jquery javascript 回到顶部功能

今天搞了一个回到顶部的JS JQ功能

(function($){
$.fn.survey=function(options){

var defaults={"298",height:"207"};

var options=$.extend(defaults,options);

    if($.browser.msie){
    var ieVersion=parseInt($.browser.version)}

//建立HTML
var __feedCreat=function(){
    var feedHtml=$('<div id="pubFeedBack"></div>');
    feedHtml.html('<a href="#top" id="backTop"><i></i>u8fd4u56deu9876u90e8</a><a href="#" id="callSurvey"><i></i>u610fu89c1u53cdu9988</a>');
    $("body").append(feedHtml);
    __ie6Fixed()
    };

//绑定事件
var __initEvent=function(){
    $(window).resize(function(){
    var winW=$(this).width();
    if(winW<=1124){$("#pubFeedBack").hide()}
    else{$("#pubFeedBack").show()}
    });

    $(window).bind("scroll",function(){
    if($(this).scrollTop()>50){
    $("#backTop").fadeIn().css({"display":"block"})
    }
    else{$("#backTop").fadeOut().css({"display":""})}
    });



    $("#backTop").bind("click",function(e){
    e.preventDefault();
    $("html,body").scrollTop(0)});
};

//回到顶部
var __tip=function(type,tipText){
var surveyTip=$("#D_SurveyTip"),surveyMask=$("#D_SurveyMask");
if(!surveyTip||!surveyMask){return}
surveyTip.removeClass("warning success").addClass(type).html(tipText);
surveyMask.css("display","block");
surveyTip.css("display","block");
setTimeout(function(){
surveyMask.css("display","none");                                                                                                                                                                                                                                                                                       surveyTip.css("display","none")},1000)
};


//ie6兼容
var __ie6Fixed=function(){
    if(ieVersion!==6){return}
    var surveyBox=$("#D_SurveyBox");
    var pubFeedBack=$("#pubFeedBack");
    if(!surveyBox||!pubFeedBack)
    {
        return
    }
    $(window).bind("scroll",function(){
    var h=$(window).height(),st=$(window).scrollTop(),_top=h+st-options.height;                                                                                                                                                         var _top1=h+st-pubFeedBack.height()-15;surveyBox.css("top",_top+"px");
    pubFeedBack.css("top",_top1+"px")
    })
};


//开始执行
if(screen.width>=1280)
{
    (function(){
    __feedCreat();                                                                                                                                          __initEvent()                                                                                                                                                       })()
}
}
})(jQuery);

window.onerror=function(){return false};
if($.isFunction($(document).survey)){$(document).survey()}

#backTop i,#callSurvey i{background:url(survey.png) no-repeat;}
#pubFeedBack{position:fixed;_position:absolute;right:15px;bottom:15px;54px;font-size:12px;}
#backTop,#callSurvey{display:block;52px;padding:1px;height:56px;line-height:22px;text-align:center;color:#fff;text-decoration:none;}
#backTop{display:none;background:#999;}
#backTop:hover{background:#ccc;zoom:1;text-decoration:none;color:#fff;}
#backTop i{display:block;25px;height:13px;margin:14px auto 8px;background-position:-63px 0;}
#callSurvey{margin-top:1px;background:#3687d9;}
#callSurvey:hover{background:#66a4e3;zoom:1;text-decoration:none;color:#fff;}
#callSurvey i{display:block;26px;height:25px;margin:9px auto 0;background-position:0 0;}
#callSurvey:hover i{background-position:-30px 0;}