将价钱（float）转换成带分隔符的价钱（字符串）

2988.32 --> 2,988.32

2988.00 --> 2,988

+ (NSString *)priceStrWithPrice:(float)price{    NSString *priceStr = [NSString stringWithFormat:@"%.2f", price];    NSString *intStr = [[priceStr componentsSeparatedByString:@"."] firstObject];    NSString *dotStr = [[priceStr componentsSeparatedByString:@"."] lastObject];        NSMutableArray *array = [NSMutableArray array];    while ([intStr length] > 3) {        NSString *right = [intStr substringFromIndex:[intStr length] - 3];        NSString *left= [intStr substringToIndex:[intStr length] - 3];        [array insertObject:right atIndex:0];        intStr = left;    }    [array insertObject:intStr atIndex:0];        NSString *result = [array componentsJoinedByString:@","];    if ([dotStr intValue] > 0) {        result = [NSString stringWithFormat:@"%@.%@", result, dotStr];    }    return result;}