c# - 我尝试在C#中进行编译时，此错误是什么意思？

Question

这是代码

namespace FitnessApp
{
    /// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
        Database db = new Database();
        Exercise exercise = db.getAllMuscleGroups();
        lbMuscleGroup.Items.Add(exercise);
    }
}

}

和xaml代码:

<Window x:Class="FitnessApp.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:FitnessApp"
    mc:Ignorable="d"
    Title="MainWindow" Height="450" Width="800">
<Grid>
    <ListBox x:Name="lbMuscleGroup" HorizontalAlignment="Left" Height="106" Margin="86,144,0,0" VerticalAlignment="Top" Width="145" SelectionChanged="lbMuscleGroup_SelectionChanged"/>
    <ListBox x:Name="lbSelected" HorizontalAlignment="Left" Height="100" Margin="334,149,0,0" VerticalAlignment="Top" Width="140"/>
</Grid>

这是错误:

Error CS1061 'MainWindow' does not contain a definition for 'lbMuscleGroup_SelectionChanged' and no accessible extension method 'lbMuscleGroup_SelectionChanged' accepting a first argument of type 'MainWindow' could be found (are you missing a using directive or an assembly reference?) FitnessApp C:\Users\Remco\OneDrive - Office 365 Fontys\FUN12\Killer-app\FitnessApp\FitnessApp\MainWindow.xaml 10 Active

如何解决此错误？不断收到此错误。很烦人。

Answer 1

在您的XAML代码中，您将“lblMuscleGroup”定义为具有on change事件:

SelectionChanged="lbMuscleGroup_SelectionChanged"

在MainWindow代码中，您没有定义此名称，因此它说:“嘿!我正在寻找您说过的东西，但您没有，您忘了什么吗？”

因此，添加以下内容应该可以:

private void lbMuscleGroup_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    //something happens
}

或者，您可以从XAML中删除“SelectionChanged =“lbMuscleGroup_SelectionChanged”部分。

希望这可以帮助!