Simple operation of Nsdictionary and Nsset in OC

/**

* Dictionary

data that holds the key-value pair type

storing data is unordered.

*/

dictionary output in console is included with {} .

Nsdictionary Immutable Dictionary

1. Creating Objects

Initialize Method

Nsdictionary *dict1 = [[nsdictionary alloc] initwithobjectsandkeys:@ "Zhizunbao" , @ "name", @ "man", @ "Sex", @27, @ "age", Nil];

NSLog(@ "%@", Dict1);

Nsdictionary *dict2 = [[nsdictionary alloc] initwithobjects:@[@ "Yinhao", @ "Man", @27] forkeys:@[@ "name" @ "Sex" @ "age"] ];

NSLog(@ "%@", dict2);

class Method

Nsdictionary *dict3 = [nsdictionary dictionarywithobjectsandkeys:@ "LeBron" @ "name" @ "Man ", @ "Sex", @31, @ "age", Nil];

NSLog(@ "%@", dict3);

method of literal weight

Nsdictionary *dict4 = @{

@ "Name" : @ "LeBron",

@ "Sex" : @ "man",

@ "Age" : @32,

@ "Hobby" : @ "basketball",

};

NSLog (@ "%@", Dict4);

2. Find

Find object based on key

NSString *string1 = [Dict4 objectforkey:@ "name"];

NSLog (@ "%@", string1);

Subscript Method

NSLog (@ "%@", dict4[@ "name"]); // Two ways to do the same

3. get the length of the dictionary

NSLog (@ "%lu", [Dict4 Count]);

NSLog (@ "%lu", Dict4.count);

Nsmutabledictionary Variable Dictionary

The key in the dictionary is unique, and if a set method is used to add an element with the same name as a key in the dictionary , the value inside will be replaced, that is , if the dictionary does not have a key an element with the same name will be added;

1. Create an Object ( because it is a subclass of Nsdictionary, so there are nsdictionary methods,nsmutabledictionary have )

You can create an empty mutable dictionary

Nsmutabledictionary *mdict1 = [nsmutabledictionary dictionarywithcapacity:4];

of course, you can also create a dictionary based on existing dictionaries.

Nsmutabledictionary *mdict2 = [Nsmutabledictionary dictionarywithdictionary:dict4];

NSLog (@ "%@", mDict2);

2. Add, modify key-value pairs

[MDict1 addentriesfromdictionary:@{@ "height" : @ "203", @ "Weight" : @ "+"}] ;

NSLog (@ "%@", MDict1);

[MDict2 setobject:@ "203" Forkey:@ "height"];

NSLog (@ "%@", mDict2);

[MDict2 setValue:@ "America" Forkey:@ "Address"];

NSLog (@ "%@", mDict2);

/*

Setvalue:forkey: The key parameter type must be NSString * type, which is the method of NSObject object, which means that all OC Object has this method

Setobject:forkey: The key parameter type can be any type of object and is a unique method in the Nsmutabledictionary class

*/

3. Delete

Delete based on key

[MDict2 Removeobjectforkey:@ "name"];

Delete based on multiple keys

[MDict2 Removeobjectsforkeys:@[@ "hobby", @ "height"];

Delete all

[MDict2 removeallobjects];

NSLog (@ "%@", mDict2);

/**

* Nsset Immutable collection (elements cannot be duplicated, if there are multiple, only one is output, and is stored in an unordered order)

*/

Create a set object

Nsset *set1 = [Nsset setwithobjects:@ "Genie", @ "Weizhuang", @ "tianming", @ "Shaoyu", Nil];

NSLog (@ "%@", Set1);

arbitrarily remove an element ( not random )

NSString *str = [Set1 anyobject];

NSLog (@ "%@", str);

Remove all elements

Nsarray *sarray = [Set1 allobjects];

NSLog (@ "%@", Sarray);

gets the number of elements in the collection

NSLog (@ "%lu", Set1.count);

determines whether the object is in the collection

BOOL Ishasshaoyu = [Set1 containsobject:@ "Shaoyu"];

NSLog (@ "%d", Ishasshaoyu);

Nsmutableset Variable Set

Creating Objects

Nsmutableset *mset1 = [Nsmutableset setwithobjects:@ "Genie", @ "Weizhuang", @ "tianming", @ "Shaoyu", Nil];

NSLog (@ "%@", MSet1);

adding Objects

[MSet1 AddObject:@ "Gaoyue"];

NSLog (@ "%@", MSet1);

Delete Object

[MSet1 removeobject:@ "Shaoyu"];

NSLog (@ "%@", MSet1);

Simple operation of Nsdictionary and Nsset in OC