c# - 为什么不能将 Windows 窗体的大小绑定(bind)到 ApplicationSettings？

Question

更新:已解决，有代码

I got it working, see my answer below for the code...

原帖

正如 Tundey 在 his answer to my last question 中指出的那样，您几乎可以毫不费力地将 Windows 窗体控件的所有内容绑定(bind)到 ApplicationSettings。那么真的没有办法用表单大小来做到这一点吗？ This tutorial 表示您需要显式处理 Size，以便在窗口最大化或最小化时可以保存 RestoreBounds 而不是 size。但是，我希望我可以使用如下属性:

public Size RestoreSize
{
    get
    {
        if (this.WindowState == FormWindowState.Normal)
        {
            return this.Size;
        }
        else
        {
            return this.RestoreBounds.Size;
        }
    }
    set
    {
        ...
    }
}

但我看不到在设计器中绑定(bind)它的方法(PropertyBinding 列表中明显缺少 Size)。

Answer 1

我终于想出了一个 Form 子类来一劳永逸地解决这个问题。要使用它:

1. 继承自 RestorableForm 而不是 Form。
2. 将 (ApplicationSettings) -> (PropertyBinding) 中的绑定(bind)添加到 WindowRestoreState。
3. 在窗口即将关闭时调用 Properties.Settings.Default.Save()。

现在窗口位置和状态将在 session 之间被记住。根据下面其他发帖人的建议，我加入了一个 ConstrainToScreen 函数，以确保窗口在恢复时能够很好地适应可用的显示。

代码

// Consider this code public domain. If you want, you can even tell
// your boss, attractive women, or the other guy in your cube that
// you wrote it. Enjoy!

using System;
using System.Windows.Forms;
using System.ComponentModel;
using System.Drawing;

namespace Utilities
{
    public class RestorableForm : Form, INotifyPropertyChanged
    {
        // We invoke this event when the binding needs to be updated.
        public event PropertyChangedEventHandler PropertyChanged;

        // This stores the last window position and state
        private WindowRestoreStateInfo windowRestoreState;

        // Now we define the property that we will bind to our settings.
        [Browsable(false)]        // Don't show it in the Properties list
        [SettingsBindable(true)]  // But do enable binding to settings
        public WindowRestoreStateInfo WindowRestoreState
        {
            get { return windowRestoreState; }
            set
            {
                windowRestoreState = value;
                if (PropertyChanged != null)
                {
                    // If anybody's listening, let them know the
                    // binding needs to be updated:
                    PropertyChanged(this,
                        new PropertyChangedEventArgs("WindowRestoreState"));
                }
            }
        }

        protected override void OnClosing(CancelEventArgs e)
        {
            WindowRestoreState = new WindowRestoreStateInfo();
            WindowRestoreState.Bounds
                = WindowState == FormWindowState.Normal ?
                  Bounds : RestoreBounds;
            WindowRestoreState.WindowState = WindowState;

            base.OnClosing(e);
        }

        protected override void OnLoad(EventArgs e)
        {
            base.OnLoad(e);

            if (WindowRestoreState != null)
            {
                Bounds = ConstrainToScreen(WindowRestoreState.Bounds);
                WindowState = WindowRestoreState.WindowState;
            }
        }

        // This helper class stores both position and state.
        // That way, we only have to set one binding.
        public class WindowRestoreStateInfo
        {
            Rectangle bounds;
            public Rectangle Bounds
            {
                get { return bounds; }
                set { bounds = value; }
            }

            FormWindowState windowState;
            public FormWindowState WindowState
            {
                get { return windowState; }
                set { windowState = value; }
            }
        }

        private Rectangle ConstrainToScreen(Rectangle bounds)
        {
            Screen screen = Screen.FromRectangle(WindowRestoreState.Bounds);
            Rectangle workingArea = screen.WorkingArea;

            int width = Math.Min(bounds.Width, workingArea.Width);
            int height = Math.Min(bounds.Height, workingArea.Height);

            // mmm....minimax
            int left = Math.Min(workingArea.Right - width,
                                Math.Max(bounds.Left, workingArea.Left));
            int top = Math.Min(workingArea.Bottom - height,
                                Math.Max(bounds.Top, workingArea.Top));

            return new Rectangle(left, top, width, height);
        }
    }
}

设置绑定(bind)引用

• SettingsBindableAttribute
• INotifyPropertyChanged