如何获取Datagrid SelectedItem

Question

我想获取存储在DataGrid的第一个单元格中的值。当有人点击我的xaml上的更新Button时，我如何解析该值？

Xaml代码

<DataGrid  Name="GridStream" Style="{StaticResource GridDatabase}" Margin="5" Grid.Row="1" ItemsSource="{Binding}" AutoGenerateColumns="False" >
<DataGrid.Resources>
<Style TargetType="{x:Type DataGridColumnHeader}">
<Setter Property="Background" Value="Turquoise"/>
<Setter Property="Foreground" Value="Black"/>
<Setter Property="FontWeight" Value="SemiBold"/>
<Setter Property="Padding" Value="5"/>
<Setter Property="BorderThickness" Value="0,0,1,2"/>
<Setter Property="BorderBrush" Value="Black"/>
</Style>
</DataGrid.Resources>
<DataGrid.Columns>
<DataGridTextColumn Header="Stream Id" Width="*" Binding="{Binding streamid}"  />
<DataGridTextColumn Header="Stream Name" Width="*" Binding="{Binding streamname}" />
<DataGridTemplateColumn>
<DataGridTemplateColumn.HeaderTemplate>
<DataTemplate>
<TextBlock Text="Action"></TextBlock>                            
</DataTemplate>
</DataGridTemplateColumn.HeaderTemplate>
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Button Name="BtnUpdateStream" Content="Update" Style="{StaticResource BtnForm}" Click="BtnUpdateStream_Click"/>
<Button Name="BtnDeleteStream" Content="Delete" Style="{StaticResource BtnForm}" Click="BtnDeleteStream_Click"/>
</StackPanel>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>

C#代码段

private void BtnUpdateStream_Click(object sender, RoutedEventArgs e)
{
int Id = (GridStream.SelectedItem as member).streamid;
UpdateStream NewForm = new UpdateStream(Id);
Console.WriteLine("The Id Value : {0} is", Id);
//MessageBox.Show(Id);
NewForm.Show();
}

Answer 1

如果DataGrid的ItemsSource是IEnumerable<member>:

private void BtnUpdateStream_Click(object sender, RoutedEventArgs e)
{
var x = GridStream.SelectedItem as member;
if (x != null)
{
int Id = x.streamid;
UpdateStream NewForm = new UpdateStream(Id);
NewForm.Show();
}
}

如果没有选择项，或者当前选择项的类型不是member，则不会显示表单。

如果ItemsSource被设置为DataView，这应该起作用：

var x = GridStream.SelectedItem as DataRowView;
if (x != null)
{
int Id = Convert.ToInt32(x["streamid"]);
UpdateStream NewForm = new UpdateStream(Id);
NewForm.Show();
}

如果绑定到匿名类型的IEnumerable，则可以使用dynamic关键字

private void BtnUpdateStream_Click(object sender, RoutedEventArgs e)
{
dynamic x = GridStream.SelectedItem;
if (x != null)
{
int Id = x.streamid;
//...
}
}