通过Javascript创建一个选择文件的对话框代码

CSS 样式:

DIV.neat-dialog-cont { 
Z-INDEX: 98; BACKGROUND: none transparent scroll repeat 0% 0%; LEFT: 0px; WIDTH: 100%; POSITION: absolute; TOP: 0px; HEIGHT: 100% 
} 
DIV.neat-dialog-bg { 
Z-INDEX: -1; FILTER: alpha(opacity=70); LEFT: 0px; WIDTH: 100%; POSITION: absolute; TOP: 0px; HEIGHT: 100%; BACKGROUND-COLOR: #eee; opacity: 0.7; 
} 
DIV.neat-dialog { 
BORDER-RIGHT: #555 1px solid; BORDER-TOP: #555 1px solid; Z-INDEX: 99; MARGIN-LEFT: 35%; BORDER-LEFT: #555 1px solid; WIDTH: 300px; MARGIN-RIGHT: auto; 
BORDER-BOTTOM: #555 1px solid; POSITION: relative; TOP: 25%; BACKGROUND-COLOR: #fff 
} 
DIV.neat-dialog-title { 
PADDING-RIGHT: 0.3em; PADDING-LEFT: 0.3em; FONT-SIZE: 1em; PADDING-BOTTOM: 0.1em; MARGIN: 0px; LINE-HEIGHT: 1.2em; PADDING-TOP: 0.1em; BORDER-BOTTOM: #444 
1px solid; POSITION: relative;background: #36C;color:White; 
} 
DIV.neat-dialog P { 
PADDING-RIGHT: 0.2em; PADDING-LEFT: 0.2em; PADDING-BOTTOM: 0.2em; PADDING-TOP: 0.2em; TEXT-ALIGN: center 
}

Javascript 代码 ：

//打开弹窗 
function f_OpenDialog() { 
var sHTML = '<p><input id="txtFile" type="file" /></p>' + 
'<p><input id="btnYes" type="button" onclick="f_ReadExcel();" value="确定">' + 
'<button id="btnNo" onclick="window.neatDialog.close();">取消</button></p>'; 
new NeatDialog(sHTML, "请选择Excel文档!"); 
} 
//关闭并移除弹窗 
NeatDialog.prototype.close = function () { 
if (this.elt) { 
this.elt.style.display = "none"; 
this.elt.parentNode.removeChild(this.elt); 
} 
window.neatDialog = null; 
} 
//创建弹窗 
function NeatDialog(sHTML, sTitle) { 
window.neatDialog = null; 
this.elt = null; 
if (document.createElement && document.getElementById) { 
var dg = document.createElement("div"); 
dg.className = "neat-dialog"; 
if (sTitle) 
sHTML = '<div class="neat-dialog-title">' + sTitle + '</div>\n' + sHTML; 
dg.innerHTML = sHTML; 
var dbg = document.createElement("div"); 
dbg.id = "nd-bdg"; 
dbg.className = "neat-dialog-bg"; 
var dgc = document.createElement("div"); 
dgc.className = "neat-dialog-cont"; 
dgc.appendChild(dbg); 
dgc.appendChild(dg); 
if (document.body.offsetLeft > 0) { 
dgc.style.marginLeft = document.body.offsetLeft + "px"; 
} 
document.body.appendChild(dgc); 
this.elt = dgc; 
window.neatDialog = this; 
} 
}

效果：