function DownLoadReportIMG(imgPathURL) {
         
        //如果隐藏IFRAME不存在，则添加
        if (!document.getElementById("IframeReportImg"))
            $('<iframe style="display:none;" id="IframeReportImg" name="IframeReportImg" onload="DoSaveAsIMG();" width="0" height="0" src="about:blank"></iframe>').appendTo("body");
        if (document.all.IframeReportImg.src != imgPathURL) {
            //加载图片
            document.all.IframeReportImg.src = imgPathURL;
        }
        else {
            //图片直接另存为
            DoSaveAsIMG();  
        }
    }
    function DoSaveAsIMG() {
        if (document.all.IframeReportImg.src != "about:blank")
            document.frames("IframeReportImg").document.execCommand("SaveAs");        
    }