c# – WINFORM或WPF：如何在发出它的类的构造函数中触发自定义事

我有一个userControl11(在winform或wpf中),它有一个ValueChanged自定义事件.如果我把它放在客户端表单中并在form_load中将其值设置为100,它将触发ValueChanged事件.但是如果我在UserControl1的构造函数中设置此值,则不会触发自定义事件.我怎么强迫它这样做？

无论技术原因如何,从功能上来说它确实有意义.如果对象正在从客户端表单未知的某些源初始化其值,并且客户端表单具有绑定到此usercontrol值的文本框,则可以确保它可以随时刷新其文本框,包括表单只加载一个事件处理程序如果没有这个,客户端表单必须在表单加载时为此绑定文本框创建另一个初始化程序.

在winform中我的试验的源代码下面：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace test
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void userControl11_ValueChanged()
        {
            MessageBox.Show(userControl11.Value.ToString());
        }

        private void Form1_Load(object sender,EventArgs e)
        {
           // This will trigger ValueChanged Event
            userControl11.Value = 100;
        }
    }
}



using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;

namespace customevent
{
    [DefaultEvent("ValueChanged")]
    public partial class UserControl1 : UserControl
    {
        private int m_value;

        public delegate void ValueChangedHandler();
        [Category("Action")]
        [Description("Value changed.")]
        public event ValueChangedHandler ValueChanged;

        public int Value
        {
            get { return m_value; }
            set { 
                m_value = value;
                if (ValueChanged != null)
                {
                    ValueChanged();
                }
            }
        }

        public UserControl1()
        {
            InitializeComponent();
            // this won't trigger ValueChanged Event
            this.Value = 100;
        }
        public UserControl1(int iValue)
        {
            this.Value = iValue;
            InitializeComponent();
        }

    }
}

public UserControl1(IEnumerable<Action> subscribers)   {

   this.OnValueChanged(new EventArgs());
   this.Value = 100;
}