C# 泛型方法,new() 构造函数约束中的类型参数
问题描述:
有没有办法创建一个通用方法,它使用 new()
构造函数约束来要求具有特定类型构造函数的类?
Is there a way to create a Generic Method that uses the new()
constructor constraint to require classes with constructors of specific types?
例如:
我有以下代码:
public T MyGenericMethod<T>(MyClass c) where T : class
{
if (typeof(T).GetConstructor(new Type[] { typeof(MyClass) }) == null)
{
throw new ArgumentException("Invalid class supplied");
}
// ...
}
有没有可能有这样的东西?
Is it possible to have something like this instead?
public T MyGenericMethod<T>(MyClass c) where T : new(MyClass)
{
// ...
}
关于此的建议.请投票,以便我们可以在 C# 中使用此功能!
There's a suggestion regarding this. Please vote so we can have this feature in C#!
答
不是真的;C# 仅支持无参数构造函数约束.
Not really; C# only supports no-args constructor constraints.
我用于泛型 arg 构造函数的解决方法是将构造函数指定为委托:
The workaround I use for generic arg constructors is to specify the constructor as a delegate:
public T MyGenericMethod<T>(MyClass c, Func<MyClass, T> ctor) {
// ...
T newTObj = ctor(c);
// ...
}
然后在调用时:
MyClass c = new MyClass();
MyGenericMethod<OtherClass>(c, co => new OtherClass(co));