js click the question please see

just didn't pay attention to see, are you using ajax inside. The HTML(); In this case, you need to use a delegate instead of listening directly. Your listening js should be:

const pageList = $("#page_list");
pageList.on('click', 'li.cli', function(event) {
  let  page = $(event.target).attr('data-page');
  $.ajax({
    url: "/ajax/",
    type: "GET",
    data: {'data' : page},
    dataType: "JSON",
    success: function (res) {
      if (res.status) {
        $('#cre').html(res.data);
        pageList.html(res.page)
      } else {
        alert("异常！")
      }
    }
  })
})

commented out Or useless