追加新行时移位的datagrid行选择

Question

标题##一个非常简单的演示，用以说明困扰我的地方：

我的XAML：

<Window x:Class="DataGridSelectionDemo.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
        Title="DataGrid selection demo" Height="350" Width="525">
        <Grid>
            <DataGrid x:Name="dataGridEmp" CellEditEnding="OnDataGridCellEditEnding"
                    AutoGenerateColumns="False"
                    DockPanel.Dock="Top"
                    ItemsSource="{Binding}">
                <DataGrid.Columns>
                    <DataGridTextColumn x:Name="Code" Header="Code" Width="60" Binding="{Binding Path=Code, Mode=TwoWay}" />
                    <DataGridTextColumn x:Name="Name" Header="Name" Width="200" Binding="{Binding Path=Name, Mode=TwoWay}" />
                </DataGrid.Columns>
            </DataGrid>
        </Grid>
</Window>

我的代码后面：

    {
        public class Employee
        {
            public string Code { get; set; }
            public string Name { get; set; }
        }
        private ObservableCollection<Employee> EmpCollection = 
            new ObservableCollection<Employee>
            {
                new Employee {Code = "E004", Name = "George"},
                new Employee {Code = "E005", Name = "Jason"},
                new Employee {Code = "E006", Name = "Robert"},
                new Employee {Code = "E007", Name = "Roger"},
                new Employee {Code = "E008", Name = "Patrick"},
                new Employee {Code = "E009", Name = "Preston"},
                new Employee {Code = "E010", Name = "Theodor"},
                new Employee {Code = "E011", Name = "Thomas"},
                new Employee {Code = "E012", Name = "Trenton"},
                new Employee {Code = "E013", Name = "Abel"},
                new Employee {Code = "E014", Name = "Cedrick"},
                new Employee {Code = "E015", Name = "Celine"},
                new Employee {Code = "E016", Name = "David"},
                new Employee {Code = "E017", Name = "Donald"},
                new Employee {Code = "E018", Name = "Everett"},
                new Employee {Code = "E019", Name = "Fred"},
                new Employee {Code = "E020", Name = "Harold"},
                new Employee {Code = "E021", Name = "Khalid"},
                new Employee {Code = "E022", Name = "Lionel"},
                new Employee {Code = "E023", Name = "Manuel"}
            };
        public MainWindow()
        {
            InitializeComponent();
            dataGridEmp.ItemsSource = EmpCollection;
        }
         private void OnDataGridCellEditEnding(object sender, DataGridCellEditEndingEventArgs e)
        {

            DataGridRow currentRow = e.Row;
            int currentRow_index = ((DataGrid)sender).ItemContainerGenerator.IndexFromContainer(currentRow);
            if (currentRow.Item as Employee == null) return;
            string searchedText = (e.EditingElement as TextBox).Text;
            for (int i = 0; i < dataGridEmp.Items.Count; i++)
            {
                if (i == currentRow_index) continue;
                dataGridEmp.ScrollIntoView(dataGridEmp.Items[i]);
                DataGridRow row = (DataGridRow)dataGridEmp.ItemContainerGenerator.ContainerFromIndex(i);
                if (row.Item as Employee == null) break;
                string cellContent = (row.Item as Employee).Name;
                if (cellContent != null && cellContent.Equals(searchedText))
                {
                    object item = dataGridEmp.Items[i];
                    dataGridEmp.SelectedItem = item;
                    dataGridEmp.ScrollIntoView(item);
                    row.MoveFocus(new TraversalRequest(FocusNavigationDirection.Next));
                    break;
                }
            }
        }
    }

我要防止输入重复的名称。当我输入新名称时，一切都按预期进行。但是，当我在数据网格中输入一个名称时，就会发生一些奇怪的事情：如果在视图中已经存在现有名称，则根据需要选择正确的行，但是如果不在视图中，则选择下一行。尝试输入第一个“ Fred”和下一个“ George”。

当我进行调试时，还会看到另一个非常令人困惑的事情（我无法粘贴图像，因此我将进行描述）。在行上设置断点

row.MoveFocus（new TraversalRequest（FocusNavigationDirection.Next））;

，然后输入一个重复的名称（“乔治”）。调试器在那里停止，但是如果您尝试使用F10，它就不会进入“中断”状态。 （下一行），但停留在断点上。仅在第二个F10上，它才继续执行“ break;”。很奇怪！

很明显，插入行将使信息在视图中向上移动，而选择将移至下一行。但是为什么以及如何避免呢？接下来，当输入重复的名称时，如何删除附加的行，然后将焦点移至现有名称？