分类： C/C++
2009-12-21 14:41:50
| Precedence | Operator | Description | Example | Associativity |
|---|---|---|---|---|
| 1一元运算符 | () [] -> . :: ++ -- |
Grouping operator Array access Member access from a pointer Member access from an object Scoping operator Post-increment Post-decrement |
(a + b) / 4; array[4] = 2; ptr->age = 34; obj.age = 34; Class::age = 2; for( i = 0; i < 10; i++ ) ... for( i = 10; i > 0; i-- ) ... |
left to right |
| 2一元运算符 | ! ~ ++ -- - + * & (type) |
Logical negation Bitwise complement Pre-increment Pre-decrement Unary minus Unary plus Dereference Address of Cast to a given type Return size in bytes |
if( !done ) ... flags = ~flags; for( i = 0; i < 10; ++i ) ... for( i = 10; i > 0; --i ) ... int i = -1; int i = +1; data = *ptr; address = &obj; int i = (int) floatNum; int size = sizeof(floatNum); |
right to left |
| 3成员运算符 | ->* .* |
Member pointer selector Member pointer selector |
ptr->*var = 24; obj.*var = 24; |
left to right |
| 4算术运算符 | * / % |
Multiplication Division Modulus |
int i = 2 * 4; float f = 10 / 3; int rem = 4 % 3; |
left to right |
| 5算术运算符 | + - |
Addition Subtraction |
int i = 2 + 3; int i = 5 - 1; |
left to right |
| 6位移运算符 | << >> |
Bitwise shift left Bitwise shift right |
int flags = 33 << 1; int flags = 33 >> 1; |
left to right |
| 7比较运算符 | < <= > >= |
Comparison less-than Comparison less-than-or-equal-to Comparison greater-than Comparison geater-than-or-equal-to |
if( i < 42 ) ... if( i <= 42 ) ... if( i > 42 ) ... if( i >= 42 ) ... |
left to right |
| 8比较运算符 | == != |
Comparison equal-to Comparison not-equal-to |
if( i == 42 ) ... if( i != 42 ) ... |
left to right |
| 9位运算符 | & | Bitwise AND | flags = flags & 42; | left to right |
| 10位运算符 | ^ | Bitwise exclusive OR | flags = flags ^ 42; | left to right |
| 11位运算符 | | | Bitwise inclusive (normal) OR | flags = flags | 42; | left to right |
| 12位运算符 | && | Logical AND | if( conditionA && conditionB ) ... | left to right |
| 13逻辑运算符 | || | Logical OR | if( conditionA || conditionB ) ... | left to right |
| 14三元运算符 | ? : | Ternary conditional (if-then-else) | int i = (a > b) ? a : b; | right to left |
| 15赋值运算符 | = += -= *= /= %= &= ^= |= <<= >>= |
Assignment operator Increment and assign Decrement and assign Multiply and assign Divide and assign Modulo and assign Bitwise AND and assign Bitwise exclusive OR and assign Bitwise inclusive (normal) OR and assign Bitwise shift left and assign Bitwise shift right and assign |
int a = b; a += 3; b -= 4; a *= 5; a /= 2; a %= 3; flags &= new_flags; flags ^= new_flags; flags |= new_flags; flags <<= 2; flags >>= 2; |
right to left |
| 16逗号运算符 | , | Sequential evaluation operator | for( i = 0, j = 0; i < 10; i++, j++ ) ... | left to right |
