[javascript] How to implement "select all" check box in HTML?

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 be selected. How can I do this?

Below methods are very Easy to understand and you can implement existing forms in minutes

With Jquery,

$(document).ready(function() {
  $('#check-all').click(function(){
    $("input:checkbox").attr('checked', true);
  });
  $('#uncheck-all').click(function(){
    $("input:checkbox").attr('checked', false);
  });
});

in HTML form put below buttons

<a id="check-all" href="javascript:void(0);">check all</a>
<a id="uncheck-all" href="javascript:void(0);">uncheck all</a> 

With just using javascript,

<script type="text/javascript">
function checkAll(formname, checktoggle)
{
  var checkboxes = new Array(); 
  checkboxes = document[formname].getElementsByTagName('input');

  for (var i=0; i<checkboxes.length; i++)  {
    if (checkboxes[i].type == 'checkbox')   {
      checkboxes[i].checked = checktoggle;
    }
  }
}
</script>

in HTML form put below buttons

<button onclick="javascript:checkAll('form3', true);" href="javascript:void();">check all</button>

<button onclick="javascript:checkAll('form3', false);" href="javascript:void();">uncheck all</button>

that should do the job done:

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

I'm surprised no one mentioned document.querySelectorAll(). Pure JavaScript solution, works in IE9+.

function toggle(source) {_x000D_
    var checkboxes = document.querySelectorAll('input[type="checkbox"]');_x000D_
    for (var i = 0; i < checkboxes.length; i++) {_x000D_
        if (checkboxes[i] != source)_x000D_
            checkboxes[i].checked = source.checked;_x000D_
    }_x000D_
}

<input type="checkbox" onclick="toggle(this);" />Check all?<br />_x000D_
_x000D_
<input type="checkbox" />Bar 1<br />_x000D_
<input type="checkbox" />Bar 2<br />_x000D_
<input type="checkbox" />Bar 3<br />_x000D_
<input type="checkbox" />Bar 4<br />

1: Add the onchange event Handler

<th><INPUT type="checkbox" onchange="checkAll(this)" name="chk[]" /> </th>

2: Modify the code to handle checked/unchecked

 function checkAll(ele) {
     var checkboxes = document.getElementsByTagName('input');
     if (ele.checked) {
         for (var i = 0; i < checkboxes.length; i++) {
             if (checkboxes[i].type == 'checkbox') {
                 checkboxes[i].checked = true;
             }
         }
     } else {
         for (var i = 0; i < checkboxes.length; i++) {
             console.log(i)
             if (checkboxes[i].type == 'checkbox') {
                 checkboxes[i].checked = false;
             }
         }
     }
 }

You may have different sets of checkboxes on the same form. Here is a solution that selects/unselects checkboxes by class name, using vanilla javascript function document.getElementsByClassName

The Select All button

<input type='checkbox' id='select_all_invoices' onclick="selectAll()"> Select All

Some of the checkboxes to select

<input type='checkbox' class='check_invoice' id='check_123' name='check_123' value='321' />
<input type='checkbox' class='check_invoice' id='check_456' name='check_456' value='852' />

The javascript

    function selectAll() {
        var blnChecked = document.getElementById("select_all_invoices").checked;
        var check_invoices = document.getElementsByClassName("check_invoice");
        var intLength = check_invoices.length;
        for(var i = 0; i < intLength; i++) {
            var check_invoice = check_invoices[i];
            check_invoice.checked = blnChecked;
        }
    }

I'm surprised no one mentioned document.querySelectorAll(). Pure JavaScript solution, works in IE9+.

function toggle(source) {_x000D_
    var checkboxes = document.querySelectorAll('input[type="checkbox"]');_x000D_
    for (var i = 0; i < checkboxes.length; i++) {_x000D_
        if (checkboxes[i] != source)_x000D_
            checkboxes[i].checked = source.checked;_x000D_
    }_x000D_
}

