NSArray NSDictionary一些用法

     //从字符串分割到数组－ componentsSeparatedByString:
     NSString *str = ［NSString alloc] initWithString:@"a,b,c,d"];
     NSLog(@"str:%@",str);
     NSArray *array = [str componentsSeparatedByString:@","];
     NSLog(@"array:%@",array);
     [str release]; 

     //从数组合并元素到字符串- componentsJoinedByString:
     NSArray *array = ［NSArray alloc] initWithObjects:@"One",@"a",@"b",@"c",nil];
     NSString *string = [array componentsJoinedByString:@","];
     NSLog(@"string:%@",string);

    //给数组分配容量
    NSArray *array = [NSMutableArray arrayWithCapacity:];

    //在数组末尾添加对象

    NSMutableArray *array = [NSMutableArray arrayWithObjects:@"a",@"b",@"c",nil];
    [array addObject:@"d"];
    NSLog(@"array:%@",array);

    //删除数组中指定索引处对象
    NSMutableArray *array = [NSMutableArray arrayWithObjects:@"a",@"b",@"c",nil];
    [array removeObjectAtIndex:];
    NSLog(@"array:%@",array);

     //数组枚举
     NSMutableArray *array = [NSMutableArray arrayWithObjects: @"a",@"b",@"c",nil];
     NSEnumerator *enumerator;
     enumerator = [array objectEnumerator];
     id enum;
     while (enum = [enumerator nextObject]) {
         NSLog(@"enum:%@",enum);
 8      }

     //reverseObjectEnumerator;从后向前
     NSMutableArray *array = [NSMutableArray arrayWithObjects:@"a",@"b",@"c",nil];
     NSEnumerator *enumerator;
     enumerator = [array reverseObjectEnumerator];
     id object;
     while (object = [enumerator nextObject]) {
 7         NSLog(@"object:%@",object);
 8     }

     //快速枚举
     NSMutableArray *array = [NSMutableArray arrayWithObjects:
     @"a",@"b",@"c",nil];
     for(NSString *string in array)
     {
         NSLog(@"string:%@",string);
     }

1    //创建字典
2    NSDictionary *dictionary = ［NSDictionary alloc] initWithObjectsAndKeys:@"a",@"b",@"c",nil];
3    NSString *string = [dictionary objectForKey:@"One"];
4    NSLog(@"string:%@",string);
5    NSLog(@"dictionary:%@",dictionary);
6    [dictionary release];

     //创建可变字典
     NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];
     //添加字典
     [dictionary setObject:@"One" forKey:@""];
     [dictionary setObject:@"Two" forKey:@""];
     [dictionary setObject:@"Three" forKey:@""];
     [dictionary setObject:@"Four" forKey:@""];
     NSLog(@"dictionary:%@",dictionary);

     //删除指定的字典
     [dictionary removeObjectForKey:@""];
     NSLog(@"dictionary:%@",dictionary);

     //NSDictionary 初始化
     NSDictionary *dictionary = [NSDictionary dictionaryWithObjectsAndKeys:@"a", @"b", @"c", nil];
     //NSDictionary 个数
     NSLog(@"dictionary count: %ld", [dictionary count]);

     //NSDictionary 枚举keys/values
     NSEnumerator *enum = [dictionary objectEnumerator];
     for (NSObject *enum in enum) {
         NSLog(@"enum: %@", enum);
      }

     NSDictionary *dictionary = [NSDictionary dictionaryWithObjectsAndKeys:@"a",@"b",@"c", nil];

     //得到词典的数量
     int count = [dictionary count];
     NSLog(@"词典的数量为： %d",count);

     //得到词典中所有KEY值
     NSEnumerator * enumeratorKey = [dictionary keyEnumerator];

     //快速枚举遍历所有KEY的值
     for (NSObject *object in enumeratorKey) {
         NSLog(@"遍历KEY的值: %@",object);
     }

     //得到词典中所有Value值
      NSEnumerator * enumeratorValue = [dictionary objectEnumerator];

     //快速枚举遍历所有Value的值
     for (NSObject *object in enumeratorValue) {
         NSLog(@"遍历Value的值: %@",object);
     }

     //通过KEY找到value
     NSObject *object = [dictionary objectForKey:@"a"];

     if (object != nil) {
         NSLog(@"通过KEY找到的value是: %@",object);
     }