How to conditionally pass parameters into a func array

Question

I have method that expects the following parameters:

public IQueryable<TEntity> GetAllIncluding(params Expression<Func<TEntity, object>>[] includeProperties)
{
    foreach (var includeProperty in includeProperties)
    {
        dbSet.Include(includeProperty);
    }
    return dbSet;
}

Here's how I pass in my params:

IQueryable<User> users = repo.GetAllIncluding(u => u.EmailNotices, u => u.EmailTemplatePlaceholders, u => u.Actions);

However, I need to be able to check certain conditions before I pass them in or not.

For example, if I have a variable useEmailNotices = false, then I don't want to pass in EmailNotices but if it's true then I do. I need to do this for all three. I know there's a long way to do this but I was hoping that there was a one line short way or a param builder function or something of that nature.

Answer 1

What about changing the signature of the method to

public IQueryable<TEntity> GetAllIncluding(IEnumerable<Expression<Func<TEntity, object>>> includeProperties)

defining your conditional logic elsewhere

var args = new List<Expression<Func<TEntity, object>>>();
if (useEmailNotices)
    args.Add(u => u.EmailNotices);

and then simply calling the method like

IQueryable<User> users = repo.GetAllIncluding(args);

Answer 2

Instead of Params, use a List<T>, declared with the actual entity you wish to pass in:

var funcList = new List<Expression<Func<User, object>>>();

funcList.add(u => u.EmailTemplatePlaceholders);

if (useEmailNotices)
    funcList.add(u => u.EmailNotices);

And the method signature would now be:

public IQueryable<TEntity> GetAllIncluding(List<Expression<Func<TEntity, object>> includeProperties)
{
    foreach( ... )
}