js多物體任意值運動
假如有兩個div,一個div要變寬,一個div要變高,你怎麼寫呢? 哎呀,寫2個方法啊,一個控制div1變寬,一個控制div2變高啊 那麼你的代碼,是不是下面這樣的呢! 樣本:Div變寬和變高 現象:div1在onmouseover時變寬,onmouseout時恢複原大小; div2在onmouseover時變高,onmouseout時恢複原大小 缺點:重複的代碼寫了好幾個方法 html部分 <div id="div1"></div><div id="div2"></div> <style> div { width:100px; height:150px; margin:20px; background:green;}</style> js部分 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253<script> window.onload = function(){ var oDiv1 = document.getElementById("div1"); var oDiv2 = document.getElementById("div2"); oDiv1.onmouseover = function(){ startMove1(this,300); } oDiv1.onmouseout = function(){ startMove1(this,100); } oDiv2.onmouseover = function(){ startMove2(this,300); } oDiv2.onmouseout = function(){ startMove2(this,150); } } function startMove1(obj,iTarget){ clearInterval(obj.timer); obj.timer = setInterval(function(){ var speed = (iTarget - obj.offsetWidth)/6; speed = speed > 0 ? Math.ceil(speed) : Math.floor(speed); if(obj.offsetWidth == iTarget){ clearInterval(obj.timer); } else { obj.style.width = obj.offsetWidth + speed + "px"; } },30);} function startMove2(obj,iTarget){ clearInterval(obj.timer); obj.timer = setInterval(function(){ var speed = (iTarget - obj.offsetHeight)/6; speed = speed > 0 ? Math.ceil(speed) : Math.floor(speed); if(obj.offsetHeight == iTarget){ clearInterval(obj.timer); } else { obj.style.height = obj.offsetHeight + speed + "px"; } },30);} </script> 額,上面的代碼,本來是一個運動架構的,卻寫了兩個類似的方法。 而且還使用了offset,這是有缺陷的啊 那麼,可不可以用一個方法就解決這個問題了呢。 可以的 回想 js你真的瞭解offsetWidth嗎,有沒有給我們帶來什麼啟發呢? http://www.cnblogs.com/huaci/p/3863797.html 對了,利用function getStyle(obj,name),我們就可以控制多個屬性值的改變啦 原理:var attr= parseInt(getStyle(obj,name)); 修改後的完整代碼,如下: js部分 <script> window.onload = function(){ var oDiv1 = document.getElementById("div1"); var oDiv2 = document.getElementById("div2"); oDiv1.onmouseover = function(){ startMove(this,"width",300); } oDiv1.onmouseout = function(){ startMove(this,"width",100); } oDiv2.onmouseover = function(){ startMove(this,"height",300); } oDiv2.onmouseout = function(){ startMove(this,"height",150); } } function startMove(obj,name,iTarget){ clearInterval(obj.timer); obj.timer = setInterval(function(){ var attr = parseInt(getStyle(obj,name)); var speed = (iTarget - attr)/6; speed = speed > 0 ? Math.ceil(speed) : Math.floor(speed); if(attr == iTarget){ clearInterval(obj.timer); } else { obj.style[name] = attr + speed + "px"; } },30);} function getStyle(obj,name){ if(obj.currentStyle){ return obj.currentStyle[name]; } else{ getComputed(obj,null)[name]; } }