Go Basics - arrays and slices

The same thing ：

1) Only one set of data structures of the same type can be stored

2) Are accessed through subscripts , And have capacity length , The length passes through len obtain , Capacity pass cap obtain

difference ：

1） Array is fixed length , Access and copy cannot exceed the length of the array definition , Otherwise the subscript will cross the line , Slice length and capacity can be automatically expanded

2） Arrays are value types , Slicing is a reference type , Each slice references an underlying array , The slice itself cannot store any data , The underlying array stores data , So when you modify the slice, you modify the data in the underlying array . Once the slice is expanded , Point to a new underlying array , The memory address changes accordingly

Succinct answer ：

1） Defined differently 2） Different initialization methods , Array needs to specify size , The size does not change 3） In function passing , Array slices are value passing .

Definition of array

var a1 [3]int

var a2 [...]int{1,2,3}

Definition of slice

var a1 []int

var a2 :=make([]int,3,5)

Initialization of an array

a1 := [...]int{1,2,3}

a2 := [5]int{1,2,3}

Initialization of slices

b:= make([]int,3,5)