RadGrid read GridTemplateColumn

[Sue]

I have a grid with items that are only read in code, both on client and server side and not all of them are editable by the user.

Here is part of grid setup

 

<telerik:RadGrid ID="RadGridM" runat="server" DataSourceID="DatabaseItem" OnPageIndexChanged="PageChange"

 

 

AutoGenerateColumns="False" GridLines="None" AllowMultiRowSelection="true" EnableViewState="false"

 

 

Skin="Office2007" AllowPaging="True" PageSize="25"

 

 

AllowFilteringByColumn="True" OnPreRender="RadGridM_PreRender" >

 

 

<Columns>

 

<telerik:GridTemplateColumn DataField="QtyOrd"

 

 

HeaderText="Qty Ord" ReadOnly="False" SortExpression="QtyOrd" UniqueName="QtyOrd" Visible="true" AllowFiltering="false" >

 

 

<ItemTemplate>

 

 

<asp:TextBox ID="txtQtyOrdI" runat="server" Text='<%# Bind( "QtyOrd") %>'

 

 

Visible="true"></asp:TextBox>

 

<%

# DataBinder.Eval(Container.DataItem, "QtyOrd")%>

 

 

</ItemTemplate>

 

 

<EditItemTemplate>

 

 

<asp:TextBox ID="txtQtyOrd" runat="server" Text='<%# Bind( "QtyOrd") %>' Width="10pt"></asp:TextBox>
<asp:TableCell><asp:CustomValidator ID="Validate_Qty" runat="server" ControlToValidate="txtQtyOrd" ErrorMessage="Amount must be greater than 0." OnServerValidate="CustomValidator_Qty"></asp:CustomValidator>

 

 

</EditItemTemplate>

 

 

</telerik:GridTemplateColumn >

 

 

<telerik:GridBoundColumn DataField="ItemNumber" HeaderText="Item Number" ReadOnly="True" SortExpression="ItemNumber" UniqueName="ItemNumber" Visible="true">

 

 

 

 

 

</telerik:GridBoundColumn>

 

 

 

 

 

</Columns>

 

 

</mastertableview>

 

 

 

 

 

</telerik:RadGrid>

 

 

<asp:Button ID="Selection" runat="server" Text="Add Selected" onclick="Selection_Click" />

 

 

 

On the server side when the user presses the Selection button I need to read all the values of each line on the RadGrid.
I am able to get the items with a GridTemplateColumn using this code

 

 

foreach (GridDataItem item1 in RadGridM.Items)

 

{

 

 

GridDataItem item = (GridDataItem)item1;

 

 

TextBox QtyVal = item.FindControl("txtQtyOrdI") as TextBox;

 

 

}

This does not work for the GridTemplateColumn, ItemNumber

I have tried getting the DataRowView, and adding the Item Template to the GridTemplateColumn, but the value or item comes back null.

I have also tried item["ItemNumber"] and item["ItemNumber"].Control[0] 

If I have a grid that does not allow any editing, but diplays values I need to process server side, and all items are in the form, below, how to a loop through each row on the server side and read the text from every column?

 

 

<telerik:GridBoundColumn DataField="testvalue" HeaderText="testvalue"

 

 

SortExpression="testvalue" UniqueName="testvalue" Visible="true" ReadOnly="True">

 

 

</telerik:GridBoundColumn>

I have also tried the things in this post, and they only work on an Item Template.

 

 

http://www.telerik.com/community/forums/aspnet-ajax/grid/itemdatabound-on-gridtemplatecolumn.aspx

Thanks
Sue

 

 

 

 

[Princy]

Hello Sue,

Try the following approach to get the value in ItemTemplate of GridTemplateColumn.

C#:

protected void Selection_Click(object sender, EventArgs e)
   {
       foreach (GridDataItem item1 in RadGridM.Items)
       {
           GridDataItem item = (GridDataItem)item1;
           string QtyOrd = DataBinder.Eval(item.DataItem, "QtyOrd").ToString();// get the value in GridTemplateColumn
           string ItemNumber = item["ItemNumber"].Text; // get the value in GridBoundColumn 'ItemNumber'
       }

   }

Also please go through the following documentation which explains how to access the values in grid cells.
Accessing cells and rows

Thanks,
Princy.

