MessageBox.Show method with Help Button not opening help file from a VSTO Word Add-In

Question

The following works in a Winform application but not in my VSTO 2008 Word Add-In. You can use this MSDN Example for you testing. Also for your test, you can copy the mspaint.chm file from C:\WINDOWS\Help folder.

MessageBox.Show("Test message", "Test title", MessageBoxButtons.OK, MessageBoxIcon.Information, MessageBoxDefaultButton.Button1, 0, "myHelpFile.chm", HelpNavigator.TopicId, "1001");

When I click on the help button of the MessagBox in my Winform applicaion, the help file opens showing the correct topic but nothing happens when I click on the Help Button of the MessageBox in my Add-In. I have tried using the above code from the ThisAddIn.cs file and also in a WinForm included in my Add-In.

I am using Office 2003 and the Add-In is application-level. I have copied the MyHelpFile.chm file in bin\Debug directory of both my application Winform and Add-In applications. I have tried it hard coding the full path of the file in the above code and also programmatically accessing the path of the file and storing it in a variable and replacing the “MyHelpFile.chm “with that variable.

Please help. Thanks,

Nam

Answer 1

Hi namwam,

Thanks for posting in the MSDN Forum.

I'm preparing the environment to reproduce your issue now. There might be some time delay. I will come back as fast as I can, appreciate for your patience.

Have a good day,

Tom

---

Tom Xu [MSFT]
MSDN Community Support | Feedback to us

Answer 2

Hi namwam,

I tried to reproduce your issue. I found it has limitation to show Help file via a MessageBox. The code alse doesn't work in a Form_Load method of a Windows Form application. If you use Help.ShowHelp you help file will show.

using System;
using System.Windows.Forms;
using Microsoft.VisualStudio.Tools.Applications.Runtime;
using Excel = Microsoft.Office.Interop.Excel;
using Office = Microsoft.Office.Core;

namespace ExcelAddIn1
{
    public partial class ThisAddIn
    {
        private Office.CommandBar nb = null;
        private Office.CommandBarControl bt = null;
        private Office.CommandBarButton btn = null;

        private void ThisAddIn_Startup(object sender, System.EventArgs e)
        {
            #region VSTO generated code

            this.Application = (Excel.Application)Microsoft.Office.Tools.Excel.ExcelLocale1033Proxy.Wrap(typeof(Excel.Application), this.Application);

            #endregion
            Excel.Application xlApp = Application;
            nb = xlApp.CommandBars["Worksheet Menu Bar"];
            bt = nb.Controls.Add(Office.MsoControlType.msoControlPopup, Type.Missing, Type.Missing, Type.Missing, true);
            bt.Caption = "test";
            btn = (Office.CommandBarButton)((Office.CommandBarPopup)bt).Controls.Add(Office.MsoControlType.msoControlButton, Type.Missing, Type.Missing, Type.Missing, true);
            btn.Caption = "Alert";
            btn.Click += new Microsoft.Office.Core._CommandBarButtonEvents_ClickEventHandler(btn_Click);
        }

        void btn_Click(Microsoft.Office.Core.CommandBarButton Ctrl, ref bool CancelDefault)
        {
            //The commented code will not work!
            //MessageBox.Show(Environment.CurrentDirectory, "Test", MessageBoxButtons.OK, MessageBoxIcon.Question,
            //    MessageBoxDefaultButton.Button1, 0, "test.chm", HelpNavigator.TopicId, "1001");
            Form1 frm = new Form1();
            frm.Show();
            Help.ShowHelp(null, "test.chm",HelpNavigator.TopicId, "1001");
        }

        private void ThisAddIn_Shutdown(object sender, System.EventArgs e)
        {
        }

        #region VSTO generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InternalStartup()
        {
            this.Startup += new System.EventHandler(ThisAddIn_Startup);
            this.Shutdown += new System.EventHandler(ThisAddIn_Shutdown);
        }
        
        #endregion
    }
}

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

namespace ExcelAddIn1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            MessageBox.Show(Environment.CurrentDirectory, "Test", MessageBoxButtons.OK, MessageBoxIcon.Question,
                MessageBoxDefaultButton.Button1, 0, "test.chm", HelpNavigator.TopicId, "1001");
        }

        private void Form1_Load(object sender, EventArgs e)
        {
			//The commented code will not work
            //MessageBox.Show(Environment.CurrentDirectory, "Test", MessageBoxButtons.OK, MessageBoxIcon.Question,
            //    MessageBoxDefaultButton.Button1, 0, "test.chm", HelpNavigator.TopicId, "1001");
        }
    }
}

And the correct path of the Help file is MyDocuments folder.

I hope it can help you.

Have a good day,

Tom

---

Tom Xu [MSFT]
MSDN Community Support | Feedback to us