错在哪里了？没有拖动的效果出来！

源自：8-2 综合实战题

错在哪里了？没有拖动的效果出来！

<!DOCTYPE html>

<html>

<head>

#draggable{ width: 100px;height: 100px; position: absolute;top: 100px;left: 100px;border: 1px solid #ccc;background: #eee;padding: 10px;cursor: default;}

</style>

</head>

<body>

var oDrag = document.getElementById('draggable');

var isDraging = false;

var startX = 0;

var startY = 0;

oDrag.addEventListener('mousedown',function(e){

//鼠标事件1 - 在标题栏按下（要计算鼠标相对拖拽元素的左上角的坐标，并且标记元素为可拖动）

var e=e||window.event;

startX = e.pageX-g("oDrag").offSetLeft;

startY = e.pageY-g("oDrag").offSetTop;

isDragging=true;

})

document.onmouseup = function(e){

//鼠标事件3 - 鼠标松开的时候（标记元素为不可拖动）

isDragging=false;

}

document.onmousemove = function(e) {

//鼠标事件2 - 鼠标移动时（要检测，元素是否标记为移动）

var e = e||window.event;

var mouseX = e.pageX;

var mouseY = e.pageY;

var moveX = 0;

var moveY = 0;

if(isDragging === true){

moveX = mouseX - startX;

moveY = mouseY - startY;

var pageWidth = document.documentElement.clientWidth;

var pageHeight = document.documentElement.clientHeight;

var dialogWidth = oDrag.offsetWidth;

var dialogHeight = oDrag.offsetHeight;

var maxX = pageWidth-dialogWidth;

var maxY = pageHeight - dialogHeight;

moveX = Math.min(maxX,Math.max(0,moveX));

moveY = Math.min(maxY,Math.max(0,moveY));

oDrag.style.left = moveX+'px';

oDrag.style.top = moveY+'px';

};

</script>

</body>

</html>

提问者：stay123 2015-01-24 12:09

错在哪里了？没有拖动的效果出来！

个回答