<input type="checkbox" onclick="toggle(this);" />Check all?<br />_x000D_
_x000D_
<input type="checkbox" />Bar 1<br />_x000D_
<input type="checkbox" />Bar 2<br />_x000D_
<input type="checkbox" />Bar 3<br />_x000D_
<input type="checkbox" />Bar 4<br />

Here is a backbone.js implementation:

events: {
    "click #toggleChecked" : "toggleChecked"
},
toggleChecked: function(event) {

    var checkboxes = document.getElementsByName('options');
    for(var i=0; i<checkboxes.length; i++) {
        checkboxes[i].checked = event.currentTarget.checked;
    }

},

Try this simple JQuery:

$('#select-all').click(function(event) {
  if (this.checked) {
    $(':checkbox').prop('checked', true);
  } else {
    $(':checkbox').prop('checked', false);
  }
});

JavaScript is your best bet. The link below gives an example using buttons to de/select all. You could try to adapt it to use a check box, just use you 'select all' check box' onClick attribute.

Javascript Function to Check or Uncheck all Checkboxes

This page has a simpler example

http://www.htmlcodetutorial.com/forms/_INPUT_onClick.html

You can Use This code.

var checkbox = document.getElementById("dlCheckAll4Delete");
checkbox.addEventListener("click", function (event) {
  let checkboxes = document.querySelectorAll(".dlMultiDelete");
  checkboxes.forEach(function (ele) {
    ele.checked = !!checkbox.checked;
  });
});

You may have different sets of checkboxes on the same form. Here is a solution that selects/unselects checkboxes by class name, using vanilla javascript function document.getElementsByClassName

The Select All button

<input type='checkbox' id='select_all_invoices' onclick="selectAll()"> Select All

Some of the checkboxes to select

<input type='checkbox' class='check_invoice' id='check_123' name='check_123' value='321' />
<input type='checkbox' class='check_invoice' id='check_456' name='check_456' value='852' />

The javascript

    function selectAll() {
        var blnChecked = document.getElementById("select_all_invoices").checked;
        var check_invoices = document.getElementsByClassName("check_invoice");
        var intLength = check_invoices.length;
        for(var i = 0; i < intLength; i++) {
            var check_invoice = check_invoices[i];
            check_invoice.checked = blnChecked;
        }
    }

JavaScript is your best bet. The link below gives an example using buttons to de/select all. You could try to adapt it to use a check box, just use you 'select all' check box' onClick attribute.

Javascript Function to Check or Uncheck all Checkboxes

This page has a simpler example

http://www.htmlcodetutorial.com/forms/_INPUT_onClick.html

Simple and to the POINT:

jQuery - Upon Clicking a button or div or a label element. Check off all checkboxes on the page. Keep in mind you'll have to adjust :checkbox to make it more specific.

jQuery("#My-Button").click(function() {

  jQuery(':checkbox').each(function() {
    if(this.checked == true) {
      this.checked = false;                        
    } else {
      this.checked = true;                        
    }      
  });

});

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" />

JavaScript is your best bet. The link below gives an example using buttons to de/select all. You could try to adapt it to use a check box, just use you 'select all' check box' onClick attribute.

Javascript Function to Check or Uncheck all Checkboxes

This page has a simpler example

http://www.htmlcodetutorial.com/forms/_INPUT_onClick.html

<asp:CheckBox ID="CheckBox1" runat="server" Text="Select All" onclick="checkAll(this);" />
<br />
<asp:CheckBoxList ID="CheckBoxList1" runat="server">
    <asp:ListItem Value="Item 1">Item 1</asp:ListItem>
    <asp:ListItem Value="Item 2">Item 2</asp:ListItem>
    <asp:ListItem Value="Item 3">Item 3</asp:ListItem>
    <asp:ListItem Value="Item 4">Item 4</asp:ListItem>
    <asp:ListItem Value="Item 5">Item 5</asp:ListItem>
    <asp:ListItem Value="Item 6">Item 6</asp:ListItem>
</asp:CheckBoxList>

