StackPanel中的WPF标签2-n不可见

我正在阅读教程，无论出于何种原因，FirstName、LastName和City的标签在设计时或运行时都不可见。我尝试过删除它们，然后重新添加，得到了相同的结果。有人能看到是什么导致他们被隐藏吗

<Grid Margin="0,0,0,0">
    <Grid.RowDefinitions>
        <RowDefinition Height="73*"/>
        <RowDefinition Height="247*"/>
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="259*"/>
        <ColumnDefinition Width="258*"/>
    </Grid.ColumnDefinitions>
    <Button x:Name="btnSave" Content="Save" Grid.Column="1" HorizontalAlignment="Right" Margin="0,10,10,0" Width="60" Height="22" VerticalAlignment="Top"/>
    <Button x:Name="btnRevert" Content="Revert" Grid.Column="1" HorizontalAlignment="Right" Margin="0,10,86,0" Width="60" RenderTransformOrigin="-0.047,0.36" Height="22" VerticalAlignment="Top"/>
    <Button x:Name="btnAdd" Content="Add" Grid.Column="1" HorizontalAlignment="Right" Margin="0,10,162,0" VerticalAlignment="Top" Width="60"/>
    <Button x:Name="btnDelete" Content="Delete" HorizontalAlignment="Right" Margin="0,10,238,0" VerticalAlignment="Top" Width="60" RenderTransformOrigin="-1.521,0.477" Grid.Column="1"/>
    <Button x:Name="btnFirst" Content="|&lt;" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Width="35"/>
    <Button x:Name="btnFirst_Copy" Content="|&lt;" HorizontalAlignment="Left" Margin="10,10,0,0" VerticalAlignment="Top" Width="35"/>
    <Button x:Name="btnPrevious" Content="&lt;" HorizontalAlignment="Left" Margin="54,10,0,0" VerticalAlignment="Top" Width="35"/>
    <Button x:Name="btnNext" Content="&gt;" HorizontalAlignment="Left" Margin="94,10,0,0" VerticalAlignment="Top" Width="35"/>
    <Button x:Name="btnLast" Content="&gt;|" HorizontalAlignment="Left" Margin="134,10,0,0" VerticalAlignment="Top" Width="35" RenderTransformOrigin="4.102,1.005"/>
    <StackPanel HorizontalAlignment="Left" Height="28" Grid.Row="1" VerticalAlignment="Top" Width="304">
        <Label x:Name="lblCustomerID" Content="Customer ID" Height="28"/>
        <Label x:Name="lblFirstName" Content="First Name" Height="28"/>
        <Label x:Name="lblLastName" Content="Last Name" Height="28"/>
        <Label x:Name="lblCity1" Content="City" Height="28"/>
    </StackPanel>
    <StackPanel Grid.Column="1" HorizontalAlignment="Left" Height="251" Grid.Row="1" VerticalAlignment="Top" Width="297">
        <TextBox x:Name="txtCustomerID" Height="28" TextWrapping="Wrap" Width="Auto" Text="{Binding Path=CustomerID, Mode=OneWay}"/>
        <TextBox x:Name="txtLastName" Height="28" TextWrapping="Wrap" Width="Auto" Text="{Binding Path=LastName}"/>
        <TextBox x:Name="txtFirstName" Height="28" TextWrapping="Wrap" Width="Auto" Text="{Binding Path=FirstName}"/>
        <TextBox x:Name="txtCity" Height="28" TextWrapping="Wrap" Width="Auto" Text="{Binding Path=City}"/>
    </StackPanel>

</Grid>

---

移除

堆叠面板的高度。让它自动填充其高度。您将其设置为
28
，这会使其他孩子被切掉

<StackPanel HorizontalAlignment="Left" Grid.Row="1" VerticalAlignment="Top" Width="304">
    <Label x:Name="lblCustomerID" Content="Customer ID" Height="28"/>
    <Label x:Name="lblFirstName" Content="First Name" Height="28"/>
    <Label x:Name="lblLastName" Content="Last Name" Height="28"/>
    <Label x:Name="lblCity1" Content="City" Height="28"/>
</StackPanel>
<StackPanel Grid.Column="1" HorizontalAlignment="Left" Grid.Row="1" VerticalAlignment="Top" Width="297">
    <TextBox x:Name="txtCustomerID" Height="28" TextWrapping="Wrap" Width="Auto" Text="{Binding Path=CustomerID, Mode=OneWay}"/>
    <TextBox x:Name="txtLastName" Height="28" TextWrapping="Wrap" Width="Auto" Text="{Binding Path=LastName}"/>
    <TextBox x:Name="txtFirstName" Height="28" TextWrapping="Wrap" Width="Auto" Text="{Binding Path=FirstName}"/>
    <TextBox x:Name="txtCity" Height="28" TextWrapping="Wrap" Width="Auto" Text="{Binding Path=City}"/>
</StackPanel>

这是因为您将StackPanel的高度设置为28。移除它，您应该能够看到所有标签。