Generics method inside of generics method

Question

I have function like this

public static void serialize<T>(T serializeObject){
    //this is the trouble
    SerializableEntity<T> entity = new SerializableEntity<T>(serializeObject);
}

How can I make that in using generics inside of generics? How to accomplish this?

UPDATE

Here the compiler error:

Error image

possible duplicate of [Calling generic method with a type argument known only at execution time](http://stackoverflow.com/questions/325156/calling-generic-method-with-a-type-argument-known-only-at-execution-time) — Habib, May 24 '13 at 06:50
I got compile error with this code SerializableEntity entity = new SerializableEntity(serializeObject); what's wrong? — mrhands, May 24 '13 at 07:04
@mrhands: What compiler error? Please, don't make this a puzzle. — Martin Mulder, May 24 '13 at 07:06
Thanks it has been solved now.. I use that from the dll library I get after I checked the code It tells like the answer below.. — mrhands, May 24 '13 at 07:21

score 8 · Accepted Answer · answered May 24 '13 at 07:14

There is nothing wrong per-se with the code you have: that compiles fine:

class SerializableEntity<T> {
    public SerializableEntity(T obj) { }
}
static class P {
    public static void serialize<T>(T serializeObject) {
        //this is fine...
        SerializableEntity<T> entity =
            new SerializableEntity<T>(serializeObject);
    }
    static void Main() { /*...*/ }
}

So the real question is: what does the compiler say? The most obvious one would be if it says something like:

The type 'T' must be a reference type in order to use it as parameter 'T' in the generic type or method 'SerializableEntity<T>'

which is a "constraint" violation; if that is what you are seeing you need to add the constraints to serialize<T> to prove to the compiler that the constraints are always satisfied. For example, if SerializableEntity<T> is declared as:

class SerializableEntity<T> where T : class
{...}

then you simply transfer that constraint to the method:

public static void serialize<T>(T serializeObject) where T : class
{...}

Note that other constraints are possible, including:

: class
: struct
: SomeBaseType
: ISomeInterface
: new()

@mrhands advice for next time: include the exact compiler error message (ideally copied as text) in the question. Or even better: copy the error message into *google* first, and see what the internet says... — Marc Gravell, May 24 '13 at 07:18

score 1 · Answer 2 · answered May 24 '13 at 07:17

1

You probably have different constraints on T in the method and in the class.

Take in mind that if the class says:

where T  : class, IDisposable

Then the method has to have at least the same where

answered May 24 '13 at 07:17

Adam Tal

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Generics method inside of generics method

2 Answers2