<script type="text/javascript">
    function checkAll(obj1) {
        var checkboxCollection = document.getElementById('<%=CheckBoxList1.ClientID %>').getElementsByTagName('input');

        for (var i = 0; i < checkboxCollection.length; i++) {
            if (checkboxCollection[i].type.toString().toLowerCase() == "checkbox") {
                checkboxCollection[i].checked = obj1.checked;
            }
        }
    }
</script>

As I cannot comment, here as answer: I would write Can Berk Güder's solution in a more general way, so you may reuse the function for other checkboxes

<script language="JavaScript">
  function toggleCheckboxes(source, cbName) {
    checkboxes = document.getElementsByName(cbName);
    for (var i = 0, n = checkboxes.length; i < n; i++) {
      checkboxes[i].checked = source.checked;
    }
  }
</script>

<input type="checkbox" onClick="toggleCheckboxes(this,\'foo\')" /> 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/>
<input type="checkbox" name="foo" value="bar5"> Bar 5<br/>

My simple solution allows to selectively select/deselect all checkboxes in a given portion of the form, while using different names for each checkbox, so that they can be easily recognized after the form is POSTed.

Javascript:

function setAllCheckboxes(divId, sourceCheckbox) {
    divElement = document.getElementById(divId);
    inputElements = divElement.getElementsByTagName('input');
    for (i = 0; i < inputElements.length; i++) {
        if (inputElements[i].type != 'checkbox')
            continue;
        inputElements[i].checked = sourceCheckbox.checked;
    }
}

HTML example:

<p><input onClick="setAllCheckboxes('actors', this);" type="checkbox" />All of them</p>
<div id="actors">
    <p><input type="checkbox" name="kevin" />Spacey, Kevin</p>
    <p><input type="checkbox" name="colin" />Firth, Colin</p>
    <p><input type="checkbox" name="scarlett" />Johansson, Scarlett</p>
</div>

I hope you like it!

Simple and to the POINT:

jQuery - Upon Clicking a button or div or a label element. Check off all checkboxes on the page. Keep in mind you'll have to adjust :checkbox to make it more specific.

jQuery("#My-Button").click(function() {

  jQuery(':checkbox').each(function() {
    if(this.checked == true) {
      this.checked = false;                        
    } else {
      this.checked = true;                        
    }      
  });

});

<html>

<head>
<script type="text/javascript">

    function do_this(){

        var checkboxes = document.getElementsByName('approve[]');
        var button = document.getElementById('toggle');

        if(button.value == 'select'){
            for (var i in checkboxes){
                checkboxes[i].checked = 'FALSE';
            }
            button.value = 'deselect'
        }else{
            for (var i in checkboxes){
                checkboxes[i].checked = '';
            }
            button.value = 'select';
        }
    }
</script>
</head>

<body>
<input type="checkbox" name="approve[]" value="1" />
<input type="checkbox" name="approve[]" value="2" />
<input type="checkbox" name="approve[]" value="3" />

<input type="button" id="toggle" value="select" onClick="do_this()" />
</body>

</html>

Try this simple JQuery:

$('#select-all').click(function(event) {
  if (this.checked) {
    $(':checkbox').prop('checked', true);
  } else {
    $(':checkbox').prop('checked', false);
  }
});

I'm not sure anyone hasn't answered in this way (using jQuery):

  $( '#container .toggle-button' ).click( function () {
    $( '#container input[type="checkbox"]' ).prop('checked', this.checked)
  })

It's clean, has no loops or if/else clauses and works as a charm.

JavaScript is your best bet. The link below gives an example using buttons to de/select all. You could try to adapt it to use a check box, just use you 'select all' check box' onClick attribute.

