Swift 2.0 Syntax Dictionary

: Playground-noun:a place where people can play

Import UIKit

/*:

Dictionary

* and OC difference

* 1. {} replaced by []

* 2. Remove All @

* variable dictionary var

* immutable dictionary let

*/

var dict = ["name": "Lnj", "Age":

Let dict2: [String : nsobject] = ["name": "Lnj", "Age": 30< c28>]

Anyobject = = NSObject

Let dict3: Dictionary<String, anyobject> = ["name": "Lnj", "Age":

Note : in Enterprise Development , the most frequently used dictionary type is [String:anyobject]

Let dict4 = [String: anyobject] ()

Take value

Dict["name"]

Update

If you assign a value to an existing key , It is the update

Dict["name"] = "Zs"

Dict

Increase

If you assign a value to a nonexistent key , It is added

Dict["score"] = 99.9

Dict

Delete

Dict. Removevalueforkey("name")

Dict

Traverse

For key in dict. Keys

{

Print(dict[key])

}

The key in the dictionary is assigned to K, and the value in the dictionary is assigned to v

Note : K and v write casually , but note that key must be assigned to the previous traversal , value must be assigned to the back of a traversal

for (key, value) in dict

{

print(key)

print(value)

}

Swift 2.0 Syntax Dictionary