TypeScript Number

TypeScript, similar to JavaScript, supports the Number object.

The Number object is a wrapper object for primitive numeric values.

Syntax

var num = new Number(value);

Note: If a parameter value cannot be converted to a number, it returns NaN (Not-a-Number).

Number Object Properties

The following table lists the properties supported by the Number object:

No.	Property & Description
1.	MAX_VALUE The largest number that can be represented. The MAX_VALUE property is close to 1.79E+308. Values greater than MAX_VALUE are represented as "Infinity".
2.	MIN_VALUE The smallest number that can be represented, the closest positive number to zero (which will not actually become zero). The largest negative number is -MIN_VALUE. The value of MIN_VALUE is approximately 5e-324. Values smaller than MIN_VALUE ("underflow values") are converted to 0.
3.	NaN Not-a-Number value.
4.	NEGATIVE_INFINITY Negative infinity, returned on overflow. This value is less than MIN_VALUE.
5.	POSITIVE_INFINITY Positive infinity, returned on overflow. This value is greater than MAX_VALUE.
6.	prototype A static property of the Number object. Allows you to add properties and methods to the object.
7.	constructor Returns a reference to the Number function that created the object.

TypeScript

console.log("TypeScript Number Properties: "); 
console.log("Maximum value: " + Number.MAX_VALUE); 
console.log("Minimum value: " + Number.MIN_VALUE); 
console.log("Negative infinity: " + Number.NEGATIVE_INFINITY); 
console.log("Positive infinity: " + Number.POSITIVE_INFINITY);

Compiling the above code generates the following JavaScript code:

JavaScript

console.log("TypeScript Number Properties: ");
console.log("Maximum value: " + Number.MAX_VALUE);
console.log("Minimum value: " + Number.MIN_VALUE);
console.log("Negative infinity: " + Number.NEGATIVE_INFINITY);
console.log("Positive infinity: " + Number.POSITIVE_INFINITY);

Output:

TypeScript Number Properties:
Maximum value: 1.7976931348623157e+308
Minimum value: 5e-324
Negative infinity: -Infinity
Positive infinity: Infinity

NaN Example

TypeScript

var month = 0 
if( month<=0 || month >12) { 
    month = Number.NaN 
    console.log("Month is: " + month) 
} else { 
    console.log("Correct month value entered.") 
}

Compiling the above code generates the following JavaScript code:

JavaScript

var month = 0;
if (month <= 0 || month > 12) {
    month = Number.NaN;
    console.log("Month is: " + month);
}
else {
    console.log("Correct month value entered.");
}

Output:

Month is: NaN

prototype Example

TypeScript

function employee(id:number, name:string) { 
    this.id = id 
    this.name = name 
} 

var emp = new employee(123, "admin") 
employee.prototype.email = "[email protected]" 

console.log("Employee ID: " + emp.id) 
console.log("Employee Name: " + emp.name) 
console.log("Employee Email: " + emp.email)

Compiling the above code generates the following JavaScript code:

JavaScript

function employee(id, name) {
    this.id = id;
    this.name = name;
}
var emp = new employee(123, "admin");
employee.prototype.email = "[email protected]";
console.log("Employee ID: " + emp.id);
console.log("Employee Name: " + emp.name);
console.log("Employee Email: " + emp.email);

Output:

Employee ID: 123
Employee Name: admin
Employee Email: [email protected]

Number Object Methods

The Number object supports the following methods:

No.	Method & Description	Example
1.	toExponential() Converts the value of the object to exponential notation.	// toExponential() <br>var num1 = 1225.30 <br>var val = num1.toExponential(); <br>console.log(val) // Output: 1.2253e+3
2.	toFixed() Converts a number to a string, rounding to a specified number of decimals.	var num3 = 177.234 <br>console.log("num3.toFixed() is " + num3.toFixed()) // Output: 177<br>console.log("num3.toFixed(2) is " + num3.toFixed(2)) // Output: 177.23<br>console.log("num3.toFixed(6) is " + num3.toFixed(6)) // Output: 177.234000
3.	toLocaleString() Converts a number to a string, using local number formatting.	var num = new Number(177.1234); <br>console.log(num.toLocaleString()); // Output: 177.1234
4.	toPrecision() Formats a number to a specified length.	var num = new Number(7.123456); <br>console.log(num.toPrecision()); // Output: 7.123456 <br>console.log(num.toPrecision(1)); // Output: 7<br>console.log(num.toPrecision(2)); // Output: 7.1
5.	toString() Converts a number to a string, using the specified base. The base is an integer between 2 and 36. If omitted, base 10 is used.	var num = new Number(10); <br>console.log(num.toString()); // Output in base 10: 10<br>console.log(num.toString(2)); // Output in base 2: 1010<br>console.log(num.toString(8)); // Output in base 8: 12
6.	valueOf() Returns the primitive value of a Number object.	var num = new Number(10); <br>console.log(num.valueOf()); // Output: 10

❮ Ts Ambient Ts Operators ❯