Objective-C language has the following operators.
Arithmetic Operators
Relational Operators
Logical Operators
Bitwise Operators
Assignment Operators
Misc Operators
The following table shows all the arithmetic operators in Objective-C.
| Operator | Description |
|---|---|
| + | Adds two operands |
| - | Subtracts second operand from the first |
| * | Multiplies both operands |
| / | Divides numerator by denominator |
| % | Modulus Operator and remainder of after an integer division |
| ++ | Increment operator increases integer value by one |
| -- | Decrement operator decreases integer value by one |
The following table lists the relational operators supported by Objective-C.
| Operator | Description |
|---|---|
| == | Checks if the values of two operands are equal or not. |
| != | Checks if the values of two operands are not equal. |
| > | Checks if the value of left operand is greater than the value of right operand. |
| < | Checks if the value of left operand is less than the value of right operand. |
| >= | Checks if the value of left operand is greater than or equal to the value of right operand. |
| <= | Checks if the value of left operand is less than or equal to the value of right operand. |
The following table lists the logical operators supported by Objective-C language.
| Operator | Description |
|---|---|
| && | Logical AND operator. If both the operands are non zero then condition becomes true. |
| || | Logical OR Operator. If any of the two operands is non zero then condition becomes true. |
| ! | Logical NOT Operator. Reverse the logical state of its operand. If a condition is true, then Logical NOT operator will make false. |
Bitwise operator works on bits and perform bit by bit operation.
The truth tables for &, |, and ^ are as follows:
| p | q | p & q | p | q | p ^ q |
|---|---|---|---|---|
| 0 | 0 | 0 | 0 | 0 |
| 0 | 1 | 0 | 1 | 1 |
| 1 | 1 | 1 | 1 | 0 |
| 1 | 0 | 0 | 1 | 1 |
The Bitwise operators supported by Objective-C language are listed in the following table.
| Operator | Description |
|---|---|
| & | Binary AND Operator copies a bit to the result if it exists in both operands. |
| | | Binary OR Operator copies a bit if it exists in either operand. |
| ^ | Binary XOR Operator copies the bit if it is set in one operand but not both. |
| ~ | Binary Ones Complement Operator is unary and has the effect of 'flipping' bits. |
| << | Binary Left Shift Operator. The left operands value is moved left by the number of bits specified by the right operand. |
| >> | Binary Right Shift Operator. The left operands value is moved right by the number of bits specified by the right operand. |
There are following assignment operators supported by Objective-C language:
| Operator | Description |
|---|---|
| = | Assignment operator, Assigns values from right side operands to left side operand |
| += | Add AND assignment operator, It adds right operand to the left operand and assigns the result to left operand |
| -= | Subtract AND assignment operator, It subtracts right operand from the left operand and assigns the result to left operand |
| *= | Multiply AND assignment operator, It multiplies right operand with the left operand and assigns the result to left operand |
| /= | Divide AND assignment operator, It divides left operand with the right operand and assigns the result to left operand |
| %= | Modulus AND assignment operator, It takes modulus using two operands and assigns the result to left operand |
| <<= | Left shift AND assignment operator |
| >>= | Right shift AND assignment operator |
| &= | Bitwise AND assignment operator |
| ^= | bitwise exclusive OR and assignment operator |
| |= | bitwise inclusive OR and assignment operator |
sizeof() returns the size of an variable. sizeof(anInteger) will return 4.
value = condition ? X:Y is called the Conditional Expression.
If Condition is true ? Then assign X to value, Otherwise assign Y to value.
Conditional operator ? : can be used to replace if...else statements.
It has the following general form:
Exp1 ? Exp2 : Exp3;
Where Exp1, Exp2, and Exp3 are expressions. Notice the use and placement of the colon.
The value of a ? expression is determined like this: Exp1 is evaluated. If it is true, then Exp2 is evaluated and becomes the value of the entire ? expression. If Exp1 is false, then Exp3 is evaluated and its value becomes the value of the expression.
& returns the address of an variable.
&a; will give actual address of the variable.
* is the Pointer operator to a variable.
*a; will pointer to a variable.