最喜欢的是chrome,不要问我为什么

//简单弹窗
function openAlert(settings){
	var msg=settings.msg===undefined?"ok":settings.msg,
      type=settings.type===undefined?"alert":settings.type,
		  title=settings.title===undefined?"提示信息":settings.title,
    	confirmBtn=settings.confirmBtn===undefined?"确定":settings.confirmBtn,
    	closeBtn=settings.closeBtn===undefined?"取消":settings.closeBtn,
		  openCallback=settings.openCallBack===undefined?function(){}:settings.openCallBack,
    	closeCallBack=settings.closeCallBack===undefined?function(){}:settings.closeCallBack,
        confirmCallBack=settings.confirmCallBack===undefined?function () {}:settings.confirmCallBack;
    var parentobj=$(window.top.document.body);
	if(type=="alert")
	{
        parentobj.find(".btn_confirm").hide()
        openCallback(msg)
	}else if(type=="confirm"){
        parentobj.find(".btn_confirm").show()
        openCallback(msg)
	}
	
    parentobj.find(".btn_confirm").text(confirmBtn);
    parentobj.find(".btn_close").text(closeBtn);
    parentobj.find(".modal-title").html(title);
    parentobj.find(".modal-body").html(msg);
    parentobj.find(".modal").removeClass("fade").show();
    
    //关闭弹窗
    parentobj.find(".btn_close,.close").unbind('click').bind('click',function(){
        parentobj.find(".modal-body > p").text("");
        parentobj.find(".modal").addClass("fade").hide();
        closeCallBack(msg,parentobj.find(".modal").addClass("fade").hide(),this)
    })
	//点击确定按钮
    parentobj.find(".btn_confirm").unbind('click').bind('click',function(){
        confirmCallBack(msg,parentobj.find(".modal").addClass("fade").hide(),this)
    })
     //判断是否为firefox
    
     if(navigator.userAgent.indexOf('Firefox') >= 0){
        setTimeout(function(){
            var _top=($(window).height()-$(".modal-content").height())/2;
            if($(".modal-content").length!=0){
                $(".modal-content").css("transform","translateY("+_top+"px)");
            }else{
                $(window.parent.document.querySelector(".modal-content")).css("transform","translateY("+_top+"px)");
            }
        })
    }
}

//页面代码
    <div class="modal fade" id="addModal" tabindex="-1" role="dialog" aria-hidden="true" style="background: rgba(0, 0, 0, 0.25);z-index:100000000!important;">
            <div class="modal-dialog" role="document" style="width:320px;">
                <div class="modal-content">
                    <div class="modal-header">
                        <button type="button" class="close"><span aria-hidden="true">&times;</span></button>
                        <h4 class="modal-title">消息提示</h4>
                    </div>
                    <div class="modal-body">
                        <p> </p>
                    </div>
                    <div class="modal-footer">
                        <button type="button" class="btn btn-primary btn_confirm">提交</button>
                        <button type="button" class="btn btn-default btn_close">关闭</button>
                    </div>
                </div>
            </div>
        </div>
.modal-dialog {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    margin: auto;
    display: table;
}
.modal-content {
    background-clip: padding-box;
    background-color: #FFF;
    border: 1px solid #0000;
    border-radius: 4px;
    box-shadow: 0 1px 3px rgba(0,0,0,.3);
    outline: 0 none;
}
.modal-header {
    padding: 15px;
    border-bottom: 1px solid #e5e5e5;
}
.modal-body {
    padding: 20px 30px 30px;
}
.modal-footer {
    padding: 15px;
    text-align: right;
    border-top: 1px solid #e5e5e5;
}
event 兼容 firfox

var event = window.event || arguments.callee.caller.arguments[0];
var files=event.target.files;
<!--[if lt IE 9]>
<meta http-equiv="refresh" content="0;ie.html" />
<![endif]-->
if (!document.addEventListener) {
    // IE6~IE8
    document.write('__MAIN_HOST__/Public/assets/manage/js/ieBetter.js'); 
}
针对ie

if (!!window.ActiveXObject || "ActiveXObject" in window){

}
针对firfox
if(navigator.userAgent.indexOf('Firefox') >= 0){

}
head

未完待续…