Can you change the selected row of a select box? 2

[LyndonOHRC]

I have a select dropdown where the first (and default selected) element is always blank.

If a user checks a checkbox I have on the form can the select be set back to that top element?

Lyndon

<form name="myform" me
<form name="myform" method="post" action="nextpage.cfm">
 Tax Free: 
 <input type="Checkbox" name="NoTax" onclick="if (this.checked) SetDropDownToZero()">
<br>
 Tax Rate:
 <select name="TaxRate">
  <option value="0" selected>&nbsp;</option>
  <option value="8.5">Oklahoma City</option>
  <option value="8.87">Norman</option>
 </select>
</form>

<script type="text/javascript">
 function SetDropDownToZero()
 {
  //I have no idea
 }

</script>

 

[LFI]

 function SetDropDownToZero()
 {
  [red]document.forms['myform'].elements['TaxRate'].selectedIndex = 0;[/red]
 }

I think that ought to do it.

Dave

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...east is east and west is west and if you take cranberries and stew them like applesauce
they taste much more like prunes than rhubarb does

 

[kaht]

You can set the value of a textbox both by using the .selectedIndex value (as dave showed above) or by directly setting the value of the textbox. Since we know the value of the first element of your dropdown is 0 we can set the value of the dropdown to 0 to make it jump to that option.

 function SetDropDownToZero()
 {
  document.forms['myform'].elements['TaxRate'][!].value[/!] = 0;
 }

-kaht

[small] <P> <B> <P> <B> <P> <B> <P> <B> <P> <B> <P> <B> <P> <B> <P> <B> <P> <B> <P> <B> <P> <B> <P> <B> <P> <B> <P> <.</B>[/small]
[small](He's back)[/small]

 

[LyndonOHRC]

Thanks, both solutions work great.

 

[LyndonOHRC]

I have additional information on this thread. I wanted to share it for anyone using this solution in the future.

While both solutions gave me the desired behavior while using my data entry page; each method rolled the select dropdown back to my top choice (element 0).

I ran into a problem, however, when writing my action page that demonstrated (to me) exactly how each method works.

When using solution 2 the value of Form.TaxRate was numeric zero and not the text value I had set it to in my html code.

I ran a string compare operation on it in my action page and, of course, got an error.

When using solution 1 the value of Form.TaxRate, in my action page, is the same as I had set it in my data entry page.

Thanks, hope this helps another newbie like me. :~)
Lyndon

Solution 1:

document.forms['myform'].elements['TaxRate'].selectedIndex = 0;

Solution 2:

document.forms['myform'].elements['TaxRate'].value = 0;

 

[LFI]

Good of you to post a follow-up like that!

Dave

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...east is east and west is west and if you take cranberries and stew them like applesauce
they taste much more like prunes than rhubarb does

 

[LyndonOHRC]

No problem.

About all I have to offer are the results of my errors. But I'm more than happy to share.

Lyndon