All checkboxes belong to a checkbox group.

requirement:    1.When None is checked , other checkboxes should be unchecked

                            2.When any other checkbox is checked, None should be unchecked

To achieve this I have used following Client Side Java Script code in onclick event of the checkbox group.

The 1st requirement is achieved ,but to achieve 2nd I need some condition to use if-else statement.

and put 1st block under if statement and 2nd block under else.

Is there any way to achieve this?

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var elements = document.getElementsByName("#{id:chkBoxGrpAudit}");

1st block

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//If none is checked, uncheck other check boxes
if (elements[0].checked == true) {
    for (var i = 1; i < elements.length; i++) {
        elements[i].checked = false;   
    }  
}
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2nd block

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//If any other checkbox is checked, uncheck none
for (var i = 1; i < elements.length; i++) {

    if (elements[i].checked == true) {
        elements[0].checked = false;
    }
}

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