<DataGrid x:Name="DataGridRegisteredUsers" IsReadOnly="True" AutoGenerateColumns="False"
                                  HorizontalContentAlignment="Stretch" Margin="0,0,-1,-1"
                                  FlowDirection="RightToLeft" Opacity="0.9" FontFamily="B Nazanin" FontSize="15" RowDetailsVisibilityMode="Visible">
                            <DataGrid.Columns>
                                <DataGridTextColumn Binding="{Binding Path=UserID}" IsReadOnly="True"
                                                    Header="UserID" />
                                <DataGridTextColumn Binding="{Binding Path=FirstName}"
                                                    Header="First Name" />
                                <DataGridTextColumn Binding="{Binding Path=LastName}"
                                                    Header="Last Name" />
                                <DataGridTextColumn Binding="{Binding Path=EmploymentID}"
                                                    Header="Employment ID" />
                                <DataGridTextColumn Binding="{Binding Path=Status}"
                                                    Header="Status" />
                            </DataGrid.Columns>
                        </DataGrid>

foreach (var userID in DataGridSelectedUserIDs)
        {
            var findQ = (from f in dbEntities.RelCUs
                where f.UserID == userID && f.CourseID == currCourse.CourseID
                select f);
            foreach (var relCu in findQ)
            {
                dbEntities.RelCUs.Remove(relCu);
                dbEntities.SaveChanges();
            }
        }