根据类型限制UIDatePicker控制，例如(成人、儿童、婴儿)目标C

// 设置日期选择器的类型
UIDatePicker *datePicker = [[UIDatePicker alloc] init];
datePicker.datePickerMode = UIDatePickerModeDate;

// 设置类型
NSString *type = @"成人";
NSDate *currentDate = [NSDate date];
NSDate *minDate;
NSDate *maxDate;

if ([type isEqualToString:@"成人"]) {
    // 成人类型的最小日期为18年前的当前日期
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
    dateComponents.year = -18;
    minDate = [calendar dateByAddingComponents:dateComponents toDate:currentDate options:0];
    
    // 最大日期为当前日期
    maxDate = currentDate;
} else if ([type isEqualToString:@"儿童"]) {
    // 儿童类型的最小日期为3岁前的当前日期
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
    dateComponents.year = -3;
    minDate = [calendar dateByAddingComponents:dateComponents toDate:currentDate options:0];
    
    // 最大日期为10岁前的当前日期
    NSDateComponents *maxDateComponents = [[NSDateComponents alloc] init];
    maxDateComponents.year = -10;
    maxDate = [calendar dateByAddingComponents:maxDateComponents toDate:currentDate options:0];
} else if ([type isEqualToString:@"婴儿"]) {
    // 婴儿类型的最大日期为1岁前的当前日期
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *dateComponents = [[NSDateComponents alloc] init];
    dateComponents.year = -1;
    maxDate = [calendar dateByAddingComponents:dateComponents toDate:currentDate options:0];
    
    // 最小日期为100年前的当前日期
    NSDateComponents *minDateComponents = [[NSDateComponents alloc] init];
    minDateComponents.year = -100;
    minDate = [calendar dateByAddingComponents:minDateComponents toDate:currentDate options:0];
}

// 设置日期选择器的最大和最小日期
[datePicker setMinimumDate:minDate];
[datePicker setMaximumDate:maxDate];

// 添加值变化事件监听
[datePicker addTarget:self action:@selector(datePickerValueChanged:) forControlEvents:UIControlEventValueChanged];