function CheckAtleastOneisChecked(checkBox) { var frm = document.forms[0]; var flag = false; var cnt = 0; for (var i = 0; i < document.forms[0].length; i++) { if (document.forms[0].elements[i].id.indexOf(checkBox) != -1) { if (document.forms[0].elements[i].checked) { flag = true cnt = cnt + 1; } } } if (flag == false) { alert('Atleast one check box should be checked.') return false }
}
Read more: http://feeds.dzone.com/~r/dzone/snippets/~3/JxxbnShP2uw/14489