cannot find Name of DataGridColumn programmatically - wpf

Question

I found the Columns collection in my datagrid, and was hoping to iterate through it to find a certain column Name. However, I can't figure out how to address the x:Name attribute of the column. This xaml illustrates my problem with a DataGridTextColumn and a DataGridTemplateColumn:
<t:DataGrid x:Name="dgEmployees" ItemsSource="{Binding Employees}"
AutoGenerateColumns="false" Height="300" >
<t:DataGrid.Columns>
<t:DataGridTextColumn x:Name="FirstName" Header="FirstName"
Binding="{Binding FirstName}" />
<t:DataGridTemplateColumn x:Name="LastName" Header="LastName" >
<t:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBlock Text="{Binding LastName}" />
</DataTemplate>
</t:DataGridTemplateColumn.CellTemplate>
</t:DataGridTemplateColumn>
</t:DataGrid.Columns>
</t:DataGrid>
And here is my code:
DataGrid dg = this.dgEmployees;
foreach (var column in dg.Columns)
{
System.Console.WriteLine("name: " + (string)column.GetValue(NameProperty));
}
At runtime, no value is present; column.GetValue doesn't return anything. Using Snoop, I confirmed that there is no Name property on either DataGridTextColumn or DataGridTemplateColumn.
What am I missing?

Answer 1

WPF has two different, yet similar concepts, x:Name, which is used to create a field which references an element defined in XAML, i.e. connecting your code-behind to your XAML, and FrameworkElement.Name, which uniquely names an element within a namescope.
If an element has a FrameworkElement.Name property, x:Name will set this property to the value given in XAML. However, there are instances where it is useful to link non FrameworkElement elements to fields in code-behind, such as in your example.
See this related question:
In WPF, what are the differences between the x:Name and Name attributes?
As an alternative, you could define your own attached property which can be used to name the columns. The attached property is defined as follows:
public class DataGridUtil
{
public static string GetName(DependencyObject obj)
{
return (string)obj.GetValue(NameProperty);
}
public static void SetName(DependencyObject obj, string value)
{
obj.SetValue(NameProperty, value);
}
public static readonly DependencyProperty NameProperty =
DependencyProperty.RegisterAttached("Name", typeof(string), typeof(DataGridUtil), new UIPropertyMetadata(""));
}
You can then assign a name to each column ...
xmlns:util="clr-namespace:WPFDataGridExamples"
<t:DataGrid x:Name="dgEmployees" ItemsSource="{Binding Employees}"
AutoGenerateColumns="false" Height="300" >
<t:DataGrid.Columns>
<t:DataGridTextColumn util:DataGridUtil.Name="FirstName" Header="FirstName"
Binding="{Binding FirstName}" />
<t:DataGridTemplateColumn util:DataGridUtil.Name="LastName" Header="LastName" >
<t:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBlock Text="{Binding LastName}" />
</DataTemplate>
</t:DataGridTemplateColumn.CellTemplate>
</t:DataGridTemplateColumn>
</t:DataGrid.Columns>
</t:DataGrid>
Then access this name in code as follows:
DataGrid dg = this.dgEmployees;
foreach (var column in dg.Columns)
{
System.Console.WriteLine("name: " + DataGridUtil.GetName(column));
}
Hope that helps

Answer 2

You can use linq query to find name of the datagrid column Headers
dgvReports.Columns.Select(a=>a.Header.ToString()).ToList()
where dgvReports is name of the datagrid.