window.alert = function(str) { var shield = document.createElement("DIV"); shield.id = "shield"; shield.style.position = "absolute"; shield.style.left = "0px"; shield.style.top = "0px"; shield.style.width = "100%"; shield.style.height = document.body.scrollHeight+"px"; //弹出对话框时的背景颜色 shield.style.background = "#fff"; shield.style.textAlign = "center"; shield.style.zIndex = "25"; //背景透明 IE有效 //shield.style.filter = "alpha(opacity=0)"; var alertFram = document.createElement("DIV"); alertFram.id="alertFram"; alertFram.style.position = "absolute"; alertFram.style.left = "50%"; alertFram.style.top = "50%"; alertFram.style.marginLeft = "-225px"; alertFram.style.marginTop = "-75px"; alertFram.style.width = "450px"; alertFram.style.height = "150px"; alertFram.style.background = "#ff0000"; alertFram.style.textAlign = "center"; alertFram.style.lineHeight = "150px"; alertFram.style.zIndex = "300"; strHtml = "<ul style=\"list-style:none;margin:0px;padding:0px;width:100%\">\n"; strHtml += " <li style=\"background:#DD828D;text-align:left;padding-left:20px;font-size:14px;font-weight:bold;height:25px;line-height:25px;border:1px solid #F9CADE;\">[自定义提示]</li>\n"; strHtml += " <li style=\"background:#fff;text-align:center;font-size:12px;height:120px;line-height:120px;border-left:1px solid #F9CADE;border-right:1px solid #F9CADE;\">"+str+"</li>\n"; strHtml += " <li style=\"background:#FDEEF4;text-align:center;font-weight:bold;height:25px;line-height:25px; border:1px solid #F9CADE;\"><input type=\"button\" value=\"确 定\" onclick=\"doOk()\" /></li>\n"; strHtml += "</ul>\n"; alertFram.innerHTML = strHtml; document.body.appendChild(alertFram); document.body.appendChild(shield); var ad = setInterval("doAlpha()",5); this.doOk = function(){ alertFram.style.display = "none"; shield.style.display = "none"; } alertFram.focus(); document.body.onselectstart = function(){return false;}; }