Adding Gridview Column of Checkboxes and Retrieving Values

nelper703 · April 24th, 2009, 04:48 PM

http://www.asp.net/learn/data-access...ial-52-vb.aspx

I am trying to use the tutorial provided but I am having trouble tweaking this for my application:

I need to be able to use checkboxes on a Gridview control to pull information from the first column of the Gridview and populate a Label control.

So basically I should be able to click multiple checkboxes, hit a button control and the data binded to each checkbox to column should appear where I can collect and do other things with.

My Gridview allows Editing and Sorting:

This is what i have so far in my ASPX page: (the Barcode field is the data i need to pull)

Code:

 
<asp:GridViewID="GridView1"runat="server"AllowPaging="True"
AllowSorting="True"AutoGenerateColumns="False"DataKeyNames="Barcode"DataSourceID="SqlDataSource1"Font-Size="Small"PageSize="20">
<Columns>
<asp:TemplateField>
<EditItemTemplate>
<asp:CheckBoxID="CheckBox1"runat="server"/>
</EditItemTemplate>
<ItemTemplate>
<asp:CheckBoxID="CheckBox1"runat="server"AutoPostBack="True"Checked='<%# Bind("Barcode") %>'/>
</ItemTemplate>
</asp:TemplateField>
<asp:CommandFieldShowEditButton="True"/>
<asp:BoundFieldDataField="Barcode"HeaderText="Barcode"ReadOnly="True"SortExpression="Barcode"/>
<asp:BoundFieldDataField="Media_Type"HeaderText="Media_Type"SortExpression="Media_Type"/>
<asp:BoundFieldDataField="Make"HeaderText="Make"SortExpression="Make"/>
<asp:BoundFieldDataField="Backup_Server"HeaderText="Backup_Server"SortExpression="Backup_Server"/>
<asp:BoundFieldDataField="Media_Set"HeaderText="Media_Set"SortExpression="Media_Set"/>
<asp:BoundFieldDataField="Backup_Date"HeaderText="Backup_Date"SortExpression="Backup_Date"/>
<asp:BoundFieldDataField="Location"HeaderText="Location"SortExpression="Location"/>
<asp:BoundFieldDataField="Archive"HeaderText="Archive"SortExpression="Archive"/>
<asp:BoundFieldDataField="Container"HeaderText="Container"SortExpression="Container"/>
<asp:BoundFieldDataField="Notes"HeaderText="Notes"SortExpression="Notes"/>
</Columns>
</asp:GridView>

Thanks for your help.

Lee Dumond · April 24th, 2009, 06:27 PM

It is not clear at all what you are trying to do here.

Is Barcode a Boolean value? Because that's the way you have it set up.

Also, you'd normally use Bind in the EditTemplate, and Eval in the ItemTemplate.

nelper703 · April 24th, 2009, 07:50 PM

Hi Lee,

Barcode is the name of my first column where I have data. This data is not boolean but is alphanumeric.

The checkbox is probably boolean as it can only be either checked, or unchecked.

I need to construct some VB code in my page behind which will do the following:

If the checkbox (or checkboxes) are checked then retrieve row value under the barcode column and paste these values to a label control.

I hope im making sense. I found some more info on how this can be done at: http://aspnetteam.wordpress.com/2008/10/20/dynamic-checkboxlist-control-nested-within-a-gridview-control/

Im going to try put some of this code together and let you know what I have.

Lee Dumond · April 24th, 2009, 08:44 PM

Quote:

Originally Posted by nelper703

Hi Lee,

Barcode is the name of my first column where I have data. This data is not boolean but is alphanumeric.

In that case, then what is this for?

Code:

<asp:CheckBoxID="CheckBox1"runat="server"AutoPostBack="True"Checked='<%# Bind("Barcode") %>'/>

The Checked property can only be true or false, so binding this to a non-Boolean value doesn't make sense.

nelper703 · April 25th, 2009, 05:48 PM

Thanks for pointing that out, I have just fixed that and also added the following VB to my code behind page:

This code basically sets up an array, then goes through each row checking if the checkbox is checked off.. If the checkbox is checked off then it pulls the value from the Barcode cell.

The array then prints to a textbox control labeled textbox1.

My problem is that only 1 value is getting printed out the textbox control and not all the rows that I have selected by checking off the checkbox...

What am I missing here?

Code:

 
Dim arr AsNew ArrayList()
For i AsInteger = 0 To GridView1.Rows.Count - 1
Dim cb As CheckBox = DirectCast(GridView1.Rows(i).Cells(0).FindControl("CheckBox1"), CheckBox)
If cb IsNotNothingThen
If cb.Checked Then
'get the value of BarCode here
Dim barCode AsString = GridView1.Rows(i).Cells(2).Text
' contains the column for BarCode
'add the value to ArrayList
arr.Add(barCode)
'TextBox1.Text = barCode.ToString()
Dim j AsInteger
For j = 0 To arr.Count - 1
Console.WriteLine(CStr(arr.Item(j)))
Dim output AsString
output = (CStr(arr.Item(j)))
TextBox1.Text = output
 
Next
 
EndIf
EndIf
 
Next
 
EndSub

Thanks for your help guys!

nelper703 · April 26th, 2009, 09:44 PM

Solution Found!

After researching some more I found a great example which I was able to easily modify to serve my purpose: http://vijaymodi.wordpress.com/2007/...-using-aspnet/

Here is the code I used, tested and working for reference:

Code:

 
ProtectedSub SelectedBarcodes_Click(ByVal sender AsObject, ByVal e As System.EventArgs) Handles SelectedBarcodes.Click
If IsPostBack = TrueThen
Dim str As StringBuilder = New StringBuilder()
' Select the checkboxes from the GridView control
Dim i AsInteger
For i = 0 To GridView1.Rows.Count - 1 Step i + 1
Dim row As GridViewRow = GridView1.Rows(i)
Dim isChecked AsBoolean = (CType(row.FindControl("CheckBox1"), CheckBox)).Checked
If (isChecked) Then
str.Append(GridView1.Rows(i).Cells(2).Text & ",")
EndIf
Next
' prints out the result
TextBox1.Text = (str.ToString())
EndIf
EndSub

Thank you all for your help.