The JavaScript Number() constructor is used to create a Number object. When used as a regular function, it converts different data types into numbers if possible.
- Creates a Number object when used with the new keyword.
- Performs type conversion to a number when called as a function.
- Returns NaN if the value cannot be converted to a valid number.
// Using Number() as a constructor
let numObj = new Number(25);
console.log(numObj); // Number {25}
// Using Number() as a function (type conversion)
let a = Number("123");
let b = Number(true);
let c = Number("hello");
console.log(a);
console.log(b);
console.log(c);
Syntax:
Number(object)Parameters: This function accepts a single parameter as mentioned above and described below:
- object: This parameter holds the objects that will be converted to any type of javascript variable to number type.
Return Values: The number() constructor returns the number format for any type of javascript variable.
[Example 1]: We will create a new number using Number Constructor
function func() {
let a = new Number(5);
console.log(a);
}
func();
[Example 2]: We will convert a Number String to Number using Number constructor as a function.
function func() {
// Original string
let a = "10";
let value = Number(a);
console.log(value);
}
func();
[Example 3]: We will convert the date into a number, and the conversion will return the converted date in milliseconds.
function func() {
let value = Number(new Date("2017-09-30"));
console.log(value);
}
func();
[Example 4]: We will convert a Non-Number String to a Number using the Number constructor as a function.
function func() {
let value = Number("John");
console.log(value);
}
func();
