interfaces and IComparable

Question

Continuing in my develpment of C# and .Net I am struggling to understand the purpose of interfaces but particularly the IComparable interface. If the interface is implemented it provides a comparison method but what advantage does this provide over the comparison methods String.CompareTo or Int32.CompareTo. These can be called without implementing IComparable. Can someone explain? Have searched internet and not found a useful explanation.
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Amit Choudhary · Answer

By marking the answer as liked post you can favor me back.. Thanks.. :)

Darren Murray · Answer

yes i think I unerstand now...i couldn;t understand how everything fit together but I think i got it now. thanks!

Amit Choudhary · Answer

In the article you are referring Ans to WHY? : they are comparing two objects of class Employee based on the EmpID attribute. Ans to How? : By writing the logic in override of CompareTo method of IComparable interface. Ans to  what is being passed to the method to create the temp instance ? : The object need to be compared is passed in CompareTo as an argument and then explicitly converting it to Employee class type. Look at it: public int CompareTo( object obj) { Employee temp=(Employee)obj; ..... } Hope you got all your answers and might clearing your doubts. Please mark Do you like this post? if it really helped you.

Darren Murray · Answer

Understand. Got it. Can you help me breakdown the follwing sample code though: http://www.c-sharpcorner.com/UploadFile/prasadh/IComparablePSD12062005010125AM/IComparablePSD.aspx My understanding is the Array.Sort(employees) invokes the CompareTo method in the Employee class. But how/why? Also in the CompareTo method the method is comparing t his .Id and temp.Id. I am not understanding where each value is coming from (what is being passed to the method to create the temp instance?)

Amit Choudhary · Answer

Hi friend  String.CompareTo or Int32.CompareTo. These can be called without implementing IComparable.  Yes these can be called directly because Class String and Int32 already implemented the IComparable interface. if you want your class say.. TestClass and you want to provide the action to comapre objects then you can not directly call the CompareTo method with you custom class object. Implement the IComparable interface the you are good to go. you'll be able to write TestClass.CompareTo() as we do using inbuilt classes. Thanks..

Sam Hobbs · Answer

If you need to ask what is the advantage then there is absolutely no advantage. If there is an advantage for you then you won't need to ask.

Suthish Nair · Answer

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