SelectedValue which is invalid because it does not exist in the list of items.
 

Hello,

Especially Phillip. I am desparately trying to implement cascading dropdowns with in a gridview. However I can not even get past the basics.

Here is the error I get. I am using the pubs database.
'ddlCountry' has a SelectedValue which is invalid because it does not exist in the list of items.
Parameter name: value

Please advise. Thanks, far

Here is my code:

<asp:ObjectDataSource ID="odsPublishers" runat="server" OldValuesParameterFormatString="original_{0}"
SelectMethod="GetPublishers" TypeName="PubsTableAdapters.PublishersTableAdapter "></asp:ObjectDataSource>

</div>
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
DataSourceID="odsPublishers" AllowPaging="True" AllowSorting="True" DataKeyNames="pub_id">
<Columns>
<asp:TemplateField HeaderText="Commands">
<ItemTemplate>
<asp:LinkButton CommandName="Edit" ID="btnEdit" runat="server" Text="Edit"></asp:LinkButton>
</ItemTemplate>
<EditItemTemplate>
<asp:LinkButton CommandName="Update" ID="btnUpdate" runat="server" Text="Update"></asp:LinkButton>
<asp:LinkButton CommandName="Cancel" ID="btnCancel" runat="server" Text="Cancel"></asp:LinkButton>
</EditItemTemplate>
</asp:TemplateField>


<asp:BoundField DataField="pub_id" HeaderText="pub_id" ReadOnly="True" SortExpression="pub_id" />
<asp:BoundField DataField="pub_name" HeaderText="pub_name" SortExpression="pub_name" />

<asp:BoundField DataField="country" HeaderText="country" SortExpression="country" />
<asp:TemplateField HeaderText="Country">
<ItemTemplate>
<asp:Label ID="lblCountry" runat="server" Text='<%#Eval("Country") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:ObjectDataSource ID="odsCountry" runat="server" OldValuesParameterFormatString="original_{0}"
SelectMethod="GetCountry" TypeName="PubsTableAdapters.pubCountryTableAdapter "></asp:ObjectDataSource>
<asp:DropDownList ID="ddlCountry" runat="server" DataSourceID="odsCountry" AutoPostBack="True"
SelectedValue='<%# Bind("Country") %>'>
</asp:DropDownList>
</EditItemTemplate>
</asp:TemplateField>

<asp:BoundField DataField="state" HeaderText="state" SortExpression="state" />
</Columns>
</asp:GridView>

I have gone throught that problem as well.

just simply do something like this:

<asp:DropDownList ID="ddlCountry" runat="server" DataSourceID="odsCountries"
AutoPostBack="True"
SelectedValue='<%# Bind("Country") %>'
AppendDataBoundItems="true">
<asp:ListItem Value="">Select a Country</asp:ListItem>
<asp:ListItem Value="">Your invalid data</asp:ListItem>
<asp:ListItem Value="">Your invalid data</asp:ListItem>
</asp:DropDownList>

OR

Fix up your database don't allow nulls.

However, I need your help.

I do the same things but whatever my dropdown value is chosen, it won't update my database. Can you suggest me a solution why?

Thanks,
Gary

Try This!
 

When I had this error message, it drove me nuts for solid day! Here's what I learned:

If you're receiving this error, then an Eval("something") or Bind("something") is referencing a database column that is empty. Manually enter some data (using SQL Server Management Studio, perhaps), and see if the error doesn't go away.\

Hope this helps. Good luck!!

Call only once
 

I got same problem too. I had used a function to Bind drop down list. But i got that i was calling that function two times and i think due to calling two times, i was facing that error. Then i call that function only once and error resolved. If any one got better option then pls reply.

Solution
 

Hi,

While you should make sure that your data structure minimises the occurance of this situation, there are situations where it is unavoidable.

I've detailed a solution which basically checks your data before binding the dropdownlist here:

http://blog.evonet.com.au/post/2008/...-of-items.aspx

Cheers,
Bartek

Try to add an UNION at your SQL SELECT phrase which populate your DropDownList:
SELECT GroupeID, Groupe FROM [Groupe]
union select '', ''

This will give you an empty row for avoiding the error.