Not-equal-value or Not-equal-type Operator in JavaScript



Comparison Not-equal-value or Not-equal-type

Comparison not-equal-value or not-equal-type operator takes two operands, returns true if left and right operands are not equal in value or not equal in data type, or false otherwise.

Syntax

!== symbol is used for comparison not-equal-value or not-equal-type operator.

a !== 5  //returns true if a is not 5 or not numeric
a !== b

Since not-equal-value and not-equal-type operator does check either type or value, the following example illustrates the case.

a = 5     //a has a value of 5 (numeric)
a !== '5' //returns true
a !== 4   //returns true
a !== 5   //returns false

Examples

1. In the following program, we check if value in a is not equal to 5, or a is not numeric.

var a = 5;
if (a !== 5) {
    console.log('a is not 5 or not numeric');
} else {
    console.log('a is either 5 or numeric');
}

2. In the following program, we will check if values in a and b are not equal to each other either in value or type.

var a = 5;
var b = 7;
if (a !== b) {
    console.log('a and b are not equal');
} else {
    console.log('a and b are equal');
}

3. In the following program, we check if value in a is not equal to 5 in value, or not numeric.

var a = '5';
if (a !== 5) {
    console.log('a is not 5 or not numeric');
} else {
    console.log('a is either 5 or numeric');
}

The variable a is assigned with a string type value. Since comparison not-equal-value and not-equal-type operator checks both the type and value, a !== 5 returns true.