float 类型的数据如何存进 NSArray NSMutableArray里面

//存入

 1       for (NSDictionary *dic in self.lrcList) {
 2 
 3         int i = 0;
 4 
 5         NSString *timeStr = [dic objectForKey:@"lrctime"];
 6 
 7         NSArray *array = [timeStr componentsSeparatedByString:@":"];//把时间转换成秒
 8 
 9         float currentTime = [array[0] floatValue] * 60 + [array[1] floatValue];
10 
11         NSNumber *number = [NSNumber numberWithFloat:currentTime];
12 
13         //[timearray addObject:number];
14 
15         timearray[i]=number;
16 
17         i++;
18 
19 }

//取出

1 [[timearray objectAtIndex:_numberOfLrc] floatValue]