monodevelop編譯錯誤； 如果存在引用，為什么會丟失匯編引用？

Question

我從MonoDevelop創建了一個GTK＃2.0項目，它生成了兩個文件：

Program.cs

using System;
using Gtk;

namespace Application
{
    class MainClass
    {
        public static void Main(string[] args)
        {
            Application.Init();
            MainWindow win = new MainWindow();
            win.Show();
            Application.Run();
        }
    }
}

MainWindow.cs：

using System;
using Gtk;

public partial class MainWindow : Gtk.Window
{
    public MainWindow() : base(Gtk.WindowType.Toplevel)
    {
        Build();
    }

    protected void OnDeleteEvent(object sender, DeleteEventArgs a)
    {
        Application.Quit();
        a.RetVal = true;
    }
}

我按下了“調試”按鈕，未修改任何代碼。 然后編譯器打印此：

The type or namespace name `Init' does not exist in the namespace `Application'. Are you missing an assembly reference? (CS0234)
The type or namespace name `Run' does not exist in the namespace `Application'. Are you missing an assembly reference? (CS0234)
The type or namespace name `Quit' does not exist in the namespace `Application'. Are you missing an assembly reference? (CS0234)

我在“解決方案”選項卡上看到了“參考”列表，並且存在Gtk.Application.Init，Run，Quit。 那為什么會發生這個錯誤呢？

Answer 1

將Program.cs修改為：

using System;
using Gtk;

namespace Application
{
    class MainClass
    {
        public static void Main(string[] args)
        {
            Gtk.Application.Init();
            MainWindow win = new MainWindow();
            win.Show();
            Gtk.Application.Run();
        }
    }
}

修改MainWindow.cs為：

using System;
using Gtk;

public partial class MainWindow : Gtk.Window
{
    public MainWindow() : base(Gtk.WindowType.Toplevel)
    {
        Build();
    }

    protected void OnDeleteEvent(object sender, DeleteEventArgs a)
    {
        Gtk.Application.Quit();
        a.RetVal = true;
    }
}