Using JS to enable/disable??

crabjoe · November 10th, 2008, 02:05 PM

Need some help because I can't find an answer using google.

I need to be able to enable/disable a select field in a form, but when disabled, I want the value set to null and the drop down grayed out.

Below is a short what I have but it doesn't work. Need a little help please..

Code:

    <script language="JavaScript">
        function ckbox(y){
            with(document.form_product){
                if(y=="1"){                    
                    document.form_prodcode.value=''; document.form_prodcode.disabled=true;
                }else if(y=="0"){
                    document.form_prodcode.disabled=false;                
                }
            }
        }
    </script>

    <form>

        INCLUDE PRODUCT INFO:
            <input type="radio" name="form_product" value = "0" onclick="ckbox(this.value);" checked>YES&nbsp;&nbsp;
            <input type="radio" name="form_product" value = "1" onclick="ckbox(this.value);">NO

        PRODUCT CODE 
            <select name="form_prodcode">
                <option value=""></option>
                <option value="A321">A321</option>
                <option value="A535">A535</option>
                <option value="B765">B765</option>
                <option value="C124">C124</option>
            </select>

    </form>

Thanks!!

dparsons · November 10th, 2008, 02:46 PM

Hmm. What is it not doing? What is the purpose of your with statement?

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crabjoe · November 10th, 2008, 03:33 PM

It's not doing anything. When I select Yes or No in the Product field, I need the Product Code drop down to either Enable itself or Disable itself. The way the code is now, it doesn't do a thing, so I need some help to fix it.

dparsons · November 10th, 2008, 05:04 PM

Your problem is that you can not use with() in this context (in reality it should of thrown you an error) as it is only used to set the properites of an object. For example:

Code:

with(someElement.style)
{
color = "black";
}

The following JavaScript will suit your needs:

Code:

    <script language="JavaScript">
        function ckbox(y){
            //with(document.form_product){
                if(y=="1"){                    
                    document.getElementById('form_prodcode').value=''; document.getElementById('form_prodcode').disabled=true;
                }else if(y=="0"){
                    document.getElementById('form_prodcode').disabled=false;                
                }
            //}
        }
    </script>

================================================== =========
Read this if you want to know how to get a correct reply for your question:
http://www.catb.org/~esr/faqs/smart-questions.html
================================================== =========
.: Wrox Technical Editor / Author :.
Wrox Books 24 x 7
================================================== =========

crabjoe · November 10th, 2008, 06:48 PM

Thanks!! Worked like a charm!