WPF C中的Tabcontrol＃

现在我正在使用tabcontrol来安排我的UI。首先，我把我的按钮放在我的tabcontrol之外;然而，当我把按钮放入tabcontrol时，它给出了消息Object reference not set to an object instance。有谁知道我为什么收到这条消息？WPF C中的Tabcontrol＃

编辑

下面是我的XAML：

<Window x:Class="StudySystem.Window1" 
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
     Title="UI" Height="600" Width="811" mc:Ignorable="d" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:my="clr-namespace:StudySystem" Loaded="Window_Loaded"> 
    <Grid Width="791"> 
     <Grid.RowDefinitions> 
      <RowDefinition Height="129*" /> 
      <RowDefinition Height="432*" /> 
     </Grid.RowDefinitions> 
     <TabControl Margin="2,0,0,42"> 
      <TabItem Header="Book Info" > 
       <Grid ShowGridLines="False"> 
        <Grid.ColumnDefinitions> 
         <ColumnDefinition Width="100" /> 
         <ColumnDefinition Width="150" /> 
         <ColumnDefinition Width="150" /> 
         <ColumnDefinition Width="178*" /> 
        </Grid.ColumnDefinitions> 
        <Grid.RowDefinitions> 
         <RowDefinition Height="Auto" /> 
         <RowDefinition Height="Auto" /> 
         <RowDefinition Height="Auto" /> 
         <RowDefinition Height="Auto" /> 
         <RowDefinition Height="Auto" /> 
         <RowDefinition Height="22*" /> 
        </Grid.RowDefinitions> 
        <TextBlock Text="Book Code:" Height="25" Margin="0,15,0,45"></TextBlock> 
        <TextBox Name="txtCode" Grid.Column="1" Margin="2,15,0,51" 
          Width="148"></TextBox> 
        <TextBlock Grid.Row="1" Text="Title:" Margin="0,1,0,33" Height="18"></TextBlock> 
        <TextBox Name="txtTitle" Grid.Row="1" Grid.Column="1" Margin="2,1,148,32" Grid.ColumnSpan="2"></TextBox> 

        <TextBlock Grid.Row="3" Text="Author:" Margin="0,5,0,33" Height="17"></TextBlock> 
        <TextBox Name="txtAuthor" Grid.Row="3" Grid.Column="1" Margin="0,6,0,30"></TextBox> 
        <Button Content="OK" Grid.Row="4" Grid.Column="1" Margin="0,1,0,37"></Button> 
       </Grid> 
      </TabItem> 
     </TabControl> 
    </Grid> 
</Window>

来源

2013-04-28 CYB

你的代码看起来没问题。问题是别的地方。 – 2013-04-28 13:20:36

只是看看异常的堆栈跟踪http://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-in-net – 2013-04-28 13:21:24

你在后面的代码中改变了什么？ – MichaelS 2013-04-28 13:21:39

我以前见过这个，它的代码创建表单之前，它引用您的形式的东西。检查你打电话的顺序。

来源

2013-04-28 14:44:00 Badmiral

但它只是在intializecompnent函数损坏 – CYB 2013-04-28 14:53:04

深入了解Windows标签我已经加入此代码对我来说它的做工精细...

<Grid Width="auto"> 
    <Grid.RowDefinitions> 
     <RowDefinition Height="*" /> 
     <RowDefinition Height="432*" /> 
    </Grid.RowDefinitions> 
    <TabControl Grid.Row="1"> 
     <TabItem Header="Book Info" > 
      <Grid ShowGridLines="False"> 
       <Grid.ColumnDefinitions> 
        <ColumnDefinition Width="100" /> 
        <ColumnDefinition Width="150" /> 
        <ColumnDefinition Width="150" /> 
        <ColumnDefinition Width="178*" /> 
       </Grid.ColumnDefinitions> 
       <Grid.RowDefinitions> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="Auto" /> 
        <RowDefinition Height="22*" /> 
       </Grid.RowDefinitions> 
       <TextBlock Text="Book Code:" Height="25" Margin="0,15,0,45"> </TextBlock> 
       <TextBox Name="txtCode" Grid.Column="1" Margin="2,15,0,51" 
         Width="148"></TextBox> 
       <TextBlock Grid.Row="1" Text="Title:" Margin="0,1,0,33" Height="18"></TextBlock> 
       <TextBox Name="txtTitle" Grid.Row="1" Grid.Column="1" Margin="2,1,148,32" Grid.ColumnSpan="2"></TextBox> 

       <TextBlock Grid.Row="3" Text="Author:" Margin="0,5,0,33" Height="17"></TextBlock> 
       <TextBox Name="txtAuthor" Grid.Row="3" Grid.Column="1" Margin="0,6,0,30"></TextBox> 
       <Button Content="OK" Grid.Row="4" Grid.Column="1" Margin="0,1,0,37"></Button> 
       </Grid> 
      </TabItem> 
     </TabControl> 
    </Grid>

你在window_loaded提到？

来源

2013-04-28 14:44:28

我加载我的数据库在window_loaded – CYB 2013-04-28 14:45:40

WPF C中的Tabcontrol＃

回答

相关问题