我怎样才能 select 随机数量的复选框？

Question

    $('#select_all').on('click', function () {
        if (this.checked) {
            $('.check').each(function () {
                this.checked = true;
            });
        } else {
            $('.check').each(function () {
                this.checked = false;
            });
        }
    });
    $('.check').on('click', function () {

        if ($('.check:checked').length == $('.check').length) {
            $('#select_all').prop('checked', true);
        } else {
            $('#select_all').prop('checked', false);
        }
    });

Need to alter this above Select All code to only select some random amount of check boxes, like below code example. Any help for this?

$(".random-pick").click(function() {
  var maxAllowed = 6;
  // Count checkboxes
  var random_checkboxes = $("#content_subscribtion_ input.checkbox").size();
  // Check random checkboxes until "maxAllowed" limit reached
  while ($("#content_subscribtion_ input.checkbox:checked").size() < maxAllowed) {
    // Pick random checkbox
    var random_checkbox = Math.floor(Math.random() * random_checkboxes) + 1;
    // Check it
    $("#content_subscribtion_ input.checkbox:nth-child(" + random_checkbox + ")").prop("checked", true);
  }

  return false;
});

Answer 1

Using this tidy little shuffle method , we can create a random array of checkbox indexes, then slice it to a random number. We can then iterate and use jQuery's get() to find the checkbox index in the randomized array to check.

 Array.prototype.shuffle = function() { let m = this.length, i; while (m) { i = (Math.random() * m--) >>> 0; [this[m], this[i]] = [this[i], this[m]] } return this; } $('#select_all').on('click', function() { if ($(this).prop('checked')) { let minnum = 3, maxnum = 6 let rand = Math.min(maxnum, Math.floor(Math.random() * ($('.check').length - 1 - minnum)) + minnum) //create our keys array let keyArray = [...Array($('.check').length).keys()].shuffle().slice(0, rand) keyArray.forEach((chk_i, i) => { if (i < rand) $($('.check').get(chk_i)).prop('checked', true) }) } else { $('.check').prop('checked', false); } });

 <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <label>Select all <input type='checkbox' id="select_all"></label> <div class='cb'> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> <input type='checkbox' class='check'> checkbox <br /> </div>

Answer 2

I have 8 checkboxes on the UI and I am selecting 3 checkboxes randomly. After each run, different checkboxes will be selected. Please use the exact/clean/proper checkbox common unique identifier in the cy.get('xxxxxx') and use following code in JS:

cy.get('section[class="table-body-cell checkbox-cell grid-1"] input')
  .then(
    ($items) => {
      return Cypress._.sampleSize($items.toArray(), 3)
    })
  .check({force: true});