C# Operators
Updated: July 2008
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 | |
Unary | |
Multiplicative | |
Additive | |
Shift | |
Relational and type testing | |
Equality | |
Logical AND | |
Logical XOR | |
Logical OR | |
Conditional AND | |
Conditional OR | |
Conditional | |
Assignment | |
Null-coalescing | |
Lambda |
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.