如何用javascript实现图片变换

Question

做了一个按钮 想让鼠标移上去的时候变换按钮图片 怎么呢写？我写的无法响应鼠标事件
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<a href="blog.html"onMouseOver="sitowbutton2.png" onMouseOut="sitowbutton1.png"><img src="sitowbutton1.png" width="162" height="74" border="0"></a>

Answer 1

<a href="blog.html""><img src="sitowbutton1.png" width="162" height="74" onMouseOver="javascript:this.src='sitowbutton2.png'" onMouseOut="javascript:this.src='sitowbutton1.png'" border="0"></a>