// 基本定義
let arr:number[] = [1,2,3];
let arrS: string[] = ["1","2"]

var arr:number[] = new Array(10);  
for(var i = 0; i<arr.length; i++) { 
    arr[i] = i * 2 
    console.log(arr[i]) 
}

let arr1:Array<number> = [1,2,3,4,5]
let arr2:number[] = new Array(1,2,3);
console.log("arr1===="+arr1);
console.log("arr2===="+arr2);

var arr_name:datatype[][]=[ [val1,val2,val3],[v1,v2,v3] ]

var arr:number[][] = [[1,2,3],[4,5,6]]  
console.log(arr[0][0]) 
console.log(arr[0][1]) 
console.log(arr[0][2]) 
console.log(arr[1][0]) 
console.log(arr[1][1]) 
console.log(arr[1][2])

// 聲明多維數(shù)組
let arr:number[][] = [[1,2,3], [4,5,6]];
// 泛型形式聲明多維數(shù)組(聯(lián)合類型)
let arr1:Array<Array<number | string>> = [[1,2,3,"123"],[4,5,6,"789"],[]];
console.log(arr)
console.log(arr1)

// 類數(shù)組
function Arr(... args:any):void{
    console.log(arguments) //類數(shù)組,arguments是參數(shù)
    let arr:IArguments = arguments  //用IArguments去接收
}
Arr(1,2,3)  //[Arguments] { '0': 1, '1': 2, '2': 3 }

// 數(shù)組解構(gòu)
var arr = [12, 13];
var x = arr[0], y = arr[1]; // 將數(shù)組的兩個元素賦值給變量 x 和 y
console.log(x);
console.log(y);

// 通過接口描述數(shù)組
interface NumberArray{
    [index:number]:number;  //只要索引的類型是數(shù)字，那么值的類型也必須是數(shù)字,換成string也是一樣的
}
let arr:NumberArray = [1,2,3];
console.log(arr);

// 數(shù)組迭代
var j:any; 
var nums:number[] = [1,2,3,4] 
for(j in nums) { 
    console.log(nums[j]) 
}