javascript重写alert方法
最近因为在flash项目中遇到as调用js函数马上弹出alert,在火狐浏览器下会卡死浏览器。介于这样我们重写alert,让alert弹出一个自定义的div弹层,来实现提示效果!
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>重写alert</title> <link href="css/style.css" rel="stylesheet"/> <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.5.2/jquery.min.js"></script> <script type="text/javascript"> var showAlert = function(msg){ jAlert(msg, "提示!"); } window.alert=showAlert; $.alerts={ verticalOffset:-75,horizontalOffset:0,repositionOnResize:true,overlayOpacity:.01,overlayColor:'#FFF',draggable:true,okButton:' OK ',cancelButton:' Cancel ',dialogClass:null,alert:function(message,title,callback){ if(title==null)title='Alert'; $.alerts._show(title,message,null,'alert',function(result){ if(callback)callback(result) }) } ,_show:function(title,msg,value,type,callback){ $.alerts._hide(); $.alerts._overlay('show'); $("BODY").append('<div id="popup_container">'+'<h1 id="popup_title"></h1>'+'<div id="popup_content">'+'<div id="popup_message"></div>'+'</div>'+'</div>'); if($.alerts.dialogClass)$("#popup_container").addClass($.alerts.dialogClass); var pos=($.browser.msie&&parseInt($.browser.version)<=6)?'absolute':'fixed'; $("#popup_container").css({ position:pos,zIndex:99999,padding:0,margin:0 }); $("#popup_title").text(title); $("#popup_content").addClass(type); $("#popup_message").text(msg); $("#popup_message").html($("#popup_message").text().replace(/\n/g,'<br />')); $("#popup_container").css({ minWidth:$("#popup_container").outerWidth(),maxWidth:$("#popup_container").outerWidth() }); $.alerts._reposition(); $.alerts._maintainPosition(true); switch(type){ case'alert':$("#popup_message").after('<div id="popup_panel"><input type="button" value="'+$.alerts.okButton+'" id="popup_ok" /></div>'); $("#popup_ok").click(function(){ $.alerts._hide(); callback(true) }); $("#popup_ok").focus().keypress(function(e){ if(e.keyCode==13||e.keyCode==27)$("#popup_ok").trigger('click') }); break }; if($.alerts.draggable){ try{ $("#popup_container").draggable({ handle:$("#popup_title") }); $("#popup_title").css({ cursor:'move' }) } catch(e){} } } ,_hide:function(){ $("#popup_container").remove(); $.alerts._overlay('hide'); $.alerts._maintainPosition(false) } ,_overlay:function(status){ switch(status){ case'show':$.alerts._overlay('hide'); $("BODY").append('<div id="popup_overlay"></div>'); $("#popup_overlay").css({ position:'absolute',zIndex:99998,top:'0px',left:'0px',width:'100%',height:$(document).height(),background:$.alerts.overlayColor,opacity:$.alerts.overlayOpacity }); break; case'hide':$("#popup_overlay").remove(); break } } ,_reposition:function(){ var top=(($(window).height()/ 2) - ($("#popup_container").outerHeight() /2))+$.alerts.verticalOffset; var left=(($(window).width()/ 2) - ($("#popup_container").outerWidth() /2))+$.alerts.horizontalOffset; if(top<0)top=0; if(left<0)left=0; if($.browser.msie&&parseInt($.browser.version)<=6)top=top+$(window).scrollTop(); $("#popup_container").css({ top:top+'px',left:left+'px' }); $("#popup_overlay").height($(document).height()) } ,_maintainPosition:function(status){ if($.alerts.repositionOnResize){ switch(status){ case true:$(window).bind('resize',function(){ $.alerts._reposition() }); break; case false:$(window).unbind('resize'); break } } } }; jAlert=function(message,title,callback){ $.alerts.alert(message,title,callback) } $(function(){alert("hello word!")}) </script> <style> #popup_container{font-family:Arial,sans-serif;font-size:12px;min-width:300px;max-width:600px;background:#FFF;border:solid 5px #999;color:#000;-moz-border-radius:5px;-webkit-border-radius:5px;border-radius:5px;}#popup_title{font-size:14px;font-weight:bold;text-align:center;line-height:1.75em;color:#666;background:#CCC url(images/title.gif) top repeat-x;border:solid 1px #FFF;border-bottom:solid 1px #999;cursor:default;padding:0em;margin:0em;}#popup_content{background:16px 16px no-repeat url(images/info.gif);padding:1em 1.75em;margin:0em;}#popup_content.alert{background-image:url(images/info.gif);}#popup_message{padding-left:48px;}#popup_panel{text-align:center;margin:1em 0em 0em 1em;}#popup_prompt{margin:.5em 0em;} </style> </head> <body> </body> </html>