Javascript Function to Check or Uncheck all Checkboxes

This page has a simpler example

http://www.htmlcodetutorial.com/forms/_INPUT_onClick.html

$(document).ready(function() {
                $(document).on(' change', 'input[name="check_all"]', function() {
                    $('.cb').prop("checked", this.checked);
                });
            });

I'm not sure anyone hasn't answered in this way (using jQuery):

  $( '#container .toggle-button' ).click( function () {
    $( '#container input[type="checkbox"]' ).prop('checked', this.checked)
  })

It's clean, has no loops or if/else clauses and works as a charm.

Here is a backbone.js implementation:

events: {
    "click #toggleChecked" : "toggleChecked"
},
toggleChecked: function(event) {

    var checkboxes = document.getElementsByName('options');
    for(var i=0; i<checkboxes.length; i++) {
        checkboxes[i].checked = event.currentTarget.checked;
    }

},

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" />

$(document).ready(function() {
                $(document).on(' change', 'input[name="check_all"]', function() {
                    $('.cb').prop("checked", this.checked);
                });
            });

Maybe a bit late, but when dealing with a check all checkbox, I believe you should also handle the scenario for when you have the check all checkbox checked, and then unchecking one of the checkboxes below.

In that case it should automatically uncheck the check all checkbox.

Also when manually checking all the checkboxes, you should end up with the check all checkbox being automatically checked.

You need two event handlers, one for the check all box, and one for when clicking any of the single boxes below.

// HANDLES THE INDIVIDUAL CHECKBOX CLICKS
function client_onclick() {
    var selectAllChecked = $("#chk-clients-all").prop("checked");

    // IF CHECK ALL IS CHECKED, AND YOU'RE UNCHECKING AN INDIVIDUAL BOX, JUST UNCHECK THE CHECK ALL CHECKBOX.
    if (selectAllChecked && $(this).prop("checked") == false) {
        $("#chk-clients-all").prop("checked", false);
    } else { // OTHERWISE WE NEED TO LOOP THROUGH INDIVIDUAL CHECKBOXES AND SEE IF THEY ARE ALL CHECKED, THEN CHECK THE SELECT ALL CHECKBOX ACCORDINGLY.
        var allChecked = true;
        $(".client").each(function () {
            allChecked = $(this).prop("checked");
            if (!allChecked) {
                return false;
            }
        });
        $("#chk-clients-all").prop("checked", allChecked);
    }
}

// HANDLES THE TOP CHECK ALL CHECKBOX
function client_all_onclick() {
    $(".client").prop("checked", $(this).prop("checked"));
}

html

<input class='all' type='checkbox'> All
<input class='item' type='checkbox' value='1'> 1
<input class='item' type='checkbox' value='2'> 2
<input class='item' type='checkbox' value='3'> 3

javascript

$(':checkbox.all').change(function(){
  $(':checkbox.item').prop('checked', this.checked);
});

<asp:CheckBox ID="CheckBox1" runat="server" Text="Select All" onclick="checkAll(this);" />
<br />
<asp:CheckBoxList ID="CheckBoxList1" runat="server">
    <asp:ListItem Value="Item 1">Item 1</asp:ListItem>
    <asp:ListItem Value="Item 2">Item 2</asp:ListItem>
    <asp:ListItem Value="Item 3">Item 3</asp:ListItem>
    <asp:ListItem Value="Item 4">Item 4</asp:ListItem>
    <asp:ListItem Value="Item 5">Item 5</asp:ListItem>
    <asp:ListItem Value="Item 6">Item 6</asp:ListItem>
</asp:CheckBoxList>

<script type="text/javascript">
    function checkAll(obj1) {
        var checkboxCollection = document.getElementById('<%=CheckBoxList1.ClientID %>').getElementsByTagName('input');

        for (var i = 0; i < checkboxCollection.length; i++) {
            if (checkboxCollection[i].type.toString().toLowerCase() == "checkbox") {
                checkboxCollection[i].checked = obj1.checked;
            }
        }
    }
</script>

This sample works with native JavaScript where the checkbox variable name varies, i.e. not all "foo."

