為什么報錯，出現Cannot read property 'length' of null at switchSlider (index.html:212) at window.onload (index.html:224)
?? ??? ??? ??? ?//5.3清除他們的active樣式
?? ??? ??? ??? ?for(i=0;i<clear_ctrl.length;i++){
?? ??? ??? ??? ??? ?clear_main[i].className = clear_main[i].className.replace('main-i_active','');
?? ??? ??? ??? ??? ?clear_ctrl[i].className = clear_ctrl[i].className.replace('ctrl-i_active','');
?? ??? ??? ??? ?}
?? ??? ??? ??? ?//5.4為當前控制按鈕和幻燈片附加樣式
?? ??? ??? ??? ?main.className += 'main-i_active';
?? ??? ??? ??? ?ctrl.className += 'ctrl-i_active';
?? ??? ??? ?}
?? ??? ??? ?
?? ??? ??? ?//4.定義何時處理幻燈片輸出
?? ??? ??? ?window.onload=function(){
?? ??? ??? ??? ?addSliders();
?? ??? ??? ??? ?switchSlider(1);
?? ??? ??? ?}
2022-11-30
原因你這個數據不是一個數組類型，