[dba-VB] C#: Raising events

Hi John --

Here is a promised WinForms sample code with .InvokeRequired and .Invoke:

using System;
using System.Collections.Generic;
using System.Windows.Forms;

namespace WindowsFormsApp
{
    static class Program
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new TestForm());
        }
    }

// TestForm Designer
    partial class TestForm
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be
disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.cmdTest = new System.Windows.Forms.Button();
            this.txtTest = new System.Windows.Forms.TextBox();
            this.SuspendLayout();
            // 
            // cmdTest
            // 
            this.cmdTest.Location = new System.Drawing.Point(128, 205);
            this.cmdTest.Name = "cmdTest";
            this.cmdTest.Size = new System.Drawing.Size(75, 23);
            this.cmdTest.TabIndex = 0;
            this.cmdTest.Text = "&Test";
            this.cmdTest.UseVisualStyleBackColor = true;
            this.cmdTest.Click += new
System.EventHandler(this.cmdTest_Click);
            // 
            // txtTest
            // 
            this.txtTest.Location = new System.Drawing.Point(12, 13);
            this.txtTest.Multiline = true;
            this.txtTest.Name = "txtTest";
            this.txtTest.Size = new System.Drawing.Size(311, 175);
            this.txtTest.TabIndex = 1;
            // 
            // TestForm
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(335, 240);
            this.Controls.Add(this.txtTest);
            this.Controls.Add(this.cmdTest);
            this.Name = "TestForm";
            this.StartPosition =
System.Windows.Forms.FormStartPosition.CenterScreen;
            this.Text = "Test Form";
            this.Load += new System.EventHandler(this.TestForm_Load);
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.Button cmdTest;
        private System.Windows.Forms.TextBox txtTest;
    }

// TestForm Code Behind
    public partial class TestForm : Form
    {
        public TestForm()
        {
            InitializeComponent();
        }

        private My.BusinessLayerClassLib.SpRunnerManager _runner;
        private void TestForm_Load(object sender, EventArgs e)
        {
            _runner = new My.BusinessLayerClassLib.SpRunnerManager();
            _runner.StatusReport +=
                new
EventHandler<My.CoreClassLib.SpRunnerStatusReportEventArgs>(statusReport);
        }


        private void cmdTest_Click(object sender, EventArgs e)
        {
            txtTest.Text = null;
            _runner.Run();
        }

        private void statusReport(object sender,
             My.CoreClassLib.SpRunnerStatusReportEventArgs e)
        {
            string message =
                string.Format("{0}: Processing {1} of {2}...",
                   sender.GetType(), e.CurrentCount, e.MaxCount);

            if (txtTest.InvokeRequired)
            {
                object[] args = { message };
                this.Invoke(new logDelegate(log), args);
            }
            else log(message);
        }

        private delegate void logDelegate(string message);
        private void log(string message)
        {
            txtTest.Text = message + System.Environment.NewLine +
                           txtTest.Text;
        }
    }
}

// classlib1
namespace My.CoreClassLib
{
    public class SpRunnerStatusReportEventArgs : EventArgs
    {
        public int CurrentCount { get; set; }
        public int MaxCount { get; set; }
    }
}

// classlib2
namespace My.UtilsClassLib
{
    public class SpStatusReporter
    {
        public SpStatusReporter(
             EventHandler<My.CoreClassLib.SpRunnerStatusReportEventArgs>
statusReport)
        {
            _statusReport = statusReport;
        }

        private EventHandler<My.CoreClassLib.SpRunnerStatusReportEventArgs>
_statusReport;
        public void ReportStatus(int currentCount, int maxCount)
        {
            if (_statusReport != null)
            {
                My.CoreClassLib.SpRunnerStatusReportEventArgs e =
                    new My.CoreClassLib.SpRunnerStatusReportEventArgs();
                e.CurrentCount = currentCount;
                e.MaxCount = maxCount;
                _statusReport(this, e);
            }
        }
    }
}

// classlib3
namespace My.BusinessLayerClassLib
{
    public class SpRunnerManager
    {
        public EventHandler<My.CoreClassLib.SpRunnerStatusReportEventArgs>
StatusReport;
        private My.UtilsClassLib.SpStatusReporter _reporter;
        public void Run()
        {
            if (_reporter == null)
                _reporter = new
My.UtilsClassLib.SpStatusReporter(StatusReport);

            const int MAX_COUNT = 5;
            for (int i = 1; i <= MAX_COUNT; i++)
            {
                _reporter.ReportStatus(i, MAX_COUNT);
            }
        }
    }
}