<!DOCTYPE html>
<html>
<body>

<p>Toggling checkboxes</p>
<script>
function getcheckboxes() {
    var node_list = document.getElementsByTagName('input');
    var checkboxes = [];
    for (var i = 0; i < node_list.length; i++) 
    {
        var node = node_list[i];
        if (node.getAttribute('type') == 'checkbox') 
        {
            checkboxes.push(node);
        }
    } 
    return checkboxes;
}
function toggle(source) {
    checkboxes = getcheckboxes();
    for (var i = 0 n = checkboxes.length; i < n; i++) 
    {
        checkboxes[i].checked = source.checked;
    }
}
</script>    

<input type="checkbox" name="foo1" value="bar1"> Bar 1<br/>
<input type="checkbox" name="foo2" value="bar2"> Bar 2<br/>
<input type="checkbox" name="foo3" value="bar3"> Bar 3<br/>
<input type="checkbox" name="foo4" value="bar4"> Bar 4<br/>

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

</body>
</html>

When you call document.getElementsByName("name"), you will get a Object. Use .item(index) to traverse all items of a Object

HTML:

<input type="checkbox" onclick="for(c in document.getElementsByName('rfile')) document.getElementsByName('rfile').item(c).checked = this.checked">

<input type=?"checkbox" name=?"rfile" value=?"/?cgi-bin/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?includes/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?misc/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?modules/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?profiles/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?scripts/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?sites/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?stats/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?themes/?">?

to make it in short-hand version by using jQuery

The select all checkbox

<input type="checkbox" id="chkSelectAll">

The children checkbox

<input type="checkbox" class="chkDel">
<input type="checkbox" class="chkDel">
<input type="checkbox" class="chkDel">

jQuery

$("#chkSelectAll").on('click', function(){
     this.checked ? $(".chkDel").prop("checked",true) : $(".chkDel").prop("checked",false);  
})

Slightly changed version which checks and unchecks respectfully

$('#select-all').click(function(event) {
        var $that = $(this);
        $(':checkbox').each(function() {
            this.checked = $that.is(':checked');
        });
    });

Maybe a bit late, but when dealing with a check all checkbox, I believe you should also handle the scenario for when you have the check all checkbox checked, and then unchecking one of the checkboxes below.

In that case it should automatically uncheck the check all checkbox.

Also when manually checking all the checkboxes, you should end up with the check all checkbox being automatically checked.

You need two event handlers, one for the check all box, and one for when clicking any of the single boxes below.

// HANDLES THE INDIVIDUAL CHECKBOX CLICKS
function client_onclick() {
    var selectAllChecked = $("#chk-clients-all").prop("checked");

    // IF CHECK ALL IS CHECKED, AND YOU'RE UNCHECKING AN INDIVIDUAL BOX, JUST UNCHECK THE CHECK ALL CHECKBOX.
    if (selectAllChecked && $(this).prop("checked") == false) {
        $("#chk-clients-all").prop("checked", false);
    } else { // OTHERWISE WE NEED TO LOOP THROUGH INDIVIDUAL CHECKBOXES AND SEE IF THEY ARE ALL CHECKED, THEN CHECK THE SELECT ALL CHECKBOX ACCORDINGLY.
        var allChecked = true;
        $(".client").each(function () {
            allChecked = $(this).prop("checked");
            if (!allChecked) {
                return false;
            }
        });
        $("#chk-clients-all").prop("checked", allChecked);
    }
}

// HANDLES THE TOP CHECK ALL CHECKBOX
function client_all_onclick() {
    $(".client").prop("checked", $(this).prop("checked"));
}

<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;
  }
}

Demo http://jsfiddle.net/H37cb/

<script type="text/javascript" src="http://code.jquery.com/jquery-latest.min.js" /></script>

<script type="text/javascript">
$(document).ready(function(){

$('input[name="all"],input[name="title"]').bind('click', function(){
var status = $(this).is(':checked');
$('input[type="checkbox"]', $(this).parent('li')).attr('checked', status);
});

