- (NSString *)transform:(NSString *)chinese {

    // 将NSString转化为NSMutableString,如:苹果

    NSMutableString *pinyin = [chinese mutableCopy];

    // 将汉字转化为拼音,带音调,如:píng guǒ

    CFStringTransform((__bridge CFMutableStringRef)pinyin, NULL, kCFStringTransformMandarinLatin, NO);

    NSLog(@"带音调的拼音:%@", pinyin);

    // 将汉字转化为拼音,不带音调,如:ping guo

    CFStringTransform((__bridge CFMutableStringRef)pinyin, NULL, kCFStringTransformStripCombiningMarks, NO);

    NSLog(@"不带音调的拼音:%@", pinyin);

    // 返回结果

    return pinyin;

}