How to create PowerPoint add in with C#.Net

Add-in helps us by automating our daily routine work. So let us make simple one.
Create a project of type Shared add-in Visual Studio as shown in a below snapshot.

Click Ok. After clicking a wizard will appear as shown below.

Click next to a language of you choice for development of Add-in. You can select any of the available languages but here, I have selected C# as my preferred language for development of Add-in.

As we are creating add-in for PowerPoint our scope will be only PowerPoint. So Check the Microsoft PowerPoint option only leaving all other unchecked as shown below.

Give a name and description for add-in. We will call our add-in as "Solo Addin" and add a sample description as "Sample Solo Addin"

Choose options for your add-in loading. We will check first option to suggest that PowerPoint should load our add-in when it loads. Second option suggests that the add-in will be available to all users on a machine. You can change this option in deployment deploying.

Next screen shows summary of all the steps we have gone through.

Click on Finish button and that's all. This will create all the necessary framework and code to get started with.

We have main Connect class which will be a mediator between the code we are going to write and PowerPoint. Connect Class will have a unique GUID for an add-in to differentiate between add-ins or to uniquely identify an add-in. You Connect class GUID line will look like the below one.

[GuidAttribute("85D322E5-B30F-48EB-83A4-CB3CD133010F"), ProgId("Solo.Connect")] 

Connect class has main Five event

• OnConnection - fires immediately after Connect Constructor
• OnDisconnection - fires after add-in shutdown
• OnAddInsUpdate - fires when add-in updates
• OnStartupComplete - fires when loading is complete. We will initialize the add-in here.
• OnBeginShutdown - fires when host application begins to shutdown. We will do cleanup things here.

So for now we will just show a MessageBox to know that we are on track. Add reference of System.Windows.Forms dll to the project to get MessageBox work. Add using statement to your Connect class

using System.Windows.Forms;

Show MessageBox on OnStartupComplete event.

/// <summary>
///      Implements the OnStartupComplete method of the IDTExtensibility2 interface.
///      Receives notification that the host application has completed loading.
/// </summary>
/// <param term='custom'>
///      Array of parameters that are host application specific.
/// </param>
/// <seealso class='IDTExtensibility2' />
public void OnStartupComplete(ref System.Array custom)
{
     MessageBox.Show("Hello World!");
}

Build add-in project, Open PowerPoint, and you should get an MessageBox saying "Hello World!"

Conclusion:
This post show how to go get started with PowerPoint add-in development.