selecting all in html code example

Example 1: select all checkboxes html js

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

Example 2: when i click on one checkbox check all checkboxes

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;
    }
}