使用Checkboxes以编程方式过滤GridView

I'm creating a project tracker ASP.net wbsite with C# for my codebehind. My default view has a GridView that queries a SQL Server DB, and one of the columns is Project Status (ProjStatus), which can have 5 different options (In Progress, Pending, Complete, Postponed, Cancelled). I'm creating a project tracker ASP.net wbsite w