How do I write code to select/unselect all checkbox on selecting checkbox header of data grid WPF?

This question may seem very old but I am not able to solve myself.

I am new to WPF.

I am facing little issues on working with data grid in WPF. Previously I was comfortable with Windows forms.

I have added a checkbox column in data grid and added a checkbox in the header.

Now How do I write code to select/unselect all checkbox on selecting checkbox header?

I tried all the possible answers from other posts but I am unable to success on it. I am little confused somewhere.

<DataGrid AutoGenerateColumns="True" Height="204" HorizontalAlignment="Left" Margin="38,162,0,48" Name="dataGrid1" VerticalAlignment="Stretch" Width="729" AreRowDetailsFrozen="False"  EnableColumnVirtualization="False" IsManipulationEnabled="False" CanUserAddRows="False" AutoGeneratingColumn="dataGrid1_AutoGeneratingColumn" RowHeight="26" ColumnHeaderHeight="26" FontSize="15">
                    <DataGrid.Columns>
                        <DataGridCheckBoxColumn >
                            <DataGridCheckBoxColumn.Header>
                                <CheckBox Name="SelectAll" ></CheckBox>
                            </DataGridCheckBoxColumn.Header>
                        </DataGridCheckBoxColumn>
                    </DataGrid.Columns>
</DataGrid>

What should I do next?