NSSet -- 集合&&NSMutableSet -- 可变集合

//
//  main.m
//  OC05-task-03
//
//  Created by Xin the Great on 15-1-25.
//  Copyright (c) 2015年 Xin the Great. All rights reserved.
//

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        // insert code here...
        ///////////////NSSet -- 集合////////////////
        
        //不可变
        
        //集合没有重复的元素,而且无序
        NSSet *set = [[NSSet alloc] initWithObjects:@"a",@"b",@"a", nil];
        NSLog(@"set is %@",set);
        
        //类方法初始化
        NSSet *set1 = [NSSet setWithObjects:@"1",@"2",@"x",@"y", nil];
        NSLog(@"set1 is %@",set1);

        
        //获取集合元素的个数
        NSUInteger count = [set1 count];
        NSLog(@"count is %ld", count);
        
        //获取所有的集合元素
        NSArray *list = [set1 allObjects];
        NSLog(@"list is %@", list);
        
        //获得任意一个元素
        id value = [set1 anyObject];
        NSLog(@"value is %@", value);
        
        //判断集合中是否包含某一个元素
        BOOL isTure = [set1 containsObject:@"u"];
        NSLog(@"isTure is %d", isTure);
        
        
        ////////////////NSMutableSet -- 可变集合////////////
        NSMutableSet *mutableSet = [NSMutableSet set];
        //添加元素
        [mutableSet addObject:@"x"];
        NSLog(@"mutableSet is %@", mutableSet);
        
        //批量添加
        NSArray *values = @[@"1", @"2", @"3", @"3", @"3"];
        [mutableSet addObjectsFromArray:values];
        NSLog(@"mutableSet is %@", mutableSet);
        
        //删除元素
        [mutableSet removeObject:@"x"];
        NSLog(@"mutableSet is %@", mutableSet);
        
        //删除所有
        [mutableSet removeAllObjects];
        NSLog(@"mutableSet is %@", mutableSet);
        
        
        //集合的遍历
        NSSet *set3 = [NSSet setWithObjects:@"1",@"2",@"3",@"4",@"5",@"6", nil];
        
        //传统遍历，对集合来说必须要转化为数组
        NSArray *arr3 = [set3 allObjects];
        for (int i = 0; i < set3.count; i++) {
            //不可以通过下标取元素
//            NSString *str = set3[i];
            NSString *str = arr3[i];
            NSLog(@"str is %@", str);
        }
        
        NSLog(@"------------------------------------------");
        //快速遍历
        for (NSString *str in set3) {
            NSLog(@"str is %@", str);
        }



        
    }
    return 0;
}

NSSet -- 集合&&NSMutableSet -- 可变集合

原文：http://blog.csdn.net/zuojx1013/article/details/43202391