DropDownList with GridView

Using a DropDownList to trigger a load in a GridView is such a great feature its a shame I had to go to a beta version book to find it.

Goal: 1 DropDownList of States filtering 1 GridView of Customers



1.) Add a DataSource control to handle data ( I chose SQL Server ):


<asp:SqlDataSource ID="SqlDataSource1" runat="server"
ConnectionString="<%$ ConnectionStrings:CustomersConnectionString %>"
SelectCommand="SELECT DISTINC State FROM [Customers] ORDERBY State"
EnableCaching="True" CacheDuration="300" />



Note : The connection string is from my web.config
Note : Cache because the data doesnt usually change [Just a group of States]




2.) Add a DropDownList control let's say full of States:

<asp:dropdownlist id="statesDDL" DataSourceID="SqlDataSource1"
DataTextField="State" AutoPostBack="True" runat="server" />

Note: AutoPostBack="True" to trigger the post back on change




3.) Add a Second DataSource Control with cool attributes:



<asp:sqldatasource id="SqlDataSource2"  connectionstring="<%$
"ConnectionStrings:CustomersConnectionString %
>"
SelectCommand="SELECT CustName,CustAddress,CustCity,CustPhone FROM [Customers]
WHERE State=@State">


<SelectParameters>
<asp:ControlParameter Name="State" ControlID="statesDDL" PropertyName="SelectedValue" />
</SelectParameters>

</asp:SqlDataSource>



4.) Add a GridView which will have data filtered by State:

<asp:GridView id="grid1" DataSourceID="SqlDataSource2" runat="server" />

( Dont ya just love the gridView code. )