append() && html()

append()会重复添加!!!!!! 

 var str = "";
    $.each(msgArr,function(i,obj){      
        str += '<div class="line-part">';
            str += '<div class="line-progress">';
                str += '<span class="order-num">' + (i+1) + '</span>';
                str += '<span class="progressbar-title">'+ obj.startStations +'-'+ obj.endStations+'</span>';
            str += '</div>';
            str += '<span class="progress progress-bar">'+'</span>';
        str += '</div>';
    })
    // $(".range-part").append(str);//重复添加
    $(".range-part").html(str);