problem with populating a dropdownlist in editTemplate of detailsview

[Jan]

Hi,

i defined a dropdownlist in an EditTemplate of a detailsview like this:

<EditItemTemplate>
<aspropDownList ID="drop1" runat="server"></aspropDownList>
</EditItemTemplate>

I want to populate it in code-behind; i tried this:

Protected Sub DetailsView1_ItemCreated(ByVal sender As Object, ByVal e As
System.EventArgs) Handles DetailsView1.ItemCreated
If DataControlRowState.Edit Then 'only in edit mode
If DataControlRowType.DataRow Then 'only datarow
Dim dd1 As DropDownList
Dim z1 As ListItem
Dim i As Integer
dd1 = CType(DetailsView1.Rows(5).FindControl("drop1"),
DropDownList)
For i = 0 To 20
z1 = New ListItem(i, i)
dd1.Items.Add(z1)
Next
End If
End If
End Sub

But i get the error:"Object reference not set to an instance of an object"
at line: dd1.Items.Add(z1)

Thanks for help
Jan

 

[Guest]

Jan,

Seems your dropdownlist is not plaved in the 5th row (remember in this case
rows are numbered starting from zero). Anyway, you don't have to use
row(index), just try DetailsView1.FindControl("drop1"). If this doesn't work,
try to debug this line of the code and find the control location (ie. by
traversing the control tree within the with Quick View window).

HTH

 

[Jan]

Ji Milosz, thanks for replying.

I tried DetailsView1.FindControl("drop1") but still same error ...
I use VWD (Visual web dev.) and i don't understand what you mean with:"try
to debug this line of the code and find the control location (ie. by
traversing the control tree within the with Quick View window)."

I get the error even in normal mode. Maybe are these lines not correct:
If DataControlRowState.Edit Then

If DataControlRowType.DataRow Then



......