You can add operators to your own types, allowing them to be used much like the operators with the built-in C types. To understand the need for operator overloading, imagine that you need to perform matrix math operations in your program.

Chapter 13 - Operator Overloading | C Sharp (Programming Language) | C (Programming Language)

You could instantiate a couple 2-dimensional arrays and do what you need. However, add the requirement for the matrix behavior to be reusable. Because you need to do the same thing in other programs and want to take advantage of the fact that you have already written the code, you will want to create a new type. So, you create a Matrix type, which could be a class or a struct.

Now consider how this Matrix type would be used. You would want to initialize two or more Matrix instances with data and then do a mathematical operation with them, such as add or get a dot product.

To accomplish the mathematical operation, you could implement an Add , DotProduct , and other methods to get the job done. Using the classes would look something like this:. The problem with using methods like this is that it is cumbersome, verbose, and unnatural for the problem you are trying to solve. The following shows how the syntax appears using operators:. This is much more elegant and easier to work with.

A Beginner's Tutorial on Operator Overloading in C# - CodeProject

For a single operation, one could argue that the amount of work to implement one syntax over the other is not that great. However, when chaining multiple mathematical operations, the syntax is much simpler. Additionally, if the primary users of your type are mathematicians and scientists, operators are more intuitive and natural.

A lot of the discussion, so far, has emphasized the need to write code and implement types in the simplest and most natural way possible. A very important concept to remember is that although operators are simple, they are not always natural. In the example above it made sense to use operators with the Matrix type. This is similar to the reason why operators make sense with the built-in types such as int and float. However, it is easy to abuse operators and create convoluted implementations that are hard for anyone, including the original author, to understand.

For an example of a bad implementation, consider a Car class that needs an implementation allowing you to park the car in a garage. It would be a mistake to think that the following implementation was smart:. This is bad code. No one will truly understand what it means and they will not think it is clever. Furthermore, it hurts the maintainability of the application because it is so hard to understand what the code does.

The idea is this: Use operators where they lend understanding and simplicity to a type. Otherwise, do not use them. The syntax required to implement an overloaded operator is much the same as a static method with a couple exceptions.

You must use the operator keyword and specify the operator symbol being overloaded.

Notice that the method is static. Use the keyword operator after specifying the return type, Matrix in this case. Following the operator keyword, the actual operator symbol is specified and then there is a set of parameters to be operated on. See Listing for a full example of how to implement and use an overloaded operator.

The operator is static , which is the only way it can and should be declared because an operator belongs to the type and not a particular instance. There are just a few rules you have to follow when implementing operator overloads. The parameter types are both of the enclosing type, Matrix. The implementation of the operator overload creates a new instance of the return type and performs a matrix add.

C enforces certain rules when you overload operators. One rule is that you must implement the operator overload in the type that will use it. This is sensible because it makes the type self-contained. Another rule is that you must implement matching operators. When you implement an operator, its compound operator works also.

Operator overloading allows you to implement types that behave like the built-in types when using operators. Be sure to use operators in a way that is natural and understandable for the type.

Syntax for implementing operators is much like a static method, but includes the operator keyword and the operator symbol in place of an identifier.

Additionally, there are rules, such as maintaining symmetry,for using operators, which encourage construction of robust types. I invite you to return for Lesson Skip to content C Station. NET Tutorial Lesson The SqlConnection Object Lesson The SqlCommand Object Lesson Reading Data with the SqlDataReader Lesson Working with Disconnected Data — The DataSet and SqlDataAdapter Lesson Adding Parameters to Commands Lesson Using Stored Procedures C Tutorial Lesson 1: Getting Started with C Lesson 2: Operators, Types, and Variables Lesson 3: Control Statements — Selection Lesson 4: Control Statements — Loops Lesson 5: Introduction to Classes Lesson 8: Class Inheritance Lesson 9: Introduction to Delegates and Events Lesson Introduction to Exception Handling Lesson Using Attributes Lesson Overloading Operators Lesson Introduction to Generic Collections Lesson Anonymous Methods Lesson Topics on C Type Lesson Working with Nullable Types LINQ Tutorial Lesson Introduction to LINQ Lesson Forming Projections Articles Links ASP.

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