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

You can use this simple code

$('.checkall').click(function(){
    var checked = $(this).prop('checked');
    $('.checkme').prop('checked', checked);
});

Answer 2

<script language="JavaScript">
function toggle(source) {
  checkboxes = document.getElementsByName('foo');
  for(var checkbox in checkboxes)
    checkbox.checked = source.checked;
}
</script>

<input type="checkbox" onClick="toggle(this)" /> Toggle All<br/>

<input type="checkbox" name="foo" value="bar1"> Bar 1<br/>
<input type="checkbox" name="foo" value="bar2"> Bar 2<br/>
<input type="checkbox" name="foo" value="bar3"> Bar 3<br/>
<input type="checkbox" name="foo" value="bar4"> Bar 4<br/>

UPDATE:

The for each...in construct doesn't seem to work, at least in this case, in Safari 5 or Chrome 5. This code should work in all browsers:

function toggle(source) {
  checkboxes = document.getElementsByName('foo');
  for(var i=0, n=checkboxes.length;i<n;i++) {
    checkboxes[i].checked = source.checked;
  }
}

Answer 3

Using jQuery:

// Listen for click on toggle checkbox
$('#select-all').click(function(event) {   
    if(this.checked) {
        // Iterate each checkbox
        $(':checkbox').each(function() {
            this.checked = true;                        
        });
    } else {
        $(':checkbox').each(function() {
            this.checked = false;                       
        });
    }
});

HTML:

<input type="checkbox" name="checkbox-1" id="checkbox-1" />
<input type="checkbox" name="checkbox-2" id="checkbox-2" />
<input type="checkbox" name="checkbox-3" id="checkbox-3" />

<!-- select all boxes -->
<input type="checkbox" name="select-all" id="select-all" />

Answer 4

Using jQuery and knockout:

With this binding main checkbox stays in sync with underliying checkboxes, it will be unchecked unless all checkboxes checked.

ko.bindingHandlers.allChecked = {
  init: function (element, valueAccessor) {
    var selector = valueAccessor();

    function getChecked () {
      element.checked = $(selector).toArray().every(function (checkbox) {
        return checkbox.checked;
      });
    }

    function setChecked (value) {
      $(selector).toArray().forEach(function (checkbox) {
        if (checkbox.checked !== value) {
          checkbox.click();
        }
      });
    }

    ko.utils.registerEventHandler(element, 'click', function (event) {
      setChecked(event.target.checked);
    });

    $(window.document).on('change', selector, getChecked);

    ko.utils.domNodeDisposal.addDisposeCallback(element, () => {
      $(window.document).off('change', selector, getChecked);
    });

    getChecked();
  }
};

in html:

<input id="check-all-values" type="checkbox" data-bind="allChecked: '.checkValue'"/>
<input id="check-1" type="checkbox" class="checkValue"/>
<input id="check-2" type="checkbox" class="checkValue"/>

Answer 5

that should do the job done:

    $(':checkbox').each(function() {
        this.checked = true;                        
    });