JavaScript Forum

**Skeddles** · 11-08-2009, 02:37 PM

I just need to set the value of the currently selected option of a dropdown box.

HTML Code:

<html>
<body>

<script type="text/javascript">
function getRare()
{alert(document.myForm.rarity.options[rarity.selectedIndex].value);
}
</script>

<form name="myForm">
<select name="Rarity">
    <option value="0">Common</option>
    <option value="1">Uncommon</option>
    <option value="2">Rare</option>
    <option value="3">Other</option>
</select>
<input type="button" value="pick" onclick="getRare();" />
</form>

</body>
</html>

can you tell me what's wrong?

**chrishirst** · 11-08-2009, 02:59 PM

No idea.
What does it do, or not?

**Skeddles** · 11-08-2009, 03:29 PM

An alert should pop up saying either 0 1 2 or 3, but nothing happens...

This isn't my actual code, I'm trying to do some ajax, but I cut out all the other stuff to make it easier.

**chrishirst** · 11-08-2009, 03:34 PM

Why not just use the onchange event of the select element?

**tripy** · 11-08-2009, 03:39 PM

2 things are wrong:
1) Javascript is case sensitive. If your <select> is named Rarity, form.rarity is not the same.
2) When you look up the selectedIndex value, you have to give the full path to it.

Code:

document.myForm.rarity.options[rarity.selectedIndex]

should be

Code:

document.myForm.rarity.options[document.myForm.rarity.selectedIndex]

HTML Code:

<html>
<body>

<script type="text/javascript">
function getRare(){
  frm=document.myForm
  val=frm.Rarity.options[frm.Rarity.selectedIndex].value
  alert(val);
}
</script>

<form name="myForm">
<select name="Rarity">
    <option value="0">Common</option>
    <option value="1">Uncommon</option>
    <option value="2">Rare</option>
    <option value="3">Other</option>
</select>
<input type="button" value="pick" onclick="getRare();" />
</form>

</body>
</html>

**Skeddles** · 03:47 PM

because what the ajax is doing is submitting all the form data and adding a row to a database with php, so it has to be done all at once, and I dunno how to do post with ajax, so I'm just doing

Code:

varNumber = document.myForm.number.value;
varName = document.myForm.name.value;
xmlhttp.open("GET","addcard.php?number="+varNumber+"&name="+varName,true);
xmlhttp.send(null);

which works fine for textboxes, but not with dropdowns

EDIT: thanks tripy
I always forget about case sensitive ><

**chrishirst** · 11-08-2009, 04:23 PM

POSTing with AJAX is similar to get, you have to send the parameters length as well

http://www.openjs.com/articles/ajax_...using_post.php

**Skeddles** · 11-09-2009, 08:13 PM

I'll check it out, but at the moment it isn't needed, considering I'm just doing short text fields.

And if I wanted to do another ajax thing on the same page, should I make a whole other ajax function, or make that one work for both(with if statements?)?

And how should I go about retrieving multiple pieces of data? Like I want to make another for editing, so I'd have to load each thing and then put them into the form, but loading it 4 times seems ridiculous.