If you are creating an Office Add-in using VSTO, it is easy to create task panes. But what if you do not want to involve the VSTO Runtime?
Using VSTO makes creating Add-ins very simple, but that simplicity comes at a cost. ClickOnce is a major pain to deploy to users, VSTO Add-ins have a tendency to mysteriously disable themselves, and they load slow.
I have recently switched to using the Visual Studio Add-in wizard, which created Add-ins using the IDTExtensibility2 interface. It requires you to do a bit more legwork, but the generated solution comes with a pre-configured MSI installer project, just asking to be deployed via Group Policy.
My latest project needs to prompt a user to perform an action when Word documents of a certain type are opened. Sure, I could use a pop-up form, but that is so very un-office-like. Taskpanes are a much more integrated solution, but for some reason the documentation and examples on the internet are pretty bad. And confusing. And WAY over complicated.
While working on this, I almost gave up (deleted and then started over once), but persistence and experimentation paid off – I got it to work, and it was much easier than I expected.
The following assumes you have some experience creating Add-ins using IDTExtensibility2.
Create your add-in project (be sure to change the debug properties to run your desired application – it defaults to Visual Studio) , add a reference to System.Windows.Forms, and add the following using statements:
using System.Windows.Forms;
using Microsoft.Office.Core;
First you need to create a user control for your task pane. Microsoft’s example says you have to create a Form and a user control in a separate project, well this is simply not true.
Add a user control to your project. I left the default name of “UserControl1”. Just for fun, we’ll add a button and a label to the user control as well.
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Find the modifiers property on the button and change it to public.
We are doing this so we can access the button’s events from the Add-in, and because I am lazy. (The correct way would be to add a public event to your UserControl1 class, and call it from your private button1 event handler)
Next, modify your Connect class to also implement the ICustomTaskPaneConsumer interface.
public class Connect : Object, Extensibility.IDTExtensibility2, ICustomTaskPaneConsumer
{
//
//
Lets also add a couple more class variables, just to keep life simple (and prevent things from going out of scope unexpectedly)
private object applicationObject;
private object addInInstance;
// New vars for Custom task pane
private ICTPFactory myCtpFactory;
private CustomTaskPane myPane;
private UserControl1 myControl;
Finally, you implement the CTPFactoryAvailable method – this provides you with the ICTPFactory instance that you will use to actually create the task pane. I have also included the example code to create and display our task pane.
public void CTPFactoryAvailable(ICTPFactory CTPFactoryInst)
{
// Store the CTP Factory for future use. You need this to display
// Custom Task Panes
myCtpFactory = CTPFactoryInst;
// Create the task pane using UserControl1 as the contents
// The third parameter, when supplied, is Window object.
myPane = myCtpFactory.CreateCTP("MyAddin1.UserControl1", "My Task Pane", Type.Missing);
//Set the dock position and show the task pane
myPane.DockPosition = Microsoft.Office.Core.MsoCTPDockPosition.msoCTPDockPositionRight;
myPane.Visible = true;
// CustomTaskPane.ContentControl is a reference to the control object
myControl = (UserControl1)myPane.ContentControl;
// assuming UserControl1.button1 is public, add a handler to the click event.
myControl.button1.Click += new EventHandler(button1_Click);
}
And lastly, add an event handler for the click event
void button1_Click(object sender, EventArgs e)
{
MessageBox.Show("Hello World!");
}
Now run your project, and the task pane should be there to greet you. Clicking the button will then display the hello world messagebox.
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In my project, I kept my application logic in a separate class from the Connect class. All you need is a reference to the instance of ICTPFactory supplied by CTPFactoryAvailable to create and hide task panes.
For reference, here is the entire Connect.cs file.
namespace MyAddin1
{
using System;
using Extensibility;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using Microsoft.Office.Core;
/// <summary>
/// The object for implementing an Add-in.
/// </summary>
/// <seealso class='IDTExtensibility2' />
[GuidAttribute("62EFAKE8-FAKE-47EF-82FC-85C5FAKE977E"), ProgId("MyAddin1.Connect")]
public class Connect : Object, Extensibility.IDTExtensibility2, ICustomTaskPaneConsumer
{
public Connect()
{
}
public void OnConnection(object application, Extensibility.ext_ConnectMode connectMode, object addInInst, ref System.Array custom)
{
applicationObject = application;
addInInstance = addInInst;
}
public void OnDisconnection(Extensibility.ext_DisconnectMode disconnectMode, ref System.Array custom)
{
}
public void OnAddInsUpdate(ref System.Array custom)
{
}
public void OnStartupComplete(ref System.Array custom)
{
}
public void OnBeginShutdown(ref System.Array custom)
{
}
public void CTPFactoryAvailable(ICTPFactory CTPFactoryInst)
{
// Store the CTP Factory for future use. You need this to display
// Custom Task Panes
myCtpFactory = CTPFactoryInst;
// Create the task pane using UserControl1 as the contents
// The third parameter, when supplied, is Window object.
myPane = myCtpFactory.CreateCTP("MyAddin1.UserControl1", "My Task Pane", Type.Missing);
//Set the dock position and show the task pane
myPane.DockPosition = Microsoft.Office.Core.MsoCTPDockPosition.msoCTPDockPositionRight;
myPane.Visible = true;
// CustomTaskPane.ContentControl is a reference to the control object
myControl = (UserControl1)myPane.ContentControl;
// assuming UserControl1.button1 is public, add a handler to the click event.
myControl.button1.Click += new EventHandler(button1_Click);
}
void button1_Click(object sender, EventArgs e)
{
MessageBox.Show("Hello World!");
}
private object applicationObject;
private object addInInstance;
// New vars for Custom task pane
private ICTPFactory myCtpFactory;
private CustomTaskPane myPane;
private UserControl1 myControl;
}
}