MonthCalendar.SelectionRange 数据绑定示例

Posted 2023-03-30

【中文标题】MonthCalendar.SelectionRange 数据绑定示例

【英文标题】：MonthCalendar.SelectionRange databinding example

【发布时间】：2008-12-18 08:04:36

【问题描述】：

如何对 MonthCalendar.SelectionRange 属性执行数据绑定？鉴于该属性的类型为“SelectionRange”，这是一个类，我不知道该怎么做。任何示例将不胜感激。

【参考方案1】：

好吧，MonthCalendar 或 SelectionRange 上似乎没有任何明显的事件，也没有实现 INotifyPropertyChanged，所以它看起来 像数据绑定在这里可能不行。

更新：但是，它确实会引发 DateChanged，因此您可以手动将一些东西连接在一起，或者（更有用）通过子类化控件来以适合绑定的方式公开值和事件。请注意Actual(...) 很有用，因为结束（否则）就在午夜之前，而不是午夜本身......

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Windows.Forms;
class Foo : INotifyPropertyChanged

    public event PropertyChangedEventHandler PropertyChanged;
    protected virtual void OnPropertyChanged(string propertyName)
    
        var handler = PropertyChanged;
        if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
        Debug.WriteLine(ToString());
    
    private void SetField<T>(ref T field, T value, string propertyName)
    
        if (!EqualityComparer<T>.Default.Equals(field, value))
        
            field = value;
            OnPropertyChanged(propertyName);            
        
    
    private DateTime start, end;
    public DateTime Start  get  return start;  set  SetField(ref start, value, "Start");  
    public DateTime End  get  return end;  set  SetField(ref end, value, "End");  


class BindableCalendar : MonthCalendar

    public DateTime ActualSelectionStart
    
        get  return SelectionRange.Start; 
        set  if (ActualSelectionStart != value)  SetSelectionRange(value, ActualSelectionEnd);  
    
    public DateTime ActualSelectionEnd
    
        get  return SelectionRange.End; 
        set  if (ActualSelectionEnd != value)  SetSelectionRange(ActualSelectionStart, value);  
    
    // should really use EventHandlerList here...
    public event EventHandler ActualSelectionStartChanged, ActualSelectionEndChanged;

    DateTime lastKnownStart, lastKnownEnd;
    protected override void OnDateChanged(DateRangeEventArgs drevent)
    
        base.OnDateChanged(drevent);
        if (lastKnownStart != drevent.Start)
        
            if (ActualSelectionStartChanged != null) ActualSelectionStartChanged(this, EventArgs.Empty);
            lastKnownStart = drevent.Start;
        
        if (lastKnownEnd != drevent.End)
        
            if (ActualSelectionEndChanged != null) ActualSelectionEndChanged(this, EventArgs.Empty);
            lastKnownEnd = drevent.End;
        
    



static class Program

    [STAThread]
    static void Main()
    

        Application.EnableVisualStyles();
        MonthCalendar cal;
        Button btn;
        using (Form form = new Form
        
            Controls = 
                (cal = new BindableCalendar  Dock = DockStyle.Fill, MaxSelectionCount = 10 ),
                (btn = new Button  Dock = DockStyle.Bottom, Text = "thwack")
            
        )
        
            Foo foo = new Foo  Start = DateTime.Today, End = DateTime.Today.AddDays(1) ;
            cal.DataBindings.Add("ActualSelectionStart", foo, "Start").DataSourceUpdateMode = DataSourceUpdateMode.OnPropertyChanged;
            cal.DataBindings.Add("ActualSelectionEnd", foo, "End").DataSourceUpdateMode = DataSourceUpdateMode.OnPropertyChanged;
            btn.Click += delegate
            
                foo.Start = foo.Start.AddDays(1);
                foo.End = foo.End.AddDays(1);
            ;
            Application.Run(form);
        
    

【参考方案2】：

对我来说，这似乎很简单。我只是绑定了 MonthCalendar 组件的 SelectionStart 和 SelectionEnd 属性。

this.Calendar1.DataBindings.Add(new System.Windows.Forms.Binding("SelectionStart",
bindingSource, "DateField", true));
this.Calendar1.DataBindings.Add(new System.Windows.Forms.Binding("SelectionEnd",
bindingSource, "DateField", true));