Question

I have a WPF program that produces several DataGrids. I have added capability to export each grid to Excel using the ideas at this site:
http://www.codeproject.com/Articles/120480/Export-to-Excel-Functionality-in-WPF-DataGrid

Currently I just have a button under each grid that has its own handler that looks something like this:

private void m_btnExportTimePartitionToExcel_Click(object sender, RoutedEventArgs e)
    {
        try
        {
            ExportToExcel<SystemTimeRecordData, List<SystemTimeRecordData>> s = new ExportToExcel<SystemTimeRecordData, List<SystemTimeRecordData>>();
            ICollectionView view = CollectionViewSource.GetDefaultView(m_gridPartitionSystemTimeRecords.ItemsSource);
            s.dataToPrint = (List<SystemTimeRecordData>)view.SourceCollection;
            s.GenerateReport();
        }
        catch (Exception ex)
        {
            MessageBox.Show("Problem with exporting Excel. Error: " + ex.Message);
        }
    }

I have a similar button handler for each grid. This all works, but it “smells”. It seems there should be a way to have just one handler that each button calls. That is, if I can pass the grid associated with that button, and the relevant class. Can I do that from XAML? I have searched and seen examples of passing arguments, but not the grid itself and certainly not the class, which I’m guessing would have to be passed as a Type?
It would be nice to replace the above code with something like…

private void m_btnExportTimePartitionToExcel_Click(object sender, RoutedEventArgs e)
    {
        try
        {
                                    // some how get Type type, and grid from sender and/or e
            ExportToExcel<type, List<type>> s = new ExportToExcel<type, List<type>>();
            ICollectionView view = CollectionViewSource.GetDefaultView(m_grid.ItemsSource);
            s.dataToPrint = (List<type>)view.SourceCollection;
            s.GenerateReport();
        }
        catch (Exception ex)
        {
            MessageBox.Show("Problem with exporting Excel. Error: " + ex.Message);
        }
    }

Then I could just have one button handler! Any ideas?
Thanks,
Dave

Answer 1

Here are a few ways you could do that:

• You could try passing the DataGrid as the CommandParameter if you can find it using an ElementName or RelativeSource binding

  <Button CommandParameter="{Binding ElementName=DataGridA}" ... />
  
  <!-- Will only work if this is inside the DataGrid somewhere, like in the footer -->
  <Button CommandParameter="{Binding RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}" ... />
  

  You could then get the value with ((Button)sender).CommandParameter as DataGrid

• You could pass the ItemsSource as a CommandParameter instead of the entire DataGrid

  <StackPanel>
      <DataGrid ItemsSource="{Binding SomeCollection}" ... />
      <Button CommandParameter="{Binding SomeCollection}" ... />
  </StackPanel>
  

• You could navigate the VisualTree to find the closest DataGrid. I have some helpers on my blog that make this easy. Here’s an example using them with the above XAML:

  var parentPanel = VisualTreeHelpers.FindAncestor<StackPanel>((Button)sender);
  var datagrid = VisualTreeHelpers.FindChild<DataGrid>(parentPanel);
  

I’m sure there’s other ways too, but those are the first ones I thought of 🙂