Question

I know how to validate a single checkbox, but what if I have multiple checkboxes and I am saving those values into an array in my database? I want the user to either select one or more check boxes, which pops an alert box.

Below is a snipet of the form and the validator I use. The rest of the form validates fine. I use asp to produce multiple check boxes, but stackoverflow isnt letting display it, so just let you know there is more than one box.

HTML:

<input type="checkbox" name="j" value="<%=getcall_1_ary(jt)%>"/>

Javascript:

 if (document.addSC.j.checked == false ) {
   alert("Select Desired Job Type")
 }

Answer 1

Try this code.

<script>
    function validateCheckBoxes() 
    {
        var isValid = false;
        //alert("Check if any checkbox is not checked..."); 
        var allRows = document.getElementsByTagName("input");
        for (var i=0; i < allRows.length; i++) {
            if (allRows[i].type == 'checkbox' && allRows[i].name == '123') {
                if (allRows[i].checked == true) {
                       return true;
                }
            }
        }
        return isValid;
    }

    function submitBtn (){
        if (!validateCheckBoxes()){
            alert("no check box selected");
        }
        else 
            alert("one or more check box selected");
    }


</script>

HTML Part:

<form  method="get">
    <input type="checkbox" name="123" />
    <input type="checkbox" name="123" />
    <input type="checkbox" name="123" />
    <input type="button" value="submit" onClick="JavaScript:submitBtn();"/>
</form>

Check it now.