C＃反射和Func <object,bool> 会员

Question

I have 3 classes, each of which has the same function fields:

class A {
    Func<sampleobject,bool> alpha = c=>c.some1 == something;
    Func<sampleobject,bool> beta = c=>c.some1 == something;
}
class B {
    Func<sampleobject,bool> alpha = c=>c.some1 == something;
    Func<sampleobject,bool> beta = c=>c.some1 == something;
}
class C {
    Func<sampleobject,bool> alpha = c=>c.some1 == something;
    Func<sampleobject,bool> beta = c=>c.some1 == something;
}

I have a factory that will get me the proper class. There's also another method that will determine which function of the class gets called.

dbcontext.sampleobjects.where(Factory(class).ReflectionFunction(memberName));

I was able to use reflection to get the member name via:

var prop = this.GetType().GetMember("alpha");

I just don't know how to use this or what to call to be able to be used in the "WHERE" statement like if I would call it directly.

dbcontext.sampleobjects.Where(instanceofA.alpha);

Answer 1

var prop = this.GetType().GetMember("alpha");

is a bit misleading - it is a field, not a property. However, you can get its actual value with:

var func = (Func<sampleobject, bool>)prop.GetValue(this);

and then use it in the Where call:

dbcontext.sampleobjects.Where(func);

(or use it directly on an object like this:)

sampleobject obj = null; // or some other value
var result = func(obj);