});
</script>




<div id="wrapper">
 <li style="margin-top: 20px">
  <input type="checkbox" name="all" id="all" /> <label for='all'>All</label>
  <ul>
   <li><input type="checkbox" name="title" id="title_1" /> <label for="title_1"><strong>Title 01</strong></label>
    <ul>
     <li><input type="checkbox" name="selected[]" id="box_1" value="1" /> <label for="box_1">Sub Title 01</label></li>
     <li><input type="checkbox" name="selected[]" id="box_2" value="2" /> <label for="box_2">Sub Title 02</label></li>
     <li><input type="checkbox" name="selected[]" id="box_3" value="3" /> <label for="box_3">Sub Title 03</label></li>
     <li><input type="checkbox" name="selected[]" id="box_4" value="4" /> <label for="box_4">Sub Title 04</label></li>
    </ul>
   </li>
  </ul>
  <ul>
   <li><input type="checkbox" name="title" id="title_2" /> <label for="title_2"><strong>Title 02</strong></label>
    <ul>
     <li><input type="checkbox" name="selected[]" id="box_5" value="5" /> <label for="box_5">Sub Title 05</label></li>
     <li><input type="checkbox" name="selected[]" id="box_6" value="6" /> <label for="box_6">Sub Title 06</label></li>
     <li><input type="checkbox" name="selected[]" id="box_7" value="7" /> <label for="box_7">Sub Title 07</label></li>
    </ul>
   </li>
  </ul>
 </li>
</div>

You can use this simple code

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

As I cannot comment, here as answer: I would write Can Berk Güder's solution in a more general way, so you may reuse the function for other checkboxes

<script language="JavaScript">
  function toggleCheckboxes(source, cbName) {
    checkboxes = document.getElementsByName(cbName);
    for (var i = 0, n = checkboxes.length; i < n; i++) {
      checkboxes[i].checked = source.checked;
    }
  }
</script>

<input type="checkbox" onClick="toggleCheckboxes(this,\'foo\')" /> 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/>
<input type="checkbox" name="foo" value="bar5"> Bar 5<br/>

1: Add the onchange event Handler

<th><INPUT type="checkbox" onchange="checkAll(this)" name="chk[]" /> </th>

2: Modify the code to handle checked/unchecked

 function checkAll(ele) {
     var checkboxes = document.getElementsByTagName('input');
     if (ele.checked) {
         for (var i = 0; i < checkboxes.length; i++) {
             if (checkboxes[i].type == 'checkbox') {
                 checkboxes[i].checked = true;
             }
         }
     } else {
         for (var i = 0; i < checkboxes.length; i++) {
             console.log(i)
             if (checkboxes[i].type == 'checkbox') {
                 checkboxes[i].checked = false;
             }
         }
     }
 }

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)
      }
  })

To make it deselect:

$('#select_all').click(function(event) {
  if(this.checked) {
      // Iterate each checkbox
      $(':checkbox').each(function() {
          this.checked = true;
      });
  }
  else {
    $(':checkbox').each(function() {
          this.checked = false;
      });
  }
});

You can Use This code.

var checkbox = document.getElementById("dlCheckAll4Delete");
checkbox.addEventListener("click", function (event) {
  let checkboxes = document.querySelectorAll(".dlMultiDelete");
  checkboxes.forEach(function (ele) {
    ele.checked = !!checkbox.checked;
  });
});

that should do the job done:

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

<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;
  }
}

<html>

<head>
<script type="text/javascript">

    function do_this(){

        var checkboxes = document.getElementsByName('approve[]');
        var button = document.getElementById('toggle');

        if(button.value == 'select'){
            for (var i in checkboxes){
                checkboxes[i].checked = 'FALSE';
            }
            button.value = 'deselect'
        }else{
            for (var i in checkboxes){
                checkboxes[i].checked = '';
            }
            button.value = 'select';
        }
    }
</script>
</head>

<body>
<input type="checkbox" name="approve[]" value="1" />
<input type="checkbox" name="approve[]" value="2" />
<input type="checkbox" name="approve[]" value="3" />

<input type="button" id="toggle" value="select" onClick="do_this()" />
</body>

</html>

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"/>

You can use this simple code

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

My simple solution allows to selectively select/deselect all checkboxes in a given portion of the form, while using different names for each checkbox, so that they can be easily recognized after the form is POSTed.

