Basics of Kotlin

Written by: developervsandhu

Technology and Gadgets

Basics of Kotlin

Module 2: Basics of Kotlin

Variables and Data Types

• Kotlin variables refer to memory location to store data
• It is container which holds values
• data of the variables can be changes and reused in program

var name = "Learn Code With Durgesh"
val action = "Subscribe"

val vs. var

• var type variabels are mutable can be changed

  var name="Learn Code With Durgesh"
  name="Follow "//Success

• val types of variables are immutable cannot be changed

 val name="Learn Code With Durgesh"
 name="Follow "//Error

Data Types

-Data types represent the type of data variabels holds.

• Number

  Hold any type of numeric values. Numbers can be of two types

  • Integers(Byte-1bytes, Short-2Bytes, Int-4Bytes ,Long-8Bytes)
  • Floating Point(Float-4Bytes, Double-8Bytes)

• Character

  In kotlin char represented by Char keywords 2Bytes

• Boolean

  true/false - 1bit

• Array

  Represendted by Kotlin Array class and can be created using function arrayOf() and Array() constructor.

• String

  In Kotlin String is represented by String class.

  Set of character is a string.

  "This is simple string"

  """ This is raw string """

Type inference

When be create and assign variables instantly the there is not need to provide the type type is infered by compiler.

  val name = "Durges sir"

Type Conversion

There are helper functions that helps us to convert one type value into another type

toByte()
toShort()
toInt()
toLong()
toFloat()
toDouble()
toChar()

Example

var value1=50
var value2:Long=value1.toLong()

• Basic Operators

• Arithmetic operators

  +, -, *, /, %

• Comparison operators

  , <, >=, <=, !=, ==

• Logical operators

  &&, ||, !

• Input/Output

  • readln() and readLine() functions is used to take inpout

  • print() and println() functions are used to print on console