Func 参数或返回 匿名类 anonymous

How do you declare a Func with an anonymous return type?

Question

I need to be able to do this:

var getHed = () => 
{
    // do stuff
    return new { Property1 = value, Property2 = value2, etc...};
};

var anonymousClass = getHed();

But I get an error which indicates I need to explicitly declare getHed.

How do I declare Func such that T is the anonymous type I am returning?

In case you are curious why I need to do this, it is because I am using 3rd party software that allows customization code, but only within a single method. This can become very difficult to manage. I had the idea that I could use anonymous methods to help keep the procedural code organized. In this case, for it to help, I need a new class, which I cannot define except anonymously.

Answers

As is basically always the case with anonymous types, the solution is to use a generic method, so that you can use method type inference:

public static Func<TResult> DefineFunc<TResult>(Func<TResult> func)
{
    return func;
}

You can now write:

var getHed = DefineFunc(() => 
{
    // do stuff
    return new { Property1 = value, Property2 = value2, etc...};
});

 

 

原文地址：https://www.2cto.com/kf/201207/139227.html

using System; 
 
namespace ConsoleApplication1 
{ 
    class Program 
    { 
        static T CastByExample<T>(object obj, Func<T> example) 
        {   
            return (T)obj; www.2cto.com
        } 
 
        static void f(object p) 
        { 
            var person = CastByExample(p, () => new { Name = "", Age = 0 }); 
            Console.WriteLine("Name={0},Age={1}", person.Name, person.Age); 
        } 
         
        static void Main(string[] args) 
        { 
            var person = new { Name = "Tom", Age = 25 }; 
            f(person); 
        } 
    } 
}