Javascript:

function setAllCheckboxes(divId, sourceCheckbox) {
    divElement = document.getElementById(divId);
    inputElements = divElement.getElementsByTagName('input');
    for (i = 0; i < inputElements.length; i++) {
        if (inputElements[i].type != 'checkbox')
            continue;
        inputElements[i].checked = sourceCheckbox.checked;
    }
}

HTML example:

<p><input onClick="setAllCheckboxes('actors', this);" type="checkbox" />All of them</p>
<div id="actors">
    <p><input type="checkbox" name="kevin" />Spacey, Kevin</p>
    <p><input type="checkbox" name="colin" />Firth, Colin</p>
    <p><input type="checkbox" name="scarlett" />Johansson, Scarlett</p>
</div>

I hope you like it!

If adopting the top answer for jQuery, remember that the object passed to the click function is an EventHandler, not the original checkbox object. Therefore code should be modified as follows.

HTML

<input type="checkbox" name="selectThemAll"/> 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/>

Javascript

$(function() {
    jQuery("[name=selectThemAll]").click(function(source) { 
        checkboxes = jQuery("[name=foo]");
        for(var i in checkboxes){
            checkboxes[i].checked = source.target.checked;
        }
    });
})

Below methods are very Easy to understand and you can implement existing forms in minutes

With Jquery,

$(document).ready(function() {
  $('#check-all').click(function(){
    $("input:checkbox").attr('checked', true);
  });
  $('#uncheck-all').click(function(){
    $("input:checkbox").attr('checked', false);
  });
});

in HTML form put below buttons

<a id="check-all" href="javascript:void(0);">check all</a>
<a id="uncheck-all" href="javascript:void(0);">uncheck all</a> 

With just using javascript,

<script type="text/javascript">
function checkAll(formname, checktoggle)
{
  var checkboxes = new Array(); 
  checkboxes = document[formname].getElementsByTagName('input');

  for (var i=0; i<checkboxes.length; i++)  {
    if (checkboxes[i].type == 'checkbox')   {
      checkboxes[i].checked = checktoggle;
    }
  }
}
</script>

in HTML form put below buttons

<button onclick="javascript:checkAll('form3', true);" href="javascript:void();">check all</button>

<button onclick="javascript:checkAll('form3', false);" href="javascript:void();">uncheck all</button>

html

<input class='all' type='checkbox'> All
<input class='item' type='checkbox' value='1'> 1
<input class='item' type='checkbox' value='2'> 2
<input class='item' type='checkbox' value='3'> 3

javascript

$(':checkbox.all').change(function(){
  $(':checkbox.item').prop('checked', this.checked);
});

Slightly changed version which checks and unchecks respectfully

$('#select-all').click(function(event) {
        var $that = $(this);
        $(':checkbox').each(function() {
            this.checked = $that.is(':checked');
        });
    });

This sample works with native JavaScript where the checkbox variable name varies, i.e. not all "foo."

<!DOCTYPE html>
<html>
<body>

<p>Toggling checkboxes</p>
<script>
function getcheckboxes() {
    var node_list = document.getElementsByTagName('input');
    var checkboxes = [];
    for (var i = 0; i < node_list.length; i++) 
    {
        var node = node_list[i];
        if (node.getAttribute('type') == 'checkbox') 
        {
            checkboxes.push(node);
        }
    } 
    return checkboxes;
}
function toggle(source) {
    checkboxes = getcheckboxes();
    for (var i = 0 n = checkboxes.length; i < n; i++) 
    {
        checkboxes[i].checked = source.checked;
    }
}
</script>    

