text: /*
   * @Author: yk 
   * @Date: 2021-08-04 17:40:23 
   * @Last Modified by: yk
   * @Last Modified time: 2021-08-04 23:19:09
   */
  
  /**
   * @description modified baidu.com home html
   * 
   * add input tag to baidu.com html
   * 
   */
  function demoOne()
  {
      var oSu = document.getElementById('su'),
          oKw = document.getElementById('kw'),
          oInput = document.createElement('input')
  
      oInput.type = 'button'
      oInput.className = 'bg s_btn'
      oInput.id = 'yk'
      oInput.value = 'yk'
      // oInput.setAttribute('value', 'yk')
      oInput.style.marginTop = '15px'
      oInput.onclick = function ()
      {
          oKw.value = 'yk test'
      }
      oSu.parentElement.appendChild(oInput)
  }
  
  function demoTwo()
  {
      document.getElementById('su').setAttribute('value', 'demoTwo test')
      document.getElementById('kw').setAttribute('value', 'demoTwo')
      console.log(document.getElementById('su').value)
  }
  
  // demoTwo()
  
  function demoThree()
  {
      document.getElementById('su').value = 'demoThree'
      document.getElementById('su').setAttribute('type', 'button')
      document.getElementById('su').setAttribute('onclick', 'alert(document.getElementById("kw").value)')
  }
  
  // demoThree()
  
  /**
   * @description 自动滚动滚动条到一定位置
   * 
   */
  function demoFour()
  {
      const doc = document.documentElement
      var timer = setInterval(() =>
      {
          if (doc.scrollTop >= 500)
          {
              clearInterval(timer)
          }
          doc.scrollTop += 2
      }, 50)
  }
  
  demoFour()