[Sue]

Hi Princy,

I have already tried this method and every other one here Accessing cells and rows before posting.


Both the lines suggested below return and "Object not set to an instance of an object" error.

Can you provide working sample code that will read from a GridBoundColumn and GridTemplateColumn?

Thanks
Sue

[Princy]

Hello Sue,

The above code is working fine at my end. Another approach is you can use one Label inside ItemTemplate of GridTemplateColumn. Here is the sample code which shows how to loops through each grid item and access its BoundColumn and TemplateColumn's value on an external button click.

ASPX:


<telerik:RadGrid ID="RadGrid2" runat="server" DataSourceID="SqlDataSource1" AutoGenerateColumns="False">
<MasterTableView>
<Columns>
    <telerik:GridBoundColumn DataField="FirstName" HeaderText="FirstName" UniqueName="FirstName">
    </telerik:GridBoundColumn>
    <telerik:GridTemplateColumn>
        <ItemTemplate>
            <asp:Label ID="Label1" runat="server" Text='<%#Eval("FirstName") %>'></asp:Label>
        </ItemTemplate>
    </telerik:GridTemplateColumn>
</Columns>
</MasterTableView>
</telerik:RadGrid>

<br />
<asp:Button ID="Button1" runat="server" Text="Search" onclick="Button1_Click" />

C#:

protected void Button1_Click(object sender, EventArgs e)
   {
       foreach (GridDataItem item in RadGrid2.Items)
       {
           string BoundColumnValue = item["FirstName"].Text; // accessing GridBoundColumn value using ColumnUniqueName
           Label lb = (Label)item.FindControl("Label1");// accessing Label control inside ItemTemplate
           string TemplateColumnValue = lb.Text;// accessing Label Text.
       }
   }

Thanks,
Princy.

[Alan T]

the text property of my cell is returning an empty string, i'm not sure why

my markup is like

<ItemTemplate>
some html text including anchors, img etc. (Not server side controls)
</ItemTemplate>

and i'm doing

For Each item As GridDataItem In grid.MasterTableView.Items
    Dim cell As TableCell = TryCast(item("published"), TableCell)
    cell.Text  = ...
Next

cell.Text is empty, i don't understand why, because.. it's not.

[Alan T]

fixed my issue; this removes html img from the cell. (for exporting)

                    cell = TryCast(item("published"), TableCell)     
              For Each ctrl As DataBoundLiteralControl In cell.Controls
                        Dim strtIndex As Integer = ctrl.Text.IndexOf("<img")
                        If strtIndex > 0 Then
                            Dim endIndex As Integer = ctrl.Text.IndexOf("/>", strtIndex)

                            Dim substr As String = ctrl.Text.Substring(strtIndex, (endIndex - strtIndex) + 2)

                            cell.Text = ctrl.Text.Replace(substr, "")
                        End If
                    Next

[Alan T]

Thought i had fixed this but it appears not.

infact any changes i make to the Cell.Text property do not seem to appear in the exported file, why is this ?

For Each col As GridColumn In grid.MasterTableView.Columns
    If col.Visible Then
        Dim cell As TableCell = item(col.UniqueName)

        If cell.Controls.Count > 0 Then
            For Each ctrl As Control In item(col.UniqueName).Controls
                If TypeOf (ctrl) Is DataBoundLiteralControl Then
                    Dim strtIndex As Integer = TryCast(ctrl, DataBoundLiteralControl).Text.IndexOf("<img")
                    If strtIndex > 0 Then
                        Dim endIndex As Integer = TryCast(ctrl, DataBoundLiteralControl).Text.IndexOf("/>", strtIndex)

                        Dim substr As String = TryCast(ctrl, DataBoundLiteralControl).Text.Substring(strtIndex, (endIndex - strtIndex) + 2)

                        cell.Text &= TryCast(ctrl, DataBoundLiteralControl).Text.Replace(substr, "")

