Question

How could I refactor this function so it could take any many to many parameters?

Program has many to many parameters as in Age, Color, etc…

So I have this function:

public int GetAgesOnProgram(IEnumerable<Program> ProgramList)
{
    return (from x in ProgramList
        where x.Ages.Any()
        select x.Ages).Count();
}

but I also need this one:

public int GetColorsOnProgram(IEnumerable<Program> ProgramList)
{
    return (from x in ProgramList
        where x.Colors.Any()
        select x.Colors).Count();
}

As I have up to 10 many to many relationships in Program, I guess it makes sense to have a single function that handles that?

EDIT:
How could I return the Age or Color List, rather than an int as in:

public IEnumerable<Color> GetColorsOnProgram(IEnumerable<Program> ProgramList)
{
    return (from x in ProgramList
        where x.Colors.Any()
        select x.Colors);
}

Answer 1

You can change your function to:

public int GetCountOnProgram(IEnumerable<Program> ProgramList, Func<Program,bool> whereClause)
{
    return ProgramList.Where(whereClause).Count();
}

And then call it with:

GetCountOnProgram(programList, x => x.Ages.Any());