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C# Operators

C# provides a large set of operators, which are symbols that specify which operations to perform in an expression. Operations on integral types such as ==, !=, <, >, <=, >=, binary +, binary -, ^, &, |, ~, ++, --, and sizeof() are generally allowed on enumerations. In addition, many operators can be overloaded by the user, thus changing their meaning when applied to a user-defined type.

The following table lists the C# operators grouped in order of precedence. Operators within each group have equal precedence.

Operator category

Operators

Primary

x.y

f(x)

a[x]

x++

x--

new

typeof

checked

unchecked

default(T)

delegate

->

Unary

+

-

!

~

++x

--x

(T)x

true

false

&

sizeof

Multiplicative

*

/

%

Additive

+

-

Shift

<<

>>

Relational and type testing

<

>

<=

>=

is

as

Equality

==

!=

Logical AND

&

Logical XOR

^

Logical OR

|

Conditional AND

&&

Conditional OR

||

Null-coalescing

??

Conditional

?:

Assignment and lambda expression

=

+=

-=

*=

/=

%=

&=

|=

^=

<<=

>>=

=> Lambda Operator

Arithmetic Overflow

The arithmetic operators (+, -, *, /) can produce results that are outside the range of possible values for the numeric type involved. You should refer to the section on a particular operator for details, but in general:

  • Integer arithmetic overflow either throws an OverflowException or discards the most significant bits of the result. Integer division by zero always throws a DivideByZeroException.

  • Floating-point arithmetic overflow or division by zero never throws an exception, because floating-point types are based on IEEE 754 and so have provisions for representing infinity and NaN (Not a Number).

  • Decimal arithmetic overflow always throws an OverflowException. Decimal division by zero always throws a DivideByZeroException.

When integer overflow occurs, what happens depends on the execution context, which can be checked or unchecked. In a checked context, an OverflowException is thrown. In an unchecked context, the most significant bits of the result are discarded and execution continues. Thus, C# gives you the choice of handling or ignoring overflow.

In addition to the arithmetic operators, integral-type to integral-type casts can cause overflow, for example, casting a long to an int, and are subject to checked or unchecked execution. However, bitwise operators and shift operators never cause overflow.

See Also

Reference

Overloadable Operators (C# Programming Guide)

C# Keywords

Concepts

C# Programming Guide

Other Resources

C# Reference

Visual C#