知识点:
1,键盘window.event事件的接收,IE和firefox
2,判断碰撞的小函数
3,代码参考韩老师
4,index.html一个文件,2张图片
5,div属性,要设置成position:absolute
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script type="text/javascript">
function move(obj){
var wugui_height=67;
var wugui_width=94;
var tuzi_height=73;
var tuzi_width=76;
var wugui=document.getElementById('wugui');
var tuzi=document.getElementById('tuzi');
if(window.event|| arguments.callee.caller.arguments[0]){
key=obj.keyCode;
}
//得到乌龟当前的top和left
var wugui_top=wugui.style.top;
var wugui_left=wugui.style.left;
//处理px后缀
wugui_top=parseInt(wugui_top.substring(0,wugui_top.indexOf("p")));
wugui_left=parseInt(wugui_left.substring(0,wugui_left.indexOf("p")));
//判断用户点击了哪个键
if(obj.value=="向下走"||key==83){
wugui.style.top=(wugui_top+10)+"px";
wugui_top=wugui_top+10;
}else if(obj.value=="向右走"||key==68){
wugui.style.left=(wugui_left+10)+"px";
wugui_left=wugui_left+10;
}else if(obj.value=="向左走"||key==65){
wugui.style.left=(wugui_left-10)+"px";
wugui_left=wugui_left-10;
}else if(obj.value=="向上走"||key==87){
wugui.style.top=(wugui_top-10)+"px";
wugui_top=wugui_top-10;
}
//下面判断乌龟和兔子 碰到,应该可以做成一个函数
var tuzi_top=tuzi.style.top;
var tuzi_left=tuzi.style.left;
tuzi_top=parseInt(tuzi_top.substring(0,tuzi_top.indexOf("p")));
tuzi_left=parseInt(tuzi_left.substring(0,tuzi_left.indexOf("p")));
y=Math.abs(wugui_top-tuzi_top);
x=Math.abs(wugui_left-tuzi_left);
//方法
//判断条件
xx=0;
yy=0;
//纵向判断
if(wugui_top<tuzi_top){
if(y<wugui_height){
yy=1;
}
}else{
if(y<tuzi_height){
yy=1;
}
}
//横向判断
if(wugui_left<tuzi_left){
if(x<wugui_width){
xx=1;
}
}else{
if(x<tuzi_width){
xx=1;
}
}
if(xx==1&&yy==1){
window.alert("抓到了");
wugui.style.top=120+"px";
wugui.style.left=100+"px";
}
}
</script>
</head>
<body onkeydown="return move(event)">
<!--
作者:offline
时间:2016-10-25
描述://把乌龟放在这个div
-->
<div id="wugui" style="position:absolute ;left:100px;top:120px;" >
<img src="wugui.png" border="1" alt="乌龟" width="94" height="67"/>
</div>
<div id="tuzi" style="position:absolute ;left:300px;top:200px;" >
<img src="tuzi.png" border="1" alt="兔子" width="76" height="73"/>
</div>
<table border="1" cellspacing="0" cellpadding="10" width="300">
<tr><th> </th><th><input type="button" value="向上走" onclick="move(this)" /></th><th> </th></tr>
<tr><td><input type="button" value="向左走" onclick="move(this)" /></td>
<td><input type="button" value="向下走" onclick="move(this)" /></td>
<td><input type="button" value="向右走" onclick="move(this)" /></td></tr>
</table>
</body>
</html>