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My app correctly populates a DataGrid column with ComboBoxes, using the following XAML code:

<DataGridTemplateColumn Header="Thickness">
    <DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
            <ComboBox ItemsSource="{Binding SteelThickness, RelativeSource={RelativeSource AncestorType=Window}}" SelectedItem="{Binding BottomPlateThickness, UpdateSourceTrigger=PropertyChanged}" SelectionChanged="ComboBox_SelectionChanged" />
        </DataTemplate>
    </DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
I am trying to figure out an expression such as
ComboBox cmb = dataGrid[i].Column[11].ComboBox
which will retrieve one ComboBox at a time.
                You are not supposed to access DataTemplate controls like that, what are you trying to do? as there is most likely a better way to achive your goal
– sa_ddam213
                Nov 28, 2013 at 0:22
                I am trying to debug my code, and inspect to see whether the item chosen with the ComboBox is actually the SelectedItem.
– Travis Banger
                Nov 28, 2013 at 0:38
                sa_ddam213: Since you are clearly knowledgeable, could you please take a look at my bigger problem? URL: (stackoverflow.com/questions/20249889/…)
– Travis Banger
                Nov 28, 2013 at 0:40
                Note: The XAML code was taken from here: (social.technet.microsoft.com/wiki/contents/articles/…), Example No. 9. That demo works quite well.
– Travis Banger
                Nov 28, 2013 at 0:43
//This class will help to get Row, Column or Cell by indices. Though there might not be some proper check for null and indices Sorry for that.I will update it later.
    public static class DataGridExtension
    public static DataGridColumn GetColumnByIndices(this DataGrid dataGrid, int rowIndex, int columnIndex)
        ValidateParameters(dataGrid, rowIndex, columnIndex);
        var row = dataGrid.GetRowByIndex(rowIndex);
        if (row != null)
            return row.GetRowColumnByIndex(columnIndex);
        return null;
    public static DataGridCell GetCellByIndices(this DataGrid dataGrid, int rowIndex, int columnIndex)
        ValidateParameters(dataGrid, rowIndex, columnIndex);
        var row = dataGrid.GetRowByIndex(rowIndex);
        if (row != null)
            return row.GetRowCellByColumnIndex(columnIndex);
        return null;
    //TODO:Validate RowIndex
    public static DataGridRow GetRowByIndex(this DataGrid dataGrid, int rowIndex)
        if (dataGrid == null)
            return null;
        return (DataGridRow)dataGrid.ItemContainerGenerator
                                                       .ContainerFromIndex(rowIndex);    
    //TODO:Validate ColumnIndex
    public static DataGridColumn GetRowColumnByIndex(this DataGridRow row, int columnIndex)
        if (row != null)
            var cell=GetRowCellByColumnIndex(row, columnIndex);
            if(cell!=null)
                return cell.Column;
        return null;
    //TODO:Validate ColumnIndex
    public static DataGridCell GetRowCellByColumnIndex(this DataGridRow row, int columnIndex)
        if (row != null)
            DataGridCellsPresenter cellPresenter = row.GetVisualChild<DataGridCellsPresenter>();
            if (cellPresenter != null)
                return ((DataGridCell)cellPresenter.ItemContainerGenerator.ContainerFromIndex(columnIndex));
        return null;
    private static void ValidateParameters(DataGrid dataGrid,int rowIndex,int columnIndex)
        if (dataGrid == null)
            throw new ArgumentNullException("datagrid is null");
        if (rowIndex >= dataGrid.Items.Count)
            throw new IndexOutOfRangeException("rowIndex out of Index");
        if (columnIndex >= dataGrid.Columns.Count)
            throw new IndexOutOfRangeException("columnIndex out of Index");
****//This Class will help to find the VisualChild ****
public static class VisualHelper
    public static T GetVisualChild<T>(this Visual parent) where T : Visual
        T child = default(T);
        for (int index = 0; index < VisualTreeHelper.GetChildrenCount(parent); index++)
            Visual visualChild = (Visual)VisualTreeHelper.GetChild(parent, index);
            child = visualChild as T;
            if (child == null)
                child = GetVisualChild<T>(visualChild);//Find Recursively
            if (child != null)
                break;
        return child;
Now you can use these classes to get Columns,Cells,Rows by Index like
        private void Button_Click_1(object sender, RoutedEventArgs e)
        //Now we can get Column like this.
        var column = dataGrid.GetColumnByIndices(1, 1);
        //As SO want to find the ComboBox within that Column 
        ComboBox comboBox;
        var cell = dataGrid.GetCellByIndices(1, 1); //DataGridColumn Does'nt Inherit Visual class so using GetCellByIndices
        if(cell!=null)
            comboBox = cell.GetVisualChild<ComboBox>(); //DataGridCell Inherit Visual so we can use our VisualHelper Method
        
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