在Repeater控件中处理RadioButtonList中的null

Question

We have the following RadioButtonList in our Repeater control:

<asp:RadioButtonList ID="rdlmhorsepType" Text='<%#string.IsNullOrEmpty((string)Eval("rdlmhorsepType")) ? "Electric Start" : Eval("rdlmhorsepType") %>' runat="server" ValidationGroup ="stype" RepeatDirection="Horizontal" TextAlign="Right" style="display:inline;"  AutoPostBack="true" OnSelectedIndexChanged="rblPurchaseType_SelectedIndexChanged">
   <asp:ListItem Text="Electric Start" />
   <asp:ListItem Text="Recoil" />
</asp:RadioButtonList><br />

Our normal business process requires a user to enter an account number to check the existence of records associated with that account number.

If records exist, Repeater control form is populated with those records.

Users can then make whatever modifications they wish to make.

This part works great.

If no record exists, user is then required to enter his/her information and submit to the database.

This is where we are having problem.

This an issue because if no values from the rdlmhorsepType already exists on the database, the following error is raised:

'rdlmhorsepType ' has a SelectedValue which is invalid because it does not exist in the list of items. Parameter name: value

Since there are two values in the rdlmhorsepType RadioButtonList control, I used Electric Start as the default value to eliminate the error.

Problem with this is that Electric Start always gets inserted into the database and is always displayed as the selected value.

I attempted to use 0 as in:

Text='<%#string.IsNullOrEmpty((string)Eval("rdlmhorsepType")) ? "0" : Eval("rdlmhorsepType") %>' 

but it throws same error.

Any ideas how to fix this error which allows the display of the correct selected value from the database?

That error by the way, points to this database table is used for initializing DataTable values:

        dr = dt.NewRow();
        dr["RowNumber"] = 1;
        dr["rdlmhorsepType"] = string.Empty;
        dr["rblIssues"] = string.Empty;
        dr["vesseltypeUse"] = string.Empty;
        dt.Rows.Add(dr);
    }
    else
    {
        dt = (DataTable)ViewState["CurrentTable"];
    }
    //Store the DataTable in ViewState for future reference
    ViewState["CurrentTable"] = dt;
    if (dt.Rows.Count > 0)
    {
        //Bind the Repeater with the DataTable
        Repeater2.DataSource = dt;
        Repeater2.DataBind();
    }
}

Answer 1

Add Value attribute to list item like below code

 <asp:RadioButtonList ID="rdlmhorsepType" Text='<%#string.IsNullOrEmpty((string)Eval("rdlmhorsepType")) ? "Electric Start" : Eval("rdlmhorsepType") %>' runat="server" ValidationGroup ="stype" RepeatDirection="Horizontal" TextAlign="Right" style="display:inline;"  AutoPostBack="true" OnSelectedIndexChanged="rblPurchaseType_SelectedIndexChanged">
       <asp:ListItem Value="0" Text="Electric Start" />
       <asp:ListItem Value="1" Text="Recoil" />
    </asp:RadioButtonList><br />