NSArray,NSSet,NSDictionary的遍历,基本使用集锦

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NSArray *array = [NSArray arrayWithObjects:@"zhangsan",@"lisi",@"wangwu",@"zhaoda", nil];
        //如何把  数组元素 一一取出？
        //方法一：for循环
        for (int i = 0; i < [array count]; i++) {
            NSString *obj = [array objectAtIndex:i];
            NSLog(@"%@",obj);
        }
        NSLog(@"----------");
        //方法二：使用枚举器NSEnumerator
        NSEnumerator *enumerator = [array reverseObjectEnumerator];
        NSString *obj = nil;
        while (obj = [enumerator nextObject]) {
            NSLog(@"obj = %@",obj);
        }
        NSLog(@"----------");

        //方法三：快速枚举 forin
        for (NSString *obj in array) {
            NSLog(@"%@",obj);
        }
        NSLog(@"----------");
        //方法四：使用专业的枚举方式（blocks等）
        [array enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
            NSLog(@"!!!%@ %lu",obj,idx);
            if(idx == 1)
            {
                *stop = YES;
            }
        }];
        
        NSLog(@"#########");
        
        //字典四种方法同上！
        NSDictionary *dic = [NSDictionary dictionaryWithObjectsAndKeys:@"cui",@"name",@"18",@"age",@"nan",@"gender", nil];
        //如何把  字典元素  一一取出？//字典没有下标概念  只能靠key区分对象
        NSArray *allKeys = [dic allKeys];
        NSArray *allValue = [dic allValues];
        for(int i = 0;i < [dic count];i++){
            NSString *key = [allKeys objectAtIndex:i];
            //NSString *obj =[allValue objectAtIndex:i];
            NSString *obj = [dic objectForKey:key];
            NSLog(@"key = %@ obj = %@",key,obj);
        }
        
        
        NSEnumerator *en = [dic keyEnumerator];
        NSString *key = nil;
        while (key = [en nextObject]) {
            NSLog(@"%@ = %@",key,[dic objectForKey:key]);
        }
        for (NSString *key in dic) {
            NSLog(@"-%@--%@",key,[dic objectForKey:key]);
        }

        
        
        NSLog(@"++++++++++++");
        NSSet *set = [NSSet setWithObjects:@"guangmu",@"duowen",@"zengchang",@"chiguo", nil];
        //如何把  集合元素 一一取出？
        NSArray *objects = [set allObjects];
        for (int i = 0; i < [objects count]; i++) {
            NSLog(@"%@",[objects objectAtIndex:i]);
        }
        
        NSEnumerator *e = [set objectEnumerator];
        NSString *o = nil;
        while (o = [e nextObject]) {
            NSLog(@"%@",o);
        }
        for (NSString *obj in set) {
            NSLog(@"=%@",obj);
        }
        
    }