Read original post by Santhosh Kumar Jayaraman at The Code Project
Recently in our project, we wanted to allow the user to select multiple values in a list. But the list should be populated inside a grid row. So we didn’t want to use a listbox and also we were not interested in third party tools. Instead of that, we wanted to use a multiselect combobox. When I browsed through various blogs, forums, etc., I got a few good codes, but none of them worked with MVVM pattern. In those articles, most of the datasource bindings were done at code behind. So I have changes to those existing code to support MVVM. In this article, I am going to explain how we can create a multi select combobox user control step by step. This article will also help people who have recently started learning WPF, since I have explained how we can create styles and dependency properties.