What are operators in Dart programming?
Operators are special symbols that perform operations on operands. It is used in an expression. An expression consists of operands (called data) and an operator which evaluates to a value.
In Dart, there are a number of built-in operators that may be used to perform various tasks.
Types of operators
- Arithmetic Operators
- Assignment Operators
- Relational Operators
- Logical Operators
- Conditional Operators
- Type Test Operators
- Bitwise Operators
- Cascade Notation Operators
Arithmetic operators
This class of operators includes:
Operators | Description |
+ | Add (a + b) |
- | Subtract (a - b) |
-expr | Unary Minus ( use to reverse the sign of the expression) |
* | Multiply (a * b) |
/ | Divide (a / b) |
~/ | Divides but return an integer result |
% | Modulus ( outputs remainder of two operands) |
++ | Increment |
-- | Decrement |
void main(){int x = 14;int y = 5;// Using ~/ to divide x and yvar z = x ~/ y;print("Quotient of x and y: $z");// Remainder of a and bvar d = x % y;print("Remainder of x and y: $d");}
Assignment operators
These operators are used to assign value to operands.
Operators | Description |
= | Equal to ( assign values to the expression) |
??= | Assignment operator ( assign the value only if it is null ) |
void main(){int x = 14;int y = 5;// Assigning value to variable zvar z = x / y;print(z);// Assigning value to variable ivar i; //i has a null valuei ??= x * y; // Value is assign to i as it is nullprint(i);// reassign value to ii ??= x + y; // Value is not assign because i is not nullprint(i);}
Relational operators
These operators perform relational operations on operands, which include:
Operators | Description |
> | Greater than (a > b) |
< | Less than (a < b) |
>= | Greater than or equal to (a >= b) |
<= | Less than or equal to (a <= b) |
== | Equal to (a == b) |
!= | Not equal to (a != b) |
void main(){int x = 14;int y = 4;// Greater between x and yvar z = x > y;print("x is greater than y is $z");// Equality between x and yvar d = x == y;print("x and y are equal is $d");}
Logical operators
These operators are used to combine two or more conditions. A Boolean value is returned by logical operators.
Operators used include:
Operators | Description |
&& | And operator ( returns true if both conditions are true) |
|| | Or operator ( returns true if one of the conditions is true) |
! | Not Operator ( reverse the output) |
void main(){int x = 14;int y = 5;// Using And Operatorbool z = x > 5 && y == 5;print(z);// Using Or Operatorbool i = x < 20 || y > 15;print(i);// Using Not Operatorbool d = !(x > 5);print(d);}
Conditional operators
These operators perform a comparison on the operands. The operators include:
Operators | Description |
condition? expr1: expr2 | If the condition is true then expr1 is executed else expr2 |
expr1?? expr2 | If expr1 is non-null return its value else return expr2 value |
void main(){int x = 5;int y = 7;// Conditional Statementvar z = (x * y > 30) ? "First expression is printed" : "Second expression is printed";print(z);}
Type test operators
These operators are used to perform operand comparisons and are useful for checking types at the runtime of a program. Such operators include:
Operators | Description |
is | is (output a Boolean value true if the object has its specific type) |
is! | is not (output a Boolean value false if the object has its specific type) |
void main() {// Type Test OperatorString e = 'Operators in Dart';// Using is to compareprint(e is String);}
Bitwise operators
These operators perform bitwise operations on the operands. Below are the operators used:
Operators | Description |
& | Bitwise And (a & b) returns a one in each bit position where both operands' corresponding bits are ones. |
| | Bitwise And (a | b) returns a one for each bit position where the matching bits of either or both operands are ones. |
^ | Bitwise XOR (a ^ b) returns a one in each bit location when the corresponding bits of either but not both operands are ones. |
~ | Bitwise NOT( ~a) inverts the operand's bits. |
<< | Left shift (a << b) Shifts a in binary representation b (< 32) bits to the left, shifting in zeroes from the right. |
>> | Right shift (a >> b) shifts a in binary representation b (< 32) bits to the right, eliminating bits shifted off. |
void main() {int c = 6;// Bitwise operatorvar bitwise_res = ~ c;print("Bitwise result: $bitwise_res" );}
Cascade notation operators
These operators allow you to perform a sequence of operations on the same element and also perform multiple methods on the same object.
Operator | Description |
.. | Cascading method (performs multiple methods on the same object) |
class EducativeShot {var title;var id;var date;void set(x, y, z){this.title = x;this.id = y;this.date = z;}void shot(){var myShot = this.title + this.id + this.date;print(myShot);}}void main(){// Creating objects of class EducativeShotEducativeShot shot1 = new EducativeShot();EducativeShot shot2 = new EducativeShot();// Without using Cascade Notationshot1.set('Operators', ' 0017820', ' 15.10.2021');shot1.shot();// Using Cascade Notationshot2..set('Operators in Dart programming', ' 0017820', ' 15.10.2021')..shot();}
