How do I assign OnRowCommand to multiple IDs ASP.net and VB.net Backend - asp.net

Question

I have 2 GridViews with separate IDs
I need the backend code to update the one being viewed when a button is clicked.
` Protected Sub savestatus(sender As Object, e As EventArgs)
Dim btn As Button = TryCast(sender, Button)
Dim row As GridViewRow = CType(((CType(sender, Button)).NamingContainer), GridViewRow)
Dim rowindex As Integer = row.RowIndex
Dim code As String = GridView1.DataKeys(row.RowIndex).Values(0).ToString()
Dim type As Int32 = GridView1.DataKeys(row.RowIndex).Values(1)
Dim statusid As Integer
Dim checkLocked, checkerror As CheckBox
' For Each row As GridViewRow In GridView1.Rows
checkLocked = CType(GridView1.Rows(rowindex).FindControl("lock"), CheckBox)
checkerror = CType(GridView1.Rows(rowindex).FindControl("error"), CheckBox)
If checkerror.Checked Then ' error
statusid = 2
End If
If checkLocked.Checked Then
statusid = 3
End If`
How do I make the GridView1 a variable depending on which grid view the button is pressed in.

Answer 1

Ok, it would have helped a lot to at least show the button and a few rows of the gridview markup.
There are about 10 ways to do this. (really !!!).
However, in your case, two check boxes, and you need actions to occur when a check box is changed – AND say change the other one!!
Now I am using two check boxes – but it could be a text box or whatever I change.
So, say I have this grid markup
Some columns + TWO un-bound check boxes.
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false">
<Columns>
<asp:BoundField DataField="ID" HeaderText="ID" />
<asp:BoundField DataField="HotelName" HeaderText="HotelName" />
<asp:BoundField DataField="City" HeaderText="City" />
<asp:BoundField DataField="Province" HeaderText="Province" />
<asp:TemplateField HeaderText="Good">
<ItemTemplate>
<asp:CheckBox ID="chkGood" runat="server"
AutoPostBack="true"
OnCheckedChanged="chkGood_CheckedChanged"
MyRowID ='<%# Container.DataItemIndex %>' />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Bad">
<ItemTemplate>
<asp:CheckBox ID="chkBad" runat="server"
AutoPostBack="true"
OnCheckedChanged="chkBad_CheckedChanged"
MyRowID ='<%# Container.DataItemIndex %>' />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
Ok, and now the code to load the grid:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If IsPostBack = False Then
Using cmdSQL As New SqlCommand("SELECT ID, HotelName, City, Province from tblHotels",
New SqlConnection(My.Settings.Test3))
cmdSQL.Connection.Open()
GridView1.DataSource = cmdSQL.ExecuteReader
GridView1.DataBind()
End Using
End If
End Sub
And thus we have this:
Ok, so far - very simple.
Now note CLOSE at the markup for the two check boxes.
And while dropping a button or whatever on a normal form - you can then double click to JUMP to the code behind event/stub?
Well, for buttons or whatever you drop INSIDE of a grid, you can't double click on the control to create + jump to the code behind stub.
But, WHILE in the markup, you can start typing the event, and you get this:
Note VERY careful how the intel-sense pops up a option to create the event. So click on that option. Nothing seems to happen, but NOW we get a code stub behind.
So, we have this code stub for the chkOk event:
Protected Sub chkGood_CheckedChanged(sender As Object, e As EventArgs)
Dim ckBox As CheckBox = sender
Dim RowID As Integer = ckBox.Attributes.Item("MyRowID")
Dim gvRow As GridViewRow = GridView1.Rows(RowID)
If ckBox.Checked = True Then
' do whatever if true - say un-check the "bad" check box
Dim ckBoxBad As CheckBox = gvRow.FindControl("chkBad")
ckBoxBad.Checked = False
Else
' code here if the user just un-checked the "good" check box
End If
End Sub
Note a few things:
We pick up the button click - then shove it into a checkbox control. This is just a lot easier to get the check box value, and our CUSTOM MyRowID
(and this works if it was a button for example).
We then get the custom made up Attribute we added called "MyRowID"
MyRowID ='<%# Container.DataItemIndex %>'
You can see the expression in the Markup - it passes the current row id. Sometimes, I'll pass other values from the row and you can do this like this:
<asp:CheckBox ID="chkBad" runat="server"
AutoPostBack="true"
OnCheckedChanged="chkBad_CheckedChanged"
MyRowID ='<%# Container.DataItemIndex %>'
MyPKID = '<%# Eval("ID") %>' />
So in above, I pass both RowID and a custom MyPKID (so the Eval() expression can be used to pass any valid data row avaialble at binding time. Its often handy then having to grab and mess with a data row - you JUST grab the button from sender - and you don't care about gridview or anything else to get a few extra values. (just a FYI tip). So for example, I REALLY don't want the PK row id as the first row. So I could remove it and STILL use the above idea to PASS the pk row id - all columns can be used - even if a control is NOT in the grid - as long as the column exists during the data binding process - you can grab it.
So, now we pick up the current GridRow - and we are free to modify whatever we want on that row.
In my simple example, we pick up the OTHER check box - and un-check if it was checked. But we could say update other things on that row.
And I did the same for the chkBad check box. And I have really the same as the first chkBox code stub. Eg this:
Protected Sub chkBad_CheckedChanged(sender As Object, e As EventArgs)
Dim ckBox As CheckBox = sender
Dim RowID As Integer = ckBox.Attributes.Item("MyRowID")
Dim gvRow As GridViewRow = GridView1.Rows(RowID)
If ckBox.Checked = True Then
' user checked the bad box, un-check the good one
Dim ckBoxGood As CheckBox = gvRow.FindControl("chkGood")
ckBoxGood.Checked = False
Else
' code here if the user just un-checked the "bad" check box
End If
End Sub
So in above we just hard right past the GridView bult in events.
So in above, if you check one box and the other is checked - we un-check it. Needless to say, I would use a button list, or a checkbox list, and that above code would of course then not be required. But it still a good example on how to pluck/get the current row. And then get/pluck controls from that row.
Note that for the first 3 rows (the databound), you can NOT use findControl, and they are referenced using the gvRow.Cells(0) (starting at 0 to N columns. So no findcontrol is required for these databound columns or autogenerated ones. They do NOT have a name - you have to use number starting at 0 in the cells collection. Of course for "templated" controls that we added as per above? Then you do in fact use findcontrol as per above.