How to bind the selected value of a DropDownList

Data binding is all about declarative code, right? So I specify what I want with attributes, and the framework takes care of the rest. Unless I’m mistaken and data binding relates to S&M, right?

So, why does the DropDownList control only provide binding fields for its data source, i.e. its list source, and not for its actual data field. i.e. how the heck to I bind the selected value my name DropDownList to the Name field in my Person record? Is this a gross oversight on Microsoft’s part, or on mine?

What is the point of two way data binding if I still have to manually set and read the selected value?

Answers:

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Method 1

You might want to do something like the code below.
You can not set the “SelectedValue” declaratively, but by saying
“SelectedValue=<%# [code here] %> you are effectively causing the value to be set when the control is data bound.

<asp:DropDownList
                ID="DropDownInfoSource"
                runat="server"
                DataSourceID="_employeeDataSource"
                DataTextField="EmployeeName"
                DataValueField="EmployeeID"
                SelectedValue='<%# Bind("EmployeeID") %>'
                />

Method 2

I don’t know if it will really help you, but did you tried to setup the “SelectedValue” on Code behind?

Example:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    DropDownInfoSource.SelectedValue = "1" ' your value, here
End Sub

Method 3

There is a field where you define the datasource, the datatextfield (what shows up in the list) and the datavaluefield.

Example (I have a datatable with a column “EmployeeID” and a column “EmployeeName”):

dropdownlist1.datasource = DT
dropdownlist1.datatextfield = "EmployeeName"
dropdownlist1.datavaluefield = "EmployeeID"
dropdownlist1.databind()

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