取得元素的左和上方偏移的方法_javascript技巧

 function getElementLeft(element) 
{ 
var actualLeft = element.offsetLeft; 
var current = element.offsetParent; 

while (current!==null) 
{ 
actualLeft += current.offsetLeft; 
current = current.offsetParent; 
} 
return actualLeft; 
}

取得元素的左偏移量；

function getElementTop(element) 
{ 
var actualTop = element.offsetTop; 
var current = element.offsetParent; 

while (current!==null) 
{ 
<span style="white-space:pre"> </span>actualTop += current.offsetTop; 
current = current.offsetParent; 
} 
return actualTop; 
}

取得元素的上偏移；

利用offsetParent屬性在Dom層次中逐級向上回溯，將每個層次偏移量合計。