Operators in Dart

Operators In Dart

Operators are used to perform mathematical and logical operations on the variables. Each operation in dart uses a symbol called the operator to denote the type of operation it performs. Before learning operators in the dart, you must understand the following things.

  • Operands : It represents the data.
  • Operator It represents how the operands will be processed to produce a value.
Info

Note: Suppose the given expression is 2 + 3. Here 2 and 3 are operands, and + is the operator.

Types Of Operators

  • Arithmetic Operators
  • Increment and Decrement Operators
  • Assignment Operators
  • Logical Operators
  • Type Test Operators

Arithmetic Operators

Arithmetic operators are the most common types of operators. They perform operations like addition, subtraction, multiplication, division, etc.

Operator Symbol Operator Name Description
+ Addition For adding two operands
- Subtraction For subtracting two operands
-expr Unary Minus For reversing the sign of the expression
* Multiplication For multiplying two operands
/ Division For dividing two operands and give output in double
~/ Division For dividing two operands and give output in integer
% Modulus Remainder After Integer Division
++ Increment Increase Value By 1. For E.g a++;
-- Decrement Decrease Value By 1. For E.g a–;

Let’s look at how to perform arithmetic calculations in dart.

void main() {
 // declaring two numbers 
 int num1=10;
 int num2=3;
 
 // performing arithmatic calulation 
 int sum=num1+num2;       // addition
 int diff=num1-num2;      // subtraction
 int unaryMinus = -num1;    // unary minus  
 int mul=num1*num2;       // multiplication
 double div=num1/num2;    // division
 int div2 =num1~/num2;     // integer division
 int mod=num1%num2;       // show remainder
 
//Printing info 
 print("The addition is $sum.");
 print("The subtraction is $diff.");
 print("The unary minus is $unaryMinus.");
 print("The multiplication is $mul.");
 print("The division is $div.");
 print("The integer division is $div2.");
 print("The modulus is $mod."); 
}

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Increment and Decrement Operators

With increment and decrement operators, you can increase and decrease values. If ++ is used at the beginning, then it is a prefix. If it is used at last, then it is postfix.

Operator Symbol Operator Name Description
++var Pre Increment Increase Value By 1. var = var + 1 Expression value is var+1
--var Pre Decrement Decrease Value By 1. var = var - 1 Expression value is var-1
var++ Post Increment Increase Value By 1. var = var + 1 Expression value is var
var-- Post Decrement Decrease Value By 1. var = var - 1 Expression value is var
Info

Note: ++var increases the value of operands, whereas var++ return the actual value of operands before the increment.

void main() {
// declaring two numbers 
 int num1=0;
 int num2=0;
 
// performing increment / decrement operator  

// pre increment   
num2 = ++num1;
print("The value of num2 is $num2");

// reset value to 0 
num1 = 0;
num2 = 0;

// post increment  
num2 =  num1++;
print("The value of num2 is $num2");  
  
}

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Assignment Operators

It is used to assign some values to variables. Here, we are assigning 24 to the age variable.

int age = 24;
Operator Type Description
= Assign a value to a variable
+= Adds a value to a variable
-= Reduces a value to a variable
*= Multiply value to a variable
/= Divided value by a variable 
void main() {
  double age = 24;
  age+= 1;  // Here age+=1 means age = age + 1.
  print("After Addition Age is $age");
  age-= 1;  //Here age-=1 means age = age - 1.
  print("After Aubtraction Age is $age");
  age*= 2;  //Here age*=2 means age = age * 2.
  print("After Multiplication Age is $age");
  age/= 2;  //Here age/=2 means age = age / 2.
  print("After Division Age is $age");
}

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Info

Note: To assign only if the assign-to variable is null use ?? operator.

Relational Operators

Relational operators are also called comparison operators. They are used to make a comparison.

Operator Symbol Operator Name Description
> Greater than Used to check which operand is bigger and gives result as boolean
< Less than Used to check which operand is smaller and gives result as boolean
>= Greater than or equal to Used to check which operand is bigger or equal and gives result as boolean
<= Less than or equal to Used to check which operand is smaller or equal and gives result as boolean
== Equal to Used to check operands are equal to each other and gives result as boolean
!= Not equal to Used to check operand are not equal to each other and gives result as boolean 
void main() {
  
 int num1=10;
 int num2=5;
 //printing info
 print(num1==num2); 
 print(num1<num2);
 print(num1>num2);
 print(num1<=num2);
 print(num1>=num2);
}

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Logical Operators

It is used to compare values.

Operator Type Description
&& This is ‘and’, return true if all conditions are true
|| This is ‘or’. Return true if one of the conditions is true
! This is ’not’. return false if the result is true and vice versa 
void main(){
  int userid = 123;
    int userpin = 456;

    // Printing Info
    print((userid == 123) && (userpin== 456)); // print true
    print((userid == 1213) && (userpin== 456)); // print false.
    print((userid == 123) || (userpin== 456)); // print true.
    print((userid == 1213) || (userpin== 456)); // print true
    print((userid == 123) != (userpin== 456));//print false

}
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Type Test Operators

In dart, type test operators are useful for checking types at runtime.

Operator Symbol Operator Name Description
is is Gives boolean value true if the object has a specific type
is! is not Gives boolean value false if the object has a specific type 
void main() {
  String value1 = "Dart Tutorial";
  int age = 10;
  
  print(value1 is String);
  print(age is !int);
}

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Video

Watch our video on the operators in Dart.