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主窗口.xaml

<CheckBox Content="Enable" Height="16" HorizontalAlignment="Left" Margin="190,40,0,0" Name="checkBox_Enable" VerticalAlignment="Top" IsChecked="True" Unchecked="checkBox_Enable_Unchecked" Checked="checkBox_Enable_Checked" />
    <Label Content="Fullscreen:" Height="15" HorizontalAlignment="Left" Margin="227,63,0,0" Name="label3" VerticalAlignment="Top" Width="56" Padding="1" />
    <TextBox HorizontalAlignment="Right" Margin="0,86,243,0" Name="textBox_Hotkey_Fullscreen" Width="33" Height="18" VerticalAlignment="Top" />
    <Label Content="Custom field:" HorizontalAlignment="Left" Margin="227,110,0,136" Name="label5" Padding="1" />
    <TextBox Height="18" HorizontalAlignment="Left" Margin="227,131,0,0" Name="textBox_Hotkey_Customfield" VerticalAlignment="Top" Width="33" />
    <Label Content="Window-related:" HorizontalAlignment="Left" Margin="227,155,0,87" Name="label4" Padding="1" />
    <TextBox HorizontalAlignment="Left" Margin="227,0,0,112" Name="textBox_Hotkey_Windowrelated" Width="33" Height="18" VerticalAlignment="Bottom"  />

主窗口.xaml.cs

    private void checkBox_Enable_Unchecked(object sender, RoutedEventArgs e)
    {
        textBox_Hotkey_Fullscreen.IsEnabled = false;
        textBox_Hotkey_Customfield.IsEnabled = false;
        textBox_Hotkey_Windowrelated.IsEnabled = false;
    }

    //There are no problems after purging this function. However, the controls couldn't be "re-enabled", what obviously makes my concept pointless.  
    private void checkBox_Enable_Checked(object sender, RoutedEventArgs e)
    {

        textBox_Hotkey_Fullscreen.IsEnabled = true; 
        textBox_Hotkey_Customfield.IsEnabled = true;
        textBox_Hotkey_Windowrelated.IsEnabled = true;
    }

为什么它在启动后立即抛出 NullReferenceException？

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2 回答 2

5

我建议使用 Binding like（从 xaml 中删除事件处理程序）

 IsEnabled="{Binding ElementName=checkBox_Enable, Path=IsChecked}"

对于您要使用复选框启用/禁用的每个控件。

于 2012-09-03T14:41:05.720 回答
4

为什么它在启动后立即抛出 NullReferenceException？

因为在CheckBox触发事件时并非所有控件都已加载。

我建议将绑定到CheckBoxbool 并将其他控件IsEnabled绑定到那个（或直接绑定到CheckBox）。

于 2012-09-03T14:35:42.043 回答