typescript 02 basic types

typescript type of foundation

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// digital type arithmetic decimal octal 

let  num1:number=2;

let num2:number=2+5;

let num3:number=0x2;

let num4:number=0-2;

let num5:number=0/2;

// string type supports common character string and templates

let gender:string='boy'

let username:string='iwan'

let username2:string=`iwan is good ${gender}`

// Boolean value type

let isTrue:boolean=true;

let isFalse:boolean=false;

// Data type of array type and the type of the array must be of the order of a predetermined association.

// define array types in two ways

let arr: number [] = [1,2,3] // define the element is an array type numbers only

let arr2:Array<number>=[1,2,3]

let any:any[]=[1,'2',2,true,[1,2]]

let any2: Array <any> = [1, '2', 2, true, [1,2]] // define the elements of an array may be any type

// represents a tuple allows the array element number and type of known, not necessarily the same type of elements

let x: [string, number,boolean];

   x = [ 'Iwan', 5, true]