DropDownList inside Grid - asp.net

Question

I am using ASP.NET, I have a dropdownlist inside of a grid (radGrid).
What I like to happen is that when the dropdownlist appears, I like it to default to
"Please Select" only if the field that it is binding to is blank. Else, I like to to get the value from the DataSource.
I have the following code:
<asp:DropDownList ID="ddlEroGroup" runat="server" DataSourceID="EroGroupSource" DataTextField="Value" DataValueField="Value" AppendDataBoundItems="true" OnDataBound=" erogroupDropDown_DataBound" Text='<%# Bind("EroGroup") %>'>
</asp:DropDownList>
For the DataSource here is the code:
<asp:SqlDataSource ID="EroGroupSource" runat="server" ConnectionString="<%$ ConnectionStrings:ISQL %>"
SelectCommand="Select Value from LookupValues where Category = 'EroGroup'">
</asp:SqlDataSource>
Here is the code in the code-behind:
protected void ErogroupDropDown_DataBound(object sender, EventArgs e)
{
DropDownList list = sender as DropDownList;
if (list != null)
{
list.Items.Insert(0, new ListItem("Please Select", ""));
}
}
When it does the Binding, if the value is blank, I get an error saying that it could not find the value.

Answer 1

try:
protected void ErogroupDropDown_DataBound(object sender, EventArgs e)
{
DropDownList list = sender as DropDownList;
if (list.Items.Count.equals(0))
{
list.Items.Insert(0, new ListItem("Please Select", ""));
}
}

Answer 2

Use Grid PreRender event for this. May you would need to assign the value to some hidden label and access it inside prerender method and assign it to the dropdown.
<ItemTemplate>
<asp:Label runat="server" ID="lblValue" Text='<%# Eval("YourValue")%>' Visible="false" />
<asp:DropDownList ID="ddlEroGroup" runat="server" DataSourceID="EroGroupSource" DataTextField="Value" DataValueField="Value" AppendDataBoundItems="true" OnDataBound=" erogroupDropDown_DataBound" Text='<%# Bind("EroGroup") %>'>
</asp:DropDownList>
<asp:SqlDataSource ID="EroGroupSource" runat="server" ConnectionString="<%$ ConnectionStrings:ISQL %>"
SelectCommand="Select Value from LookupValues where Category = 'EroGroup'">
</asp:SqlDataSource>
</ItemTemplate>
On code behind:
protected void GridView1_PreRender(object sender, EventArgs e)
{
for(int i=0;i<Gridview1.Rows.Count;i++)
{
Label lblValue = (Label)Gridview1.Row[i].FindControl('lblValue');
DropdownList ddl = (DropdownList) Gridview1.Row[i].FindControl('ddlEroGroup');
ddl.Items.Insert(0, new ListItem("Please Select", ""));
if(lblValue!=null && !String.IsNullOrEmpty(lblValue.Text))
ddl.SelectedValue = lblValue.Text;
}
}