gridview: show link, but edit a dropdownlist

I have a gridview, and it has an author column. I want to display the author name as a hyperlink, so when the user clicks on it he gets redirected to the author page. But when the user wishes to edit the author for current product, he should see a dropdownlist. I am trying to implement it using a template field:

<asp:TemplateField HeaderText="автор">
        <ItemTemplate>
            <asp:HyperLink ID="HyperLink1" runat="server" NavigateURL='<%# "~/CMS/AuthorPage.aspx?a="+ Eval("AuthorID")%>' Text='<%#Eval("AuthorID")%>' />      开发者_StackOverflow社区                              
        </ItemTemplate>
        <EditItemTemplate>
                <asp:DropDownList ID="DropDownList1" runat="server" DataSourceID="SqlDataSource3" 
        DataTextField="Name" DataValueField="ID"/>
<asp:SqlDataSource ID="SqlDataSource3" runat="server" 
        ConnectionString="<%$ ConnectionStrings:aspnetdbConnectionString1 %>" 
        SelectCommand="SELECT [ID], [Name] FROM [Authors] ORDER BY [Name]"></asp:SqlDataSource>                
</EditItemTemplate>
</asp:TemplateField>       

But how do I specify the selected value, and how do I store the selected value after edit?

You need to do it in RowDataBound event of GridView and then in RowUpdating event you can get the selected value

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
    DropDownList DropDownList1 = (DropDownList)e.Row.FindControl("DropDownList1");
    DropDownList1.SelectedValue = "SomeID";
}

and get the selected value by

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
    DropDownList DropDownList1 = (DropDownList)this.GridView1.Rows[e.RowIndex].FindControl("DropDownList1");
    string value = DropDownList1.SelectedValue;
}