我正在使用ABAddressBookRegisterExternalChangeCallback来获取用户的AddressbookBook中的外部更改。我使用以下代码注册回调：
ABAddressBookRef ntificationaddressbook = ABAddressBookCreate();
ABAddressBookRegisterExternalChangeCallback(ntificationaddressbook, MyAddressBookExternalChangeCallback, self);
当调用此回调时，将成功调用MyAddressBookExternalChangeCallback
void MyAddressBookExternalChangeCallback (ABAddressBookRