- (NSString *)firstCharactor:(NSString *)aString

{

//转成了可变字符串

NSMutableString *str = [NSMutableString stringWithString:aString];

//先转换为带声调的拼音

CFStringTransform((CFMutableStringRef)str,NULL, kCFStringTransformMandarinLatin,NO);

//再转换为不带声调的拼音

CFStringTransform((CFMutableStringRef)str,NULL, kCFStringTransformStripDiacritics,NO);

//转化为大写拼音

NSString *pinYin = [str capitalizedString];

//获取并返回首字母

return [pinYin substringToIndex:1];

}