WPF

[TemplatePart(Name = ComboBoxControl.INPUTCOMBOBOX_NAME, Type = typeof(ComboBox))]
    public class ComboBoxControl : Control
    {
        #region Constants
        const String CATEGORY_NAME = "Custom ComboBox Control";
        const String INPUTCOMBOBOX_NAME = "PART_InputComboBox";
        #endregion

        #region Properties
        ComboBox _inputComboBox;
        #endregion

        #region Dependency Properties
        public static readonly DependencyProperty DisplayMemberPathProperty =
            DependencyProperty.Register("DisplayMemberPath", typeof(string), typeof(ComboBoxControl), new UIPropertyMetadata(String.Empty));

        public static readonly DependencyProperty ItemsSourceProperty =
            DependencyProperty.Register("ItemsSource", typeof(IEnumerable), typeof(ComboBoxControl), new UIPropertyMetadata());

        // Other properties omitted
        #endregion

        #region Dependency Public Properties
        public string DisplayMemberPath
        {
            get { return (string)GetValue(DisplayMemberPathProperty); }
            set { SetValue(DisplayMemberPathProperty, value); }
        }

        public object ItemsSource
        {
            get { return (System.Collections.IEnumerable)GetValue(ItemsSourceProperty); }
            set { SetValue(ItemsSourceProperty, value); }
        }

        // Other properties omitted        
        #endregion

        #region Constructor
        public ComboBoxControl() { }

        static ComboBoxControl()
        {
            DefaultStyleKeyProperty.OverrideMetadata(typeof(ComboBoxControl), new FrameworkPropertyMetadata(typeof(ComboBoxControl)));
        }
        #endregion

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();

            _inputComboBox = (ComboBox)GetTemplateChild(INPUTCOMBOBOX_NAME);
        }
}

<Style TargetType="{x:Type local:ComboBoxControl}">
        <Setter Property="Label" Value=""/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type local:ComboBoxControl}">
                    <Border>
                        <DockPanel>

                            <!-- COMBO BOX  -->
                            <ComboBox x:Name="PART_InputComboBox" VerticalAlignment="Stretch" MinHeight="30"
                                      DisplayMemberPath="{TemplateBinding DisplayMemberPath}" 
                                      ItemsSource="{Binding Path=ItemsSource, Mode=TwoWay, RelativeSource={RelativeSource Mode=FindAncestor, 
                                AncestorType={x:Type local:ComboBoxControl}}, UpdateSourceTrigger=PropertyChanged}"/>
                        </DockPanel>
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

<ctl:ComboBoxControl ItemsSource="{Binding Path=Users, Mode=TwoWay}"/>

 private void btnValidate_Click(object sender, RoutedEventArgs e)
        { 
for (int j = 0; j < i - 1; j++)
            {
                TextBlock x = dgrecep.Columns[0].GetCellContent(dgrecep.Items[j]) as TextBlock;// GRID1 TABITEM1
                if (x != null)
                {
                    if (v.validate(x.Text))
                    {
                       
                       dgrecep2.Items.Add(dgrecep.Columns[0].GetCellContent(dgrecep.Items[j]));//GRID2 TABITEM2
                    }
                    else
                    {
                        MessageBox.Show("non valide");
                    }