07_Type_conversion.md

Type Conversion

Type conversion means converting a data type into another data type. But there are two kinds of type conversion in JavaScript.

1. Explicit Type Conversion
2. Implicit Type Conversion

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Explicit Type Conversion

In this type conversion, the type of data will be changed manually by a developer which is known as explicit type conversion.

There are 3 types of conversion methods in JS:

1. String()
2. Number()
3. Boolean()

// Number to String Conversion
let numToStr = 46;
console.log(typeof numToStr, numToStr); //number 46

numToStr = String(numToStr);
console.log(typeof numToStr, numToStr); //string 46

// String to Boolean Conversion
let strToBool = "";
console.log(typeof strToBool, strToBool); //string

strToBool = Boolean(strToBool);
console.log(typeof strToBool, strToBool); //boolean false

strToBool = "false";
console.log(typeof strToBool, strToBool); //string false

strToBool = Boolean(strToBool);
console.log(typeof strToBool, strToBool); //boolean true

// Null to Number Conversion
let nullToNum = null;
console.log(typeof nullToNum, nullToNum); //object null

nullToNum = Number(nullToNum);
console.log(typeof nullToNum, nullToNum); //number 0

// String to Number Conversion
let strToNum = "";
console.log(typeof strToNum, strToNum); //string

strToNum = Number(strToNum);
console.log(typeof strToNum, strToNum); //number 0

strToNum = "Ajay";
console.log(typeof strToNum, strToNum); //string Ajay

strToNum = Number(strToNum);
console.log(typeof strToNum, strToNum); //number NaN

Implicit Type Conversion

In this type conversion, the JavaScript engine automatically converts data from one type to another type which is known as implicit type conversion.

Implicit type conversion is also known as type coercion in JavaScript.

// Type Coercion
console.log(564 + "Ajay"); //"564Ajay"
console.log(543 + "55"); //"54355"
console.log(50 - "55"); //-5
console.log(50 / "10"); //5
console.log("50" / "10"); //5