Question

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Constructor vs. Factory in .NET Framework

I understand factory patten and have implemented it but couldn’t get what benefit it will bring. For example instead of:

MyType1 obj=new Mytype1();
MyType2 obj=new Mytype2();

writing:

IMyType obj1 = Factory.Create(1);
IMyType obj2 = Factory.Create(2);

Is it something I have missed or not conceive. Can you please put your own experience example.

Answer 1

Some benefits of the factory pattern:

1. You can keep track of the objects you create. If you want to re-use objects or enforce a limit on the number of objects created, the factory can enforce that.
2. You can control how objects are created. If there are some parameters used to create the objects, you can return an existing object when clients pass in the same parameters for an object that has already been created.
3. You can have the factory return an interface but internally create different types of objects that support the interface.