movement)
The first button control
First create two html buttons and a div and give the div a style
input type="button" value="左" id="1">
<input type="button" value="右" id="2">
<div id="3">
div {
width: 100px;
height: 100px;
background-color: bisque;
position: absolute;
left: 100px;
top: 100px;
}Then get the div and two buttons in the script
var left = document.getElementById("2");
var right = document.getElementById("1");
var div = document.getElementById("3");Then add the onclick function
left.onclick = function () {
}
right.onclick = function () {
}Set a variable to control the left change of the div var x = 100;Triggered when the button is clicked
left.onclick = function () {
x=x+10;
div.style.left = x+"px";
}
right.onclick = function () {
x=x-10;
div.style.left = x+"px";
}Source code: <!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
div { width: 100px; height: 100px; background-color: bisque;
position: absolute; left: 100px; top: 100px; }
</style>
</head>
<body>
<input type="button" value="左" id="1"> <input type="button" value="右" id="2"> <div id="3"> </div>
<script>
var left = document.getElementById("2"); var right = document.getElementById("1");
var div = document.getElementById("3");
var x = 100;
left.onclick = function () { x=x+10; div.style.left = x+"px";
} right.onclick = function () { x=x-10; div.style.left = x+"px"; }
</script>
</body>
</html> Second type, key value control
Similarly create a div in html and give it style
<div id="3">
</div>
<style>
div {
width: 100px;
height: 100px;
background-color: bisque;
position: absolute;
left: 100px;
top: 100px;
}
</style>Get the div in the script
var div=document.getElementById("3");Then declare two variables to control changing the left and top of the div
var px=100; var py =100;
Then get the key value
document.onkeydown (in the document document object, pressing any key will trigger this function)## The event.keyCode output in #alert will correspond to the event value corresponding to the current key when the key is pressed (that is, each key corresponds to a key value)
document.onkeydown = function(){
alert(event.keyCode);
}
switch (event.keyCode){
case 37:
px = px-10;
div.style.left = px+"px";
break;
case 38:
py = py-10;
div.style.top = py+"px";
break;
case 39:
px = px+10;
div.style.left = px+"px";
break;
case 40:
py = py+10;
div.style.top = py+"px";
break;
} Source code:
Title
<script>
var div=document.getElementById("3");
var px=100;
var py =100;
document.onkeydown = function(){
// alert(event.keyCode);
switch (event.keyCode){ case 37: px = px-10;
div.style.left = px+"px"; break; case 38:
py = py-10; div.style.top = py+"px"; break;
case 39: px = px+10; div.style.left = px+"px";
break; case 40: py = py+10; div.style.top = py+"px"; break; }
}
</script>
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