NSString *hanziText = @"我是中国人";  
if ([hanziText length]) {  
    NSMutableString *ms = [[NSMutableString alloc] initWithString:hanziText];  
    if (CFStringTransform((__bridge CFMutableStringRef)ms, 0, kCFStringTransformMandarinLatin, NO)) {  
        NSLog(@"pinyin: %@", ms);  
    }  
    if (CFStringTransform((__bridge CFMutableStringRef)ms, 0, kCFStringTransformStripDiacritics, NO)) {  
        NSLog(@"pinyin: %@", ms);  
    }  
}