<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>无标题文档</title>
<script language="javascript">
function alertWin(str){
var msgw, msgh, bordercolor;
msgw = 300;//提示窗口的宽度
msgh = 100;//提示窗口的高度
titleheight = 25 //提示窗口标题高度
bordercolor = "#A480B2";//提示窗口的边框颜色
titlecolor = "#A480B2";//提示窗口的标题颜色
//根据自己需求注意宽度和高度的调整
var iWidth = document.documentElement.clientWidth;
var iHeight = document.documentElement.clientHeight;
//遮罩层
var bgObj = document.createElement("div");
bgObj.setAttribute("id", "bgObj");//设置ID
bgObj.style.cssText = "position:absolute;left:0px;top:0px;width:"+iWidth+"px;height:"+Math.max(document.body.clientHeight, iHeight)+"px;filter:Alpha(Opacity=30);opacity:0.3;background-color:#000000;z-index:101;";
document.body.appendChild(bgObj);
//弹出窗口
var msgObj=document.createElement("div");
msgObj.setAttribute("id", "msgDiv");//可以用bgObj.id="msgDiv"的方法，是为div指定属性值
msgObj.setAttribute("align", "center");//为div的align赋值
msgObj.style.background = "white";//背景颜色为白色
msgObj.style.border = "1px solid " + bordercolor;//边框属性，颜色在上面已经赋值
msgObj.style.position = "absolute";//绝对定位
msgObj.style.left = (iWidth-msgw)/2 ;//从左侧开始位置
msgObj.style.top = (iHeight-msgh)/2;//从上部开始位置
msgObj.style.font = "12px/1.6em Verdana, Geneva, Arial, Helvetica, sans-serif";//字体属性
msgObj.style.width = msgw + "px";//提示框的宽(上面定义过)
msgObj.style.height = msgh + "px";//提示框的高(上面定义过)
msgObj.style.textAlign = "center";//文本位置属性，居中。
msgObj.style.lineHeight = "25px";//行间距
msgObj.style.zIndex = "102";//层的z轴位置
document.body.appendChild(msgObj);
//弹出窗口标题
var title = document.createElement("div");//创建一个标题对象
title.setAttribute("id", "msgTitle");//为标题对象填加id
title.style.margin = "0";//浮动
title.style.padding = "3px";//浮动
title.style.background = titlecolor;//背景颜色
title.style.filter = "progid:DXImageTransform.Microsoft.Alpha(startX=20, startY=20, finishX=100, finishY=100,style=1,opacity=75,finishOpacity=100);";
title.style.opacity = "0.75";//透明
//title.style.border="1px solid " + bordercolor;//边框
title.style.height = "25px";//高度
title.style.font = "12px Verdana, Geneva, Arial, Helvetica, sans-serif";//字体属性
//title.style.color = "red";//文字颜色
title.style.cursor = "move";//鼠标样式
title.innerHTML="<table border=‘0‘ width=‘100%‘><tr><td align=‘left‘>2222</td><td align=\"right\"><a href=‘#‘ onclick=‘closeDiv()‘>x</a></td></tr></table>";
//设置窗口可移动
var moveX = 0;
var moveY = 0;
var moveTop = 0;
var moveLeft = 0;
var moveable = false;
var docMouseMoveEvent = document.onmousemove;
var docMouseUpEvent = document.onmouseup;
title.onmousedown = function() {
var evt = getEvent();
moveable = true;
moveX = evt.clientX;
moveY = evt.clientY;
moveTop = parseInt(msgObj.style.top);
moveLeft = parseInt(msgObj.style.left);
document.onmousemove = function() {
if (moveable){
var evt = getEvent();
var x = moveLeft + evt.clientX - moveX;
var y = moveTop + evt.clientY - moveY;
if ( x > 0 &&( x + msgw < iWidth) && y > 0 && (y + msgh < iHeight) ){
msgObj.style.left = x + "px";
msgObj.style.top = y + "px";
}
}
};
document.onmouseup = function (){
if (moveable) {
document.onmousemove = docMouseMoveEvent;
document.onmouseup = docMouseUpEvent;
moveable = false;
moveX = 0;
moveY = 0;
moveTop = 0;
moveLeft = 0;
}
};
}
//获得事件Event对象，用于兼容IE和FireFox
function getEvent() {
return window.event || arguments.callee.caller.arguments[0];
}
msgObj.appendChild(title);//在提示框中增加标题
var txt = document.createElement("p");
txt.style.margin = "1em 0";//文本浮动
txt.setAttribute("id", "msgTxt");//为p属性增加id属性
txt.innerHTML = str;//把传进来的值赋给p属性
msgObj.appendChild(txt);//把p属性增加到提示框里
}
//添加关闭功能
function closeDiv() {
var msgTitelObject = document.getElementById("msgDiv");
document.body.removeChild(msgTitelObject);
var bgObj = document.getElementById("bgObj");
document.body.removeChild(bgObj);
}
</script>
</head>
<body>
<input type="button" value="xx" onclick="alertWin(‘消息主题‘);" />
</body>
</html>
原文地址：https://www.cnblogs.com/yangpeng-jingjing/p/8331022.html