You can redefine or overload operators built in C#. Therefore, programmers can also use user-defined types of operators. Overload operators are functions with special names defined by the keyword operator followed by the operator symbol. Like other functions, overload operators have return types and parameter lists.
For example, see the following function:
public static Box operator+ (Box b, Box c)
{
Box box = new Box();
= + ;
= + ;
= + ;
return box;
}
The above function implements the addition operator (+) for the user-defined class Box. It adds the properties of two Box objects and returns the added Box object.
Implementation of operator overloading
The following program demonstrates the complete implementation:
using System;
namespace OperatorOvlApplication
{
class Box
{
private double length; // length private double breadth; // Width private double height; // high
public double getVolume()
{
return length * breadth * height;
}
public void setLength( double len )
{
length = len;
}
public void setBreadth( double bre )
{
breadth = bre;
}
public void setHeight( double hei )
{
height = hei;
}
// Overload the + operator to add two Box objects public static Box operator+ (Box b, Box c)
{
Box box = new Box();
= + ;
= + ;
= + ;
return box;
}
}
class Tester
{
static void Main(string[] args)
{
Box Box1 = new Box(); // Declare Box1, type Box Box Box2 = new Box(); // Declare Box2, type Box Box Box3 = new Box(); // Declare Box3, type Box double volume = 0.0; // Volume
// Box1 details (6.0);
(7.0);
(5.0);
// Box2 details (12.0);
(13.0);
(10.0);
// The volume of Box1 volume = ();
("Box1 Volume of： {0}", volume);
// The volume of Box2 volume = ();
("Box2 Volume of： {0}", volume);
// Add two objects together Box3 = Box1 + Box2;
// The volume of Box3 volume = ();
("Box3 Volume of： {0}", volume);
();
}
}
}
When the above code is compiled and executed, it produces the following results:
Box1's volume: 210
Box2's volume: 1560
Box3's volume: 5400
Overloadable and non-overloadable operators
The following table describes the ability of operator overloading in C#:
| Operators | describe |
| +, -, !, ~, ++, -- | These unary operators have only one operand and can be overloaded. |
| +, -, *, /, % | These binary operators have two operands and can be overloaded. |
| ==, !=, <, >, <=, >= | These comparison operators can be overloaded. |
| &&, || | These conditional logic operators cannot be directly overloaded. |
| +=, -=, *=, /=, %= | These assignment operators cannot be overloaded. |
| =, ., ?:, ->, new, is, sizeof, typeof | These operators cannot be overloaded. |
Example
For the above discussion, let's extend the above example and overload more operators:
using System;
namespace OperatorOvlApplication
{
class Box
{
private double length; // length private double breadth; // Width private double height; // high
public double getVolume()
{
return length * breadth * height;
}
public void setLength( double len )
{
length = len;
}
public void setBreadth( double bre )
{
breadth = bre;
}
public void setHeight( double hei )
{
height = hei;
}
// Overload the + operator to add two Box objects public static Box operator+ (Box b, Box c)
{
Box box = new Box();
= + ;
= + ;
= + ;
return box;
}
public static bool operator == (Box lhs, Box rhs)
{
bool status = false;
if ( == && ==
&& == )
{
status = true;
}
return status;
}
public static bool operator !=(Box lhs, Box rhs)
{
bool status = false;
if ( != || !=
|| != )
{
status = true;
}
return status;
}
public static bool operator <(Box lhs, Box rhs)
{
bool status = false;
if ( < &&
< && < )
{
status = true;
}
return status;
}
public static bool operator >(Box lhs, Box rhs)
{
bool status = false;
if ( > &&
> && > )
{
status = true;
}
return status;
}
public static bool operator <=(Box lhs, Box rhs)
{
bool status = false;
if ( <= &&
<= && <= )
{
status = true;
}
return status;
}
public static bool operator >=(Box lhs, Box rhs)
{
bool status = false;
if ( >= &&
>= && >= )
{
status = true;
}
return status;
}
public override string ToString()
{
return ("({0}, {1}, {2})", length, breadth, height);
}
}
class Tester
{
static void Main(string[] args)
{
Box Box1 = new Box(); // Declare Box1, type Box Box Box2 = new Box(); // Declare Box2, type Box Box Box3 = new Box(); // Declare Box3, type Box Box Box4 = new Box();
double volume = 0.0; // Volume
// Box1 details (6.0);
(7.0);
(5.0);
// Box2 details (12.0);
(13.0);
(10.0);
// Use overloaded ToString() to display two boxes ("Box1： {0}", ());
("Box2： {0}", ());
// The volume of Box1 volume = ();
("Box1 Volume of： {0}", volume);
// The volume of Box2 volume = ();
("Box2 Volume of： {0}", volume);
// Add two objects together Box3 = Box1 + Box2;
("Box3： {0}", ());
// The volume of Box3 volume = ();
("Box3 Volume of： {0}", volume);
//comparing the boxes
if (Box1 > Box2)
("Box1 is greater than Box2");
else
("Box1 is no greater than Box2");
if (Box1 < Box2)
("Box1 is less than Box2");
else
("Box1 is not less than Box2");
if (Box1 >= Box2)
("Box1 is greater than or equal to Box2");
else
("Box1 is not greater than or equal to Box2");
if (Box1 <= Box2)
("Box1 is less than or equal to Box2");
else
("Box1 is not less than or equal to Box2");
if (Box1 != Box2)
("Box1 does not equal Box2");
else
("Box1 equals Box2");
Box4 = Box3;
if (Box3 == Box4)
("Box3 equals Box4");
else
("Box3 does not equal Box4");
();
}
}
}
When the above code is compiled and executed, it produces the following results:
Box1： (6, 7, 5)
Box2： (12, 13, 10)
Box1's volume: 210
Box2's volume: 1560
Box3： (18, 20, 15)
Box3's volume: 5400
Box1 is no greater than Box2
Box1 is less than Box2
Box1 is not greater than or equal to Box2
Box1 is less than or equal to Box2
Box1 does not equal Box2
Box3 equals Box4
The above is the detailed content of the detailed analysis of the overload of c# operators. For more information about the overload of c# operators, please pay attention to my other related articles!