how to validate checkbox list in asp.net controls using javascript validation

function validate(source, arguments) {
           arguments.IsValid = false;
 
           var checklist = document.getElementById("MyCheckBoxList");
           if (checklist == null) return;
 
           var elements = checklist.getElementsByTagName("INPUT");
           if (elements == null) return;
 
           var checkBoxCount = 0;
           for (i = 0; i < elements.length; i++) {
               if (elements[i].checked) checkBoxCount++;
           }
           arguments.IsValid = (checkBoxCount > 0);
       }

<asp:CustomValidator ID="CustomValidator1" runat="server"
            ClientValidationFunction="validate" ErrorMessage="One of the checkboxes needs to be checked!"
            ValidationGroup=""></asp:CustomValidator>

 
Write the bellow code with in validation funtion in javascript
var chkControl= document.getElementById("<%chk.ClientID%>"); 
 
if(!chkControl.checked )
{
alert("Required to Check!!")
}

if ( form.terms.checked == false ) 
{ 
       alert ( "Please check the Conditions box." ); 
       return false; 
}

function validateform() {
            if (document.getElementById("chkChequePicked").checked == true) {
                if (document.getElementById('txtChequePickedDate').value == "" || document.getElementById('txtChequePickedDate').value == "--Just Click--") {
                    alert('Please Enter Cheque Picked Date');
                    return false;
                }
            }
            else {
                if (document.getElementById('txtChequePickedDate').value != "") {
                    alert('Please check Cheque Picked');
                    return false;
                }
                ValidatorEnable(document.getElementById("RequiredFieldValidator4"), true);
            }
 
            if (document.getElementById("chkChequeReceived").checked == true) {
                if (document.getElementById('txtChequeReceivedDate').value == "" || document.getElementById('txtChequeReceivedDate').value == "--Just Click--") {
                    alert('Please Enter Cheque Received Date');
                    return false;
                }
            }
            else {
                if (document.getElementById('txtChequeReceivedDate').value != "") {
                    alert('Please check Cheque Received');
                    return false;
                }
                ValidatorEnable(document.getElementById("RequiredFieldValidator5"), true);
            }
 
            if (document.getElementById("chkChequeDeposit").checked == true) {
                if (document.getElementById('txtChequeDepositDate').value == "" || document.getElementById('txtChequeDepositDate').value == "--Just Click--") {
                    alert('Please Enter Cheque Deposite Date');
                    return false;
                }
            }
            else {
                if (document.getElementById('txtChequeDepositDate').value != "") {
                    alert('Please check Cheque Deposite');
                    return false;
                }
                ValidatorEnable(document.getElementById("RequiredFieldValidator6"), true);
            }
            if (document.getElementById("chkChequeCleared").checked == true) {
                if (document.getElementById('txtChequeClearedDate').value == "" || document.getElementById('txtChequeClearedDate').value == "--Just Click--") {
                    alert('Please Enter Cheque Cleared Date');
                    return false;
                }
            }
            else {
                if (document.getElementById('txtChequeClearedDate').value != "") {
                    alert('Please check Cheque Cleared');
                    return false;
                }
                ValidatorEnable(document.getElementById("RequiredFieldValidator7"), true);
            }
 
            if (document.getElementById("chkChequeRemittance").checked == true) {
                if (document.getElementById('txtChequeRemittanceDate').value == "" || document.getElementById('txtChequeRemittanceDate').value == "--Just Click--") {
                    alert('Please Enter Cheque Remittance Date');
                    return false;
                }
            }
            else {
                if (document.getElementById('txtChequeRemittanceDate').value != "") {
                    alert('Please check Cheque Remittance');
                    return false;
                }
                ValidatorEnable(document.getElementById("RequiredFieldValidator8"), true);
            }
            return true;
        }