public void UpdateFieldValueInItem_Invoke_SetsItem()
        {
            // Arrange
            _dropDownList                = new DropDownList();
            _dropDownList.DataSource     = _privateObject.GetFieldOrProperty(PropertyDataSource);
            _dropDownList.DataValueField = "ValueField";
            _dropDownList.DataTextField  = "TextField";
            _dropDownList.DataBind();
            _dropDownList.SelectedIndex = 0;
            _privateObject.SetFieldOrProperty(FieldDropList, _dropDownList);
            _privateObject.SetFieldOrProperty(FieldSelectedValueIndex, 0);

            // Act
            _testObject.UpdateFieldValueInItem();

            // Assert
            _item.ShouldNotBeNull();
        }