SOURCE

// container - 父容器，如 document.getElementById('profile')
// inputClassName - 可获得焦点的 input 元素类名，如 'input-box'
const blur = (container, inputClassName) => {
  if (container.length) {
    container = container[0]
  }
  const isIOS = /iPhone|iPad|iPod|IOS/i.test(window.navigator.userAgent)
  container.addEventListener('touchend', (e) => {
    const inputElems = document.getElementsByClassName(inputClassName)
    const activeElem = document.activeElement
    for (const elem of inputElems) {
      if (e.target !== elem && elem === activeElem) {
        // 解决 IOS 微信浏览器在文本框失去焦点时，页面不会回弹的问题
        // https://blog.csdn.net/yanzhi_2016/article/details/84942569
        if (isIOS && !elem.hasBlurHandler) {
          elem.hasBlurHandler = true // 确保文本框只会监听一次 blur 事件
          elem.addEventListener('blur', () => {
            const scrollTop = document.documentElement.scrollTop || document.body.scrollTop
            window.scrollTo(0, scrollTop + 1) // 页面向下滚动
          })
        }
        elem.blur()
        break
      }
    }
  })
}