How to implement “select all” check box in HTML?

Question

I have an HTML page with multiple checkboxes.

I need one more checkbox by the name \"select all\". When I select this checkbox all checkboxes in the HTML page must b

Answer 1

This is what this will do, for instance if you have 5 checkboxes, and you click check all,it check all, now if you uncheck all the checkbox probably by clicking each 5 checkboxs, by the time you uncheck the last checkbox, the select all checkbox also gets unchecked

$("#select-all").change(function(){
   $(".allcheckbox").prop("checked", $(this).prop("checked"))
  })
  $(".allcheckbox").change(function(){
      if($(this).prop("checked") == false){
          $("#select-all").prop("checked", false)
      }
      if($(".allcheckbox:checked").length == $(".allcheckbox").length){
          $("#select-all").prop("checked", true)
      }
  })