Install package programmatically with Merge-Append

Question

I'm trying to develop a small utility that installs an uploaded Sitecore package.
This tool should only install using the Merge-Append option.

This article uses Overwrite. Could you please help me understand what the first argument is for, in the BehaviourOptions method.

I want unavailable items to be created & existing items to be merged by adding a new version (Merge-Append).
For that, will this be the right code.

Sitecore.Install.Items.IItemInstallerEvents events =
       new Sitecore.Install.Items.DefaultItemInstallerEvents(
           new Sitecore.Install.Utils.BehaviourOptions(Sitecore.Install.Utils.InstallMode.Merge, 
 Sitecore.Install.Utils.MergeMode.Append));

Answer 1

First parameter is InstallMode which can be one of 3:

• Overwrite
• Merge
• Skip

Second parameter is MergeMode, only valid for Merge InstallMode. Values can be:

• Merge
• Append
• Overwrite

It's the same like if you choose options in UI. When you select Merge, you can select another option from the dropdown:

I found the image and more information here: https://sitecorecorner.wordpress.com/2015/04/29/sitecore-package-installation-learnings/

Or here:

https://www.partech.nl/nl/publicaties/2012/11/sitecore-package-installation-options-explained