根据滚动条位置更改元素的不透明度

时间:2019-11-16 12:03:55

标签: javascript jquery

我正在尝试根据滚动条的位置更改元素的不透明度,但是该功能总是会在第一个“否则”之后停止,因此元素“ C”,“ D”,“ E”,尽管该功能仍会检测滚动条位置

$(document).ready(function() {   
      $(window).scroll(function(event) {
        var scroll = $(window).scrollTop();

      if (scroll < 600) {
        document.getElementById("A").style.opacity = "1";
        document.getElementById("B").style.opacity = "0.5";
        document.getElementById("C").style.opacity = "0.5";
        document.getElementById("D").style.opacity = "0.5";
      } 
      else if (600 <= scroll < 1500) {
        document.getElementById("A").style.opacity = "0.5";
        document.getElementById("B").style.opacity = "1";
        document.getElementById("C").style.opacity = "0.5";
        document.getElementById("D").style.opacity = "0.5";
      } 
      else if (1500 <= scroll < 2600) {
        document.getElementById("A").style.opacity = "0.5";
        document.getElementById("B").style.opacity = "0.5";
        document.getElementById("C").style.opacity = "1";
        document.getElementById("D").style.opacity = "0.5";
      } 
      else if (2600 <= scroll < 3200) {
        document.getElementById("A").style.opacity = "0.5";
        document.getElementById("B").style.opacity = "0.5";
        document.getElementById("C").style.opacity = "0.5";
        document.getElementById("D").style.opacity = "1";