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What type of column to use?

Hi,

I have a datagrid with data columns "Date" and "status" for a particular document. I'd like to include a third button column called "reserve". I want this column to show up only if the status for the document is set to "Available". When the user clicks the button in a row, I don't want the datagrid to become editable. Instead all it should do is update the database and set the status for that particular row to "Checked out" and refresh the datagrid.

My problem is that I am not sure what kind of column i should use for this. A template column or a button column? Also how can I do the above using this column?

Thanks,
Aruna

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netcool

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arunatata

ASKER

Hi Netcool,

My datagrid has autogenerated columns and I added a button column in addition to those. The datagrid thus now has 3 columns

ButtonCol Date Status
Reserve 4/17/05 Available
Reserve 4/18/05 Available
4/19/05 Unavailable

The code for the datagrid itself is a whole different story. I created a datatable, flipped the columns and then bound them to the datagrid. I then programatically added the buttoncolumn using the following code:

Dim BtnCol As New ButtonColumn
With BtnCol
.Text = "Reserve "
.CommandName = "DG_Update(" & DocName & "," & ReservedDate & ")"
.HeaderText = "Action"
End With
DG.Columns.Add(BtnCol)
DG.DataBind()

All the above code created the datagrid shown above. As you can see, the commandname for the ButtonColumn has two parameters - DocName and ReservedDate.

Now whenever someone clicks on "Reserve" in the datagrid, I want it to go ahead and update the database with the status for that date set to "Unavailable". It should then update the datagrid with the fresh data.

My problem here is I don't know how to get the parameters from this code to the other sub "DG_Update" where the update function is being called. The itemcommand event needs DocName and ReservedDate as inputs. How do I pass these to it? And is the method I am following above correct?

Thanks,
A.

arunatata

ASKER

Actually moved a little further on this - I used viewstate to store the values of DocName and ReservedDate and am calling them from the same when the itemcommand event fires. However the itemcommand event is NOT firing. Please help!!

The structure of the page is as below:

It has two listboxes and a button. The button_click event take the values of the listboxes and uses them to query the database and print out a datagrid.

Sub Page_load
If Not Page.IsPostBack Then
'Bind data from a table to the listbox
Dim mainConnString As String = "Data Source=biginfo;Initial Catalog=aruna;User ID=sa"
Dim myConn As New SqlConnection(mainConnString)
Dim QueryString As String = "SELECT DocName FROM DocReserveDetail a INNER JOIN DocDetail b ON a.DocID = b.DocID"
Dim myCmd As New SqlCommand(QueryString, myConn)
myConn.Open()
Dim myDR As SqlDataReader
myDR = myCmd.ExecuteReader
ListDocs.DataSource = myDR
ListDocs.DataTextField = "DocName"

ListDocs.DataBind()

myDR.Close()
myConn.Close()
End If
End sub

Sub button_click
if page.ispostback then
'get values for DocName and Date
'Get dataset from getDataset() and bind to the datagrid
'add buttoncolumn to the datagrid
Dim myDV As DataView = getDataset(DocName, newDate).Tables(0).DefaultView

DG.DataSource = myDV
Dim BtnCol As New ButtonColumn
With BtnCol
.Text = "Reserve "
.CommandName = "DG_Update"
.HeaderText = "Action"
End With
DG.Columns.Add(BtnCol)
DG.Attributes.Add("OnitemCommand", "DG_Update")

DG.DataBind()
ViewState("DocName") = DocName
ViewState("newDate") = newDate
end if
end sub

Sub getDataset()
'Get values from database and bind
end sub

Sub DG_Update(byval sender as object, byval e as datagridcommandeventargs) handles dg.itemcommand
'THIS SUB IS NOT FIRING

Dim testername as string = convert.tostring(Viewstate("Testername"))
Dim newDate as string = convert.tostring(ViewState("newDate"))
end sub