EF6-在清单中包含对象 <Func<T, object> &gt;

Question

I want to Include objects to query by "Funcs", not by strings. This time I do it that way ( pagedListFunc.Includes is List<string> ):

foreach (var include in pagedListFunc.Includes)
{
    query = query.Include(include);
}

I want to use this list:

IncludeFuncs = new List<Func<Dicts, object>>()
{
    x => x.AspNetUsers,
    x => x.DictDomains
};

When I try to use pagedListFunc.IncludeFuncs (in fact, it's above list: List<Func<T, object>> ):

foreach (var include in pagedListFunc.IncludeFuncs)
{
    query = query.Include(x => include(x)); // doesn't work
    // or
    query = query.Include(include); // wrong parameter error
}

How to use IncludeFuncs properly?

Answer 1

The correct type for the parameter is Expression<Func<T, object>> , which means that your IncludeFuncs must be of type List<Expression<Func<Dicts, object>>() as stated in the docs .

As a sidenote, instead of using a List , this would be a nice use case for the params keyword and a simple array. With that approach, you could specify a variable number of arguments when calling the method.

This would look like this for example (pseudocode):

public Dicts GetById(int id, params Expression<Func<Dicts, object>>[] includeProps)
{
    ...
    foreach(var include in includeProps)
    {
        query = query.Include(include);
    }
    ...
}

Usage:

GetById(1, x => x.AspNetUsers, x => x.DictDomains);