Objective-C Syntax: What about a set object (9)

Objective-C Syntax: What about a set object?

If the original Yusong Momo article is reprinted, please note: It is reprinted to my independent domain name blogYusong Momo program Research Institute, Original address: http://www.xuanyusong.com/archives/425


The key words of the Set object are nsset and nsmutableset. The former is an immutable set, and the latter is a mutable set. In objective-C, most data structures have two types of data: variable and immutable. The set here is similar to the set in Java and C. The usage is basically the same. However, in objective-C, the same set can store data of different objects. The following is a clear example.



1. Create an unchangeable set object

[Nsnumber numberwithinteger: 9527]; because the collection can only store objects, if you want to save a number, you must convert the number into an object before saving it. [Nsset setwithobjects:...]: Creates a set object and initializes a value in the set. The NIL flag must be used at the end. [Set count]; get the length of the combined object. [Set containsobject:...]: determines whether an input object exists in this set and returns the bool value. [Set objectenumerator]: puts the set into the iterator. [Enumerator nextobject]: to obtain the data of the next node in the iterator, use the while traversal tool to traverse the objects in the Set object. [Set isequaltoset: objset]: determines whether the two sets are completely equal. , Returns the bool value.
[ Set issubsetofset: objset ]: Determines whether all data in the set is equal to that in the objeset set, Returns the bool value. [Set istersectset: Objset ]: Determine that at least one data in the set is equal to that in the objeset set, Returns the bool value.

# Import <uikit/uikit. h> # import "myclass. H "int main (INT argc, char * argv []) {ngutoreleasepool * Pool = [[ngutoreleasepool alloc] init]; // Add our test code // create a collection nsset * Set = [nsset setwithobjects: @ "Yu Song Momo", @ "15810463139", [nsnumber numberwithinteger: 9527], nil]; // number of sets int COUNT = [set count]; nslog (@ "number in the Set: % d", count ); // check whether the collection contains nsstring * STR = @ "Yu Song Momo"; if ([set containsobject: Str]) {nslog (@ "contains % @ This object ", STR);} // iterator traverses nsenumerator * enumerator = [set objectenumerator]; nsobject * object = [enumerator nextobject]; while (object! = Nil) {nslog (@ "iterator traversing data in the Set: % @", object); object = [enumerator nextobject];} // quick enumeration traversal for (nsobject * object in set) {nslog (@ "quick enumeration traversal of data in the Set: % @", object);} int retval = uiapplicationmain (argc, argv, nil, nil); [pool release]; return retval ;}

2. Create a variable set object

Nsmutableset inherits nsset, so you can use the parent class method.

[Nsmutableset setwithcapacity: 10]: Creates a variable set object and the initialization length is 10. [Set addobject: OBJ]: dynamically add objects to a set. [Set removeobject: OBJ]: deletes an object in the set. [Set removeallobjects]: deletes all objects in the set. [Set unionset: OBJ]: Adds all data of an OBJ set to the set. [Set minusset: OBJ]: deletes all data of an OBJ set from the set. [Set intersectset]: deletes all data that does not contain the OBJ set from the collection.

# Import <uikit/uikit. h> # import "myclass. H "int main (INT argc, char * argv []) {ngutoreleasepool * Pool = [[ngutoreleasepool alloc] init]; // Add our test code // create a set nsmutableset * Set = [nsmutableset setwithcapacity: 10]; // Add data [set addobject: @ "Yu Song Momo"]; [set addobject: [nsnumber numberwithint: 9527]; // Add data to delete nsstring * STR = @ "delete me"; [set addobject: Str]; // delete it [set removeobject: Str]; // fast enumeration traversal for (nsobject * object in set) {nslog (@ "quick enumeration traversing data in the Set: % @", object);} int retval = uiapplicationmain (argc, argv, nil, nil); [pool release]; return retval ;}

The beauty of the set, not an explanation! Wow ~ Good night !!!