                        cell.Text = general_functions.RemoveHTML(cell.Text.Replace("\n", "<br />"))
                        cell.Text = cell.Text.Trim.Replace("<br />", " ").Replace("€", "€")
                        cell.Text &= cell.Text.Trim
                    End If
                End If
            Next
        Else
            Dim strtIndex As Integer = cell.Text.IndexOf("<img")
            If strtIndex > 0 Then
                Dim endIndex As Integer = cell.Text.IndexOf("/>", strtIndex)

                Dim substr As String = cell.Text.Substring(strtIndex, (endIndex - strtIndex) + 2)

                cell.Text &= cell.Text.Replace(substr, "")

            End If
        End If
    End If
Next

[Veli]

Hi Alan,

When you have a GridTemplateColumn, the cell that has your content rendered for this column does not have its Text property set. Instead, a LiteralControl is rendered in the Controls collection of the cell and this LiteralControl contains the text in your column's ItemTemplate. If you have server controls in the ItemTemplate, they also appear in the Controls collection of your cell. So, you need to find the appropriate control and get/set its value instead of attempting to read and set the cell.Text property.

Veli
the Telerik team

[Alan T]

Yeah i knew that, can you review my code above and see why it might not work ? I'm looping through the controls and building up the text property to set to the cell for when exported.

[Veli]

You may want to add the text you are building to a buffer string variable first, before setting the TableCell.Text property. This is because a table cell clears its controls collection if you set its text. Here is the TableCell.Text property implementation, as shown by Reflector:

[WebSysDescription("TableCell_Text"), DefaultValue(""), PersistenceMode(PersistenceMode.InnerDefaultProperty), Localizable(true), WebCategory("Appearance")]
public virtual string Text
{
    get
    {
        object obj2 = this.ViewState["Text"];
        if (obj2 != null)
        {
            return (string) obj2;
        }
        return string.Empty;
    }
    set
    {
        if (this.HasControls())
        {
            this.Controls.Clear();
        }
        this.ViewState["Text"] = value;
    }
}

Note how the setter clears the controls collection of the table cell if you try to set its text. This means your controls may be cleared before you loop through them all.

Veli
the Telerik team

[Alan T]

OK at a loss here. somehow my export is now completely blank, even though i can see whilst debugging that the cell's .Text property is being assigned.
here's all the code

For Each item As GridDataItem In rg_properties.MasterTableView.Items

     Dim datakey As DataKey = rg_properties.MasterTableView.DataKeyValues(item.ItemIndex)

     For Each col As GridColumn In rg_properties.MasterTableView.Columns
         If col.Visible Then
             Dim cell As TableCell = item(col.UniqueName)

             If cell.Controls.Count > 0 Then
                 Dim cellText As String = ""
                 For Each ctrl As Control In item(col.UniqueName).Controls
                     If TypeOf (ctrl) Is DataBoundLiteralControl Then
                         Dim strtIndex As Integer = TryCast(ctrl, DataBoundLiteralControl).Text.IndexOf("<img")
                         If strtIndex > 0 Then
                             Dim endIndex As Integer = TryCast(ctrl, DataBoundLiteralControl).Text.IndexOf("/>", strtIndex)

                             Dim substr As String = TryCast(ctrl, DataBoundLiteralControl).Text.Substring(strtIndex, (endIndex - strtIndex) + 2)

                             cellText &= TryCast(ctrl, DataBoundLiteralControl).Text.Replace(substr, "")
                         Else
                             cellText &= TryCast(ctrl, DataBoundLiteralControl).Text
                         End If

                     End If
                 Next

                 cellText = general_functions.RemoveHTML(cellText.Replace("\n", "<br />"))
                 cellText = cellText.Replace("<br />", " ").Replace("€", "€")
                 cellText = cellText.Trim
                 cell.Text = cellText
             Else
                 Dim strtIndex As Integer = cell.Text.IndexOf("<img")
                 If strtIndex > 0 Then
                     Dim endIndex As Integer = cell.Text.IndexOf("/>", strtIndex)

                     Dim substr As String = cell.Text.Substring(strtIndex, (endIndex - strtIndex) + 2)

                     cell.Text = cell.Text.Replace(substr, "")

                 End If
             End If
         End If
     Next
 Next

 If e.CommandName = Telerik.Web.UI.RadGrid.ExportToExcelCommandName Then
     rg_properties.MasterTableView.ExportToExcel()
End If

