点击字母滚动到对应位置

效果图

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一、代码

	    btn_letters(e, index) {
      //点击省份首字母
      // this.address=e.target.innerHTML
      var LetterList_Dom = document.getElementsByClassName("city-item");
      var LetterList_Dom_height = [];
      for (var a = 0; a < LetterList_Dom.length; a++) {
        LetterList_Dom_height.push({ height: LetterList_Dom[a].offsetHeight });
      }
      var scrollTop = 0;
      for (var b = 0; b < index; b++) {
        scrollTop += LetterList_Dom_height[b].height;
      }
      if (index >= 1) {
        scrollTop = scrollTop;
      }
      var scrollYTop = document.getElementsByClassName("scroll-y");
      scrollYTop[0].scrollTop = scrollTop;
    },

总结

提示：做个纪录。