function setupRollover(thisImage) {
thisImage.outImage = new Image();
thisImage.outImage.src = thisImage.src;
thisImage.onmouseout = rollOut; thisImage.overImage = new Image();
thisImage.overImage.src = "images/" + thisImage.id + "_on.gif";
thisImage.onmouseover = rollOver;
}
在一本书上看到这样的代码,我想问问,这个thisImage.outImage,outImage哪来的,这段代码之前没有声明它啊,这个怎么理解,哪位能帮我解释一下?
outImage 也是一个thisImage对象的属性(也是个对象)都是自定义的,你需要看源代码查
function setupRollover(thisImage) {
thisImage.outImage = new Image();
thisImage.outImage.src = thisImage.src;
thisImage.onmouseout = rollOut; thisImage.overImage = new Image();
thisImage.overImage.src = "images/" + thisImage.id + "_on.gif";
thisImage.onmouseover = rollOver;
}
</script>
<img src="" overImage="" outImage="" onmouseover="alert(this.overImage);" onmouseout="alert(this.outImage);">
function setupRollover(thisImage) {
thisImage.outImage = new Image();
thisImage.outImage.src = thisImage.src;
thisImage.onmouseout = rollOut; thisImage.overImage = new Image();
thisImage.overImage.src = "images/" + thisImage.id + "_on.gif";
thisImage.onmouseover = rollOver;
}
</script>
<img src="" overImage="进入图片" outImage="离开图片" onmouseover="alert(this.overImage);" onmouseout="alert(this.outImage);">
var o={}; // 声明应该对象
o.img=new Image(); // 动态添加应该属性并赋值
o.name="img"; // 动态添加应该属性并赋值