[Veli]

When exporting, RadGrid rebinds automatically. This means your items and controls inside will get recreated. To replace cell text when exporting, you need to use an alternative approach. You can use the ItemCommand event in RadGrid to only raise a flag that the grid is exporting. Then you can use the ItemDataBound event to do the actual cell text formatting:

Private exporting As Boolean = False
Protected Sub rg_properties_ItemCommand(ByVal sender As Object, ByVal e As GridCommandEventArgs) Handles rg_properties.ItemCommand
    If e.CommandName.ToString("ExportTo") Then
        exporting = True
    End If
End Sub

Protected Sub rg_properties_ItemDataBound(ByVal sender As Object, ByVal e As GridItemEventArgs) Handles rg_properties.ItemDataBound
    If (e.Item.ItemType = GridItemType.Item Or e.Item.ItemType = GridItemType.AlternatingItem) And exporting Then
        Dim item As GridDataItem = e.Item
        'replace cell text here
    End If
End Sub

Using the above approach, the cell text is replaced just at the right moment.

Veli
the Telerik team

[Alan T]

still not having any luck.

Private Sub rg_properties_ItemDataBound(ByVal sender As Object, ByVal e As Telerik.Web.UI.GridItemEventArgs) Handles rg_properties.ItemDataBound
        If (e.Item.ItemType = GridItemType.Item Or e.Item.ItemType = GridItemType.AlternatingItem) And exporting = True Then
            Dim item As GridDataItem = e.Item

            'replace cell text here
            For Each cell As TableCell In item.Cells
                If cell.Visible = True Then
                    If cell.Controls.Count > 0 Then
                        Dim cellText As String = ""
                        For Each ctrl As Control In cell.Controls
                            If TypeOf (ctrl) Is DataBoundLiteralControl Then
                                Dim strtIndex As Integer = TryCast(ctrl, DataBoundLiteralControl).Text.IndexOf("<img")

                                'is there an image tag?
                                If strtIndex > 0 Then
                                    Dim endIndex As Integer = TryCast(ctrl, DataBoundLiteralControl).Text.IndexOf("/>", strtIndex)

                                    Dim substr As String = TryCast(ctrl, DataBoundLiteralControl).Text.Substring(strtIndex, (endIndex - strtIndex) + 2)

                                    cellText &= TryCast(ctrl, DataBoundLiteralControl).Text.Replace(substr, "")
                                Else
                                    cellText &= TryCast(ctrl, DataBoundLiteralControl).Text
                                End If

                            End If
                        Next

                        cellText = general_functions.RemoveHTML(cellText.Replace("\n", "<br />"))
                        cellText = cellText.Replace("<br />", " ").Replace("€", "€")
                        cellText = cellText.Trim
                        cell.Text = cellText
                    Else
                        Dim strtIndex As Integer = cell.Text.IndexOf("<img")
                        'is there an image tag?
                        If strtIndex > 0 Then
                            Dim endIndex As Integer = cell.Text.IndexOf("/>", strtIndex)

                            Dim substr As String = cell.Text.Substring(strtIndex, (endIndex - strtIndex) + 2)

                            cell.Text = cell.Text.Replace(substr, "")
                        End If
                    End If
                End If
            Next
        End If
    End Sub

[Alan T]

hmm.. setting exportonlydata to false seems to result in some data being exported. although some of which i dont want.

[Veli]

If this issue persists, consider opening a regular support ticket where you can send us a stripped down runnable project we can debug locally. This will help us better understand your scenario and advise you further.

Veli
the Telerik team

[TripDev]

I have also been having this issue however Princy's second post worked for me.

Thank you.

[Carlos]

I'm having the same issue where the values are empty strings. but besides Princy's second post which also worded for me, I was able to get the value this way  TryCast(item("FirstName").Controls(0), textbox).text (VB).   

 (item("​FirstName").Controls(0) as textbox).text (C#)

[Eyup]

Hello Carlos,

Thank you for sharing your approach and experience with our community. I hope it may prove helpful to other developers as well.

Regards,
Eyup
Telerik