如果手上有现成元件可以这样搞
500) {this.resized=true; this.width=500; this.alt='这是一张缩略图,点击可放大。\n按住CTRL,滚动鼠标滚轮可自由缩放';this.style.cursor='hand'}" onclick="if(!this.resized) {return true;} else {window.open('http://u.dianyuan.com/bbs/u/46/1160186579.gif');}" onmousewheel="return imgzoom(this);"> www.infineon.com www.irf.com等网上都有.