JavaScript rewrites the instance code of alert method

    $.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');
            $("BODY").append('<div >'+'<h1 ></h1>'+'<div >'+'<div ></div>'+'</div>'+'</div>');
            if($.)$("#popup_container").addClass($.);
            var pos=($.&&parseInt($.)<=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 ><input type="button" value="'+$.+'" /></div>');
                $("#popup_ok").click(function(){
                    $.alerts._hide();
                    callback(true)
                });
                $("#popup_ok").focus().keypress(function(e){
                    if(==13||==27)$("#popup_ok").trigger('click')
                });
                break
            };
            if($.){
                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 ></div>');
                $("#popup_overlay").css({
                    position:'absolute',zIndex:99998,top:'0px',left:'0px',width:'100%',height:$(document).height(),background:$.,opacity:$.
                });
                break;
                case'hide':$("#popup_overlay").remove();
                break
            }
        }
        ,_reposition:function(){
            var top=(($(window).height()/ 2) - ($("#popup_container").outerHeight() /2))+$.;
            var left=(($(window).width()/ 2) - ($("#popup_container").outerWidth() /2))+$.;
            if(top<0)top=0;
            if(left<0)left=0;
            if($.&&parseInt($.)<=6)top=top+$(window).scrollTop();
            $("#popup_container").css({
                top:top+'px',left:left+'px'
            });
            $("#popup_overlay").height($(document).height())
        }
        ,_maintainPosition:function(status){
            if($.){
                switch(status){
                    case true:$(window).bind('resize',function(){
                        $.alerts._reposition()
                    });
                    break;
                    case false:$(window).unbind('resize');
                    break
                }
            }
        }
    };
    jAlert=function(message,title,callback){
        $.(message,title,callback)
    }