Updating TextBoxFor when changing DropDownListFor - asp.net-mvc-3

Question

I'm using ASP MVC 3 and currently having a problem getting new data in my textboxes when I change the value of my dropdownlistfor.
<div id="BagelProductEdit">
<h2>Bagel</h2>
#Html.DropDownListFor(x => x.SelectedOptionBagel, Model.LstBagelsList, new { #class = "width200", #onchange = "refreshTextBoxFors()" })
<br />
<table>
<tr>
<td>Bagelnaam</td><td> #Html.TextBoxFor(x => x.LstBagels.ElementAt(x.SelectedOptionBagel).Name,new { Name ="txtEditBagelName" })</td>
</tr>
<tr>
<td>Vertaling</td><td> #Html.TextBoxFor(x => x.LstBagels.ElementAt(x.SelectedOptionBagel).NameFr,new { Name ="txtEditBagelNameFr" })</td>
</tr>
<tr>
<td>Prijs</td>
<td> #Html.TextBoxFor(x => x.LstBagels.ElementAt(x.SelectedOptionBagel).Price,new { Name ="txtEditBagelPrice" })</td>
</tr>
</table>
<input class="button widthorderProduct" type="submit" name="BtnEditBagel" value="Edit een bagel" />
</div>
How can I get the refreshed value in my textboxes when the value of my dropdownlist changes?

Answer 1

You can add an ID to that dropdownlist:
#Html.DropDownListFor(x => x.SelectedOptionBagel, Model.LstBagelsList, new { #class = "width200", #onchange = "refreshTextBoxFors()", id= "myDDL" })
Then, in the refreshTextBoxFors() you can access the dropdownlist selected value this way (assuming you are using jQuery):
$("#myDDL").val();
If you need the selected text (not the value):
$("#myDDL :selected").text();
In you are not using jQuery, but plain Javascript, you can use this for getting the selected value in a DropDownList:
var e = document.getElementById("myDDL");
var selValue = e.options[e.selectedIndex].value;
EDIT - To set the data of textboxes:
Once you have the DDL selected value you can do:
if(selValue == '1'){
$('#test').val('here is the value you want to put');
}
else{
$('#test').val('other value');
}
Now, in the example in your comment, it seems you have a list of TextBoxFors. So if you put an id in a loop, it will set that to all of your textboxes. You can put a #class = "test" instead and access the textboxes using $('.test') instead of $('#test').