wpf 按下箭头键时不会触发文本框 Keydown 事件
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Textbox Keydown event not firing when arrow key press
提问by Mussammil
I have a datagrid with one column as DataGridTemplateColumn as follows :
我有一个数据网格，其中一列作为 DataGridTemplateColumn 如下：
<my:DataGrid Name="dgvSales" RowHeight="23" SelectionUnit="Cell" BeginningEdit="dgvSales_BeginningEdit" AutoGenerateColumns="False" CellEditEnding="dgvSales_CellEditEnding" >
<my:DataGrid.Columns>
<my:DataGridTemplateColumn Header="Product Name" Width="200">
<my:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBlock Text="{Binding Product_Name}"></TextBlock>
</DataTemplate>
</my:DataGridTemplateColumn.CellTemplate>
<my:DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<TextBox x:Name="txtbxProduct" Text="{Binding Product_Name}" TextChanged="txtbxProduct_TextChanged" KeyDown="txtbxProduct_KeyDown"></TextBox>
</DataTemplate>
</my:DataGridTemplateColumn.CellEditingTemplate>
</my:DataGridTemplateColumn>
</my:DataGrid.Columns>
</my:DataGrid>
When the cell value change I want to populate some items to the listview ,the TextChanged event is as follows :
当单元格值更改时，我想将一些项目填充到列表视图中，TextChanged 事件如下：
private void txtbxProduct_TextChanged(object sender, TextChangedEventArgs e)
{
TextBox tb = (TextBox)sender;
if (tb.Text.Trim() != "")
{
string qry = "select PL.Record_Id as PList_Id,PM.Record_Id as Product_Id,PM.Product_Code,PM.Product_Name,PTM.Product_Type,PL.Purchase_Rate ,PL.Selling_Rate,PL.MRP from dbo.Tbl_Product_Master PM join Tbl_Product_List PL on PL.Product_Id=PM.Record_Id join Tbl_Product_Type_Master PTM on PTM.Record_Id=PM.Product_Category_Id where PL.Batch_Flag=0 and PM.Is_Del='false'and PM.Is_Active='true' and PM.Product_Name like '%" + tb.Text.Trim() + "%' order by PM.Product_Name ";
DataSet ds = ObjCommon.GetObject.ExecuteQuery_Select(Connection.ConnectionString, qry);
if (ds.Tables[0].Rows.Count > 0)
{
lstvwProductCode.ItemsSource = ds.Tables[0].DefaultView;
lstvwProductCode.Visibility = Visibility.Visible;
}
else
{
lstvwProductCode.ItemsSource = null;
lstvwProductCode.Visibility = Visibility.Collapsed;
}
}
else
{
lstvwProductCode.ItemsSource = null;
lstvwProductCode.Visibility = Visibility.Collapsed;
}
}
When the User enter the down key on the keyboard I want to focus on the listview but It won't fire the Keydown event when I press Down,Back,Space etc keys ,But other keys like alphanumeric keys all working fine .My keydown event is as follows :
当用户在键盘上输入向下键时，我想专注于列表视图，但是当我按下向下、后退、空格等键时它不会触发 Keydown 事件，但其他键（如字母数字键）都可以正常工作。我的 keydown 事件如下：
private void txtbxProduct_KeyDown(object sender, KeyEventArgs e)
{
TextBox tb = (TextBox)sender;
if (e.Key == Key.Escape)
{
tb.Clear();
lstvwProductCode.Visibility = Visibility.Collapsed;
tb.Focus();
}
else if (e.Key == Key.Down)
{
if (lstvwProductCode.Items.Count > 0)
{
lstvwProductCode.SelectedIndex = 0;
lstvwProductCode.Focus();
lstvwProductCode.Visibility = Visibility.Visible;
}
}
}
What I did wrong in my code ?
我在代码中做错了什么？
回答by mohammad jannesary
Instead of that Use PreviewKeyDown
而不是使用PreviewKeyDown
回答by JohnV2
The KeyDownevent is not raised for navigational keys that would normally be handled by WPF, but the PreviewKeyDownevent is. You should set Handled=Trueif you don't want WPF to also handle the key event.
KeyDown对于通常由 WPF 处理的导航键，不会引发该事件，但会引发该PreviewKeyDown事件。Handled=True如果您不希望 WPF 也处理键事件，您应该设置。
