/**
 *
 * 解决 ios10 及以上 Safari 无法禁止缩放的问题
 * */
function handleUserNoScalable() {
  window.onload = function() {
    // 阻止双击放大
    var lastTouchEnd = 0
    document.addEventListener('touchstart', function(event) {
      if (event.touches.length > 1) {
        event.preventDefault()
      }
    })
    document.addEventListener(
      'touchend',
      function(event) {
        var now = new Date().getTime()
        if (now - lastTouchEnd <= 300) {
          event.preventDefault()
        }
        lastTouchEnd = now
      },
      false
    )
    // 阻止双指放大
    document.addEventListener('gesturestart', function(event) {
      event.preventDefault()
    })
  }
}