<input type="checkbox" name="foo1" value="bar1"> Bar 1<br/>
<input type="checkbox" name="foo2" value="bar2"> Bar 2<br/>
<input type="checkbox" name="foo3" value="bar3"> Bar 3<br/>
<input type="checkbox" name="foo4" value="bar4"> Bar 4<br/>

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

</body>
</html>

to make it in short-hand version by using jQuery

The select all checkbox

<input type="checkbox" id="chkSelectAll">

The children checkbox

<input type="checkbox" class="chkDel">
<input type="checkbox" class="chkDel">
<input type="checkbox" class="chkDel">

jQuery

$("#chkSelectAll").on('click', function(){
     this.checked ? $(".chkDel").prop("checked",true) : $(".chkDel").prop("checked",false);  
})

<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;
  }
}

To make it deselect:

$('#select_all').click(function(event) {
  if(this.checked) {
      // Iterate each checkbox
      $(':checkbox').each(function() {
          this.checked = true;
      });
  }
  else {
    $(':checkbox').each(function() {
          this.checked = false;
      });
  }
});

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)
      }
  })

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"/>

If adopting the top answer for jQuery, remember that the object passed to the click function is an EventHandler, not the original checkbox object. Therefore code should be modified as follows.

HTML

<input type="checkbox" name="selectThemAll"/> 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/>

Javascript

$(function() {
    jQuery("[name=selectThemAll]").click(function(source) { 
        checkboxes = jQuery("[name=foo]");
        for(var i in checkboxes){
            checkboxes[i].checked = source.target.checked;
        }
    });
})

When you call document.getElementsByName("name"), you will get a Object. Use .item(index) to traverse all items of a Object

HTML:

<input type="checkbox" onclick="for(c in document.getElementsByName('rfile')) document.getElementsByName('rfile').item(c).checked = this.checked">

<input type=?"checkbox" name=?"rfile" value=?"/?cgi-bin/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?includes/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?misc/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?modules/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?profiles/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?scripts/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?sites/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?stats/?">?
<input type=?"checkbox" name=?"rfile" value=?"/?themes/?">?

Demo http://jsfiddle.net/H37cb/

<script type="text/javascript" src="http://code.jquery.com/jquery-latest.min.js" /></script>

<script type="text/javascript">
$(document).ready(function(){

$('input[name="all"],input[name="title"]').bind('click', function(){
var status = $(this).is(':checked');
$('input[type="checkbox"]', $(this).parent('li')).attr('checked', status);
});

});
</script>




<div id="wrapper">
 <li style="margin-top: 20px">
  <input type="checkbox" name="all" id="all" /> <label for='all'>All</label>
  <ul>
   <li><input type="checkbox" name="title" id="title_1" /> <label for="title_1"><strong>Title 01</strong></label>
    <ul>
     <li><input type="checkbox" name="selected[]" id="box_1" value="1" /> <label for="box_1">Sub Title 01</label></li>
     <li><input type="checkbox" name="selected[]" id="box_2" value="2" /> <label for="box_2">Sub Title 02</label></li>
     <li><input type="checkbox" name="selected[]" id="box_3" value="3" /> <label for="box_3">Sub Title 03</label></li>
     <li><input type="checkbox" name="selected[]" id="box_4" value="4" /> <label for="box_4">Sub Title 04</label></li>
    </ul>
   </li>
  </ul>
  <ul>
   <li><input type="checkbox" name="title" id="title_2" /> <label for="title_2"><strong>Title 02</strong></label>
    <ul>
     <li><input type="checkbox" name="selected[]" id="box_5" value="5" /> <label for="box_5">Sub Title 05</label></li>
     <li><input type="checkbox" name="selected[]" id="box_6" value="6" /> <label for="box_6">Sub Title 06</label></li>
     <li><input type="checkbox" name="selected[]" id="box_7" value="7" /> <label for="box_7">Sub Title 07</label></li>
    </ul>
   </li>
  </ul>
 </li>
</div>