[SWIFT] Let's understand the Array (Element) type!

Now that we've learned about the Array (Element) type, we'll output it.

What is Array (Element) type?

*** Array (Element) type is a type that represents an array in a nutshell. *** ***

For example Array (Element) types can be represented using array literals, such as [1,2,3].


1.let a = [a,b,c]
2.let b = [1,2,3]

It is convenient to use the Array (Element) type. You can update, add, join, and delete *** elements for Array (Element) type values.

Let's dig deep one by one!

Element update


               //0 1 2 
1.var numbers = [1,2,3]
2.numbers[1] = [4] //We are updating the first 2
numbers// [1,4,3]

Add element

*** Use the *** append (_ :) *** method to add an element to the end *** The following example adds a "d" of type [String]


1.let strings  = ["a","b","c"]
2.strings append(d)//["a","b","c","d"]

You can also add it to any *** location. To add an element in any *** location, use the *** insert (_: at: 1) ***, method.

In the following example, nsert (_: at: 1) ***, method is used and "b" is added second.


1.let strings  = ["a","c","d"]
2.strings insert("b",at1)//["a","b","c","d"]

Combine elements

You can combine elements of type Array (Element) with the + operator.


1.let strings1 = ["Ah","I","U"]//[String type]
2.let c =["e","O"]//[String type]

let result = strings1+let c //["Ah","I","U","e","O"]

Delete element

To remove an element, delete anywhere *** remove (at :) ***, remove the last element *** removeLast () ***, removeAll () method to remove all elements Three are prepared.


var strings = ["Ah","I","U","e","O"]

strings//["Ah","I","e","O"]//"U"Is deleted

strings//["Ah","I","e"]//At the end"O"Is deleted


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