Difference between IComparable and IComparable

Question

I'm new to C# and because of this I found an annoying problem which stop me from making my homework. What's the difference between IComparable and IComparable<K>?

One of my friend used something like this Vector_d<T> where T:IComparable, but everywhere else in source files he used T:IComparable<T>. When I asked him, he didn't know to answer so I have to search somewhere else.

I don't know the exact difference between this two. So I need a hint to know how to use it — Iulian Popescu, Dec 02 '14 at 23:29
What have you not understood in the documentation of both interfaces? The latter is generic. — Tim Schmelter, Dec 02 '14 at 23:32
The one that uses Type is much safer to use. The reason is because without knowing the Type, you have to cast an Object into a class before comparing, which may cause an error. Whereas knowing the Type in advance, you can compare directly. — MikeG, Dec 02 '14 at 23:38
possible duplicate of [When to use IComparable Vs. IComparer](http://stackoverflow.com/questions/538096/when-to-use-icomparablet-vs-icomparert) — Philip Pittle, Dec 02 '14 at 23:43

score 4 · Accepted Answer · answered Dec 02 '14 at 23:35

The first one, IComparable, is from the old .NET days, where there were no generics. It basically allows you to compare any type implementing it to any other type, but possibly it will throw an exception, if the types are not comparable. The generic version, IComparable<>, will only let you compare two values of the same type (or of a derived type), most likely what you want. Old types, such as Int32, used to implement only IComparable, but now they implement both, but IComparable privately, so as not to be called instead of the generic version.

Difference between IComparable and IComparable

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