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What is the difference between explicit and implicit interface implementation (C# interface interview questions)?

• By Shiv Prasad Koirala in C#
• Oct 27th, 2013
• 10714
• 0

Sometimes this question is twisted and asked in a different way "Can we implement interfaces with same method names in c# ?".

As all of us know one of the advantage of using interfaces is to support multiple inheritance where one class will implement more than one interface.

Example:

public interface I1

void method1();
}

public interface I2

void method2();
}

public class MyClass:I1,I2

public void method1()

//do something here
}

                public void method2()

               

                                //do something here

                }

}

.

.

I1 i=new MyClass();

i.method1(); //method2 will not be available.

 

I2 i2=new MyClass();

i2.method2(); //method1 will not be available.

 

These kind of implementation is called as implicit interface implementation.

Now let's say both of these interface have a method called Method3, Now the question is how they will be defined in MyClass.

public class MyClass:I1,I2

public void method1() // Because of I1

//do something here
}

                public void method2() //Because of I2

               

                                //do something here

                }

                public void method3() //Because of both I1 and I2

               

                                //do Something here

                }

}

 

In above code we are using Implicit implementation so both of the following call will do same thing.

I1 i=new MyClass();

i.method3();

 

I2 i2=new MyClass();

i2.method3();

 

Now what if we want to write separate implementation for both the interface methods. There comes explicit interface implementation.

public class MyClass:I1,I2

public void method1() // Because of I1

//do something here
}

                public void method2() //Because of I2

               

                                //do something here

                }

public void I1.method3() // Because of I1

               

                                //do something here

                }

public void I2.method3() // Because of I2

               

                                //do something here

                }

}

A big thanks to questpond.com to provide this C# interface interview question.

Also watch our latest video on C# interview questions & answers :-