用javascript实现点击链接弹出图片另存为而不是直接打开
<iframe height="0" width="0" src="/images/logo.gif" name="saveImage" id="saveImage"></iframe>
<a href="javascript:void(0);" onclick="saveImage.document.execCommand('saveAs');">Click Me</a> <iframe height="0" width="0" src="/images/logo.gif" name="saveImage" id="saveImage"></iframe>
<a href="javascript:void(0);" onclick="saveImage.document.execCommand('saveAs');">Click Me</a>