Objective-c set object, objective-c set

Objective-c set object, objective-c set

A collection (NSSet) is a combination of Single-value objects. operations on a set object include: search, add, and delete members in the Set (the function of a variable set), and compare the two sets, calculates the intersection and union of two sets.

Next let's take a look at the (NSSet) method:

　　

 

 

1) Build a set

　　

1 // three methods for building a set 2 3 # import <Foundation/Foundation. h> 4 5 int main (int argc, const char * argv []) {6 @ autoreleasepool {7 NSSet * set1 = [NSSet setWithObjects: @ "zhangsan ", @ "lisi", @ "wangwu", nil]; 8 for (NSString * temp1 in set1) {9 NSLog (@ "temp1 = % @", temp1 ); 10} 11 12 NSArray * array = @ [@ "aa", @ "bb", @ "cc"]; 13 NSSet * set2 = [NSSet setWithArray: array]; 14 for (NSString * temp2 in set2) 15 NSLog (@ "temp2 = % @", temp2); 16 17 NSSet * set3 = [[NSSet alloc] initWithObjects: @ "aa", @ "bb" @ "cc", nil]; 18 for (NSString * temp3 in set3) 19 NSLog (@ "temp3 =%@", temp3 ); 20} 21}

2) traversal of a set

　　

 1 #import <Foundation/Foundation.h> 2  3 @interface NSString (print) 4  5 - (void)print; 6 - (void)show:(NSString *)str; 7  8 @end 9 10 @implementation NSString (print)11 12 - (void)print{13     NSLog(@"%@",self);14 }15 - (void)show:(NSString *)str{16     NSLog(@"%@ : %@",str,self);17 }18 19 @end20 int main(int argc , const char *argv[]){21     @autoreleasepool {22         NSSet *set = [NSSet setWithObjects:@"zhangsan",@"lisi",@"wangwu",nil];23         for(NSString *temp in set)24             NSLog(@"temp = %@",temp);25         26         NSLog(@"--------------------------");27         [set enumerateObjectsUsingBlock:^(id obj, BOOL *stop) {28             NSLog(@"obj = %@",obj);29         }];30         31         NSLog(@"---------------------------");32         [set makeObjectsPerformSelector:@selector(print)];33         34         NSLog(@"----------------------------");35         [set makeObjectsPerformSelector:@selector(show:) withObject:@"this is "];36         37         NSLog(@"-----------------------------");38         NSEnumerator *emr = [set objectEnumerator];39         NSString *temp = nil;40         while(temp = [emr nextObject])41             NSLog(@"temp = %@",temp);42     }43     return 0;44 }

 

3) Comparison of Sets

　　

 1 #import <Foundation/Foundation.h> 2  3 int main(int argc , const char *argv[]){ 4     @autoreleasepool { 5         NSSet *set = [NSSet setWithObjects:@"zhangsan",@"lisi",@"wangwu",nil]; 6         for(NSString *temp in set) 7             NSLog(@"temp = %@",temp); 8          9         BOOL ishas = [set containsObject:@"lisi"];10         if(ishas)11             NSLog(@"has lisi");12         else13             NSLog(@"no lisi");14         15         NSString *str = [set member:@"aaaa"];16         NSLog(@"str = %@",str);17         18         NSSet *set2 = [set setByAddingObject:@"xiaoliu"];19         NSLog(@"set2 = %@",set2);20         21         NSSet *set3 = [set setByAddingObjectsFromArray:@[@"aa",@"bb",@"cc"]];22         NSLog(@"set3 = %@",set3);23         24         NSSet *set4 = [NSSet setWithObjects:@"zhangsan",@"lisi",nil];25         BOOL issub = [set4 isSubsetOfSet:set];26         if(issub)27             NSLog(@"set4 is set sub class");28         else29             NSLog(@"set4 no set sub class");30         31         BOOL isinterset = [set intersectsSet:set4];32         if(isinterset)33             NSLog(@"set and set4 has intersect");34         else35             NSLog(@"set and set4 no intersect");36         37         BOOL isequal = [set isEqualToSet:set2];38         if(isequal)39             NSLog(@"set = set2");40         else41             NSLog(@"set != set2");42         43     }44     return 0;45 }

 

 

4) variable set (NSMutable)

　　

 

 

The following example shows how to use a variable set:

　　

 1 #import <Foundation/Foundation.h> 2  3 @interface NSString (print) 4 -(void)print; 5 -(void)show:(NSString *)str; 6 @end 7  8 @implementation NSString(print) 9 -(void)print{10     NSLog(@"%@",self);11 }12 -(void)show:(NSString *)str{13     NSLog(@"%@ : %@",str,self);14 }15 @end16 17 int main(int argc,char **argv){18     @autoreleasepool {19         NSMutableSet *mset = [NSMutableSet setWithObjects:@"zhangsan",@"lisi",@"wangwu", nil];20         21         [mset addObject:@"zhaoliu"];22         NSLog(@"mset = %@",mset);23         24         [mset addObjectsFromArray:@[@"111",@"222",@"333"]];25         NSLog(@"mset = %@",mset);26         27         [mset removeObject:@"111"];28         NSLog(@"mset = %@",mset);29         30         NSSortDescriptor *sortdesr = [[NSSortDescriptor alloc] initWithKey:nil ascending:YES];31         NSArray *sortset = [mset sortedArrayUsingDescriptors:@[sortdesr]];32         NSLog(@"mset sort = %@",sortset);33         34         NSArray *array = [mset allObjects];35         NSLog(@"array = %@",array);36         NSSet *set2 = [NSSet setWithArray:array];37         NSLog(@"set2 = %@",set2);38         39         NSString *str = [mset anyObject];40         NSLog(@"str = %@",str);41         42         [mset setSet:set2];43         NSLog(@"mset = %@",mset);44         45         [mset removeAllObjects];46         NSLog(@"mset = %@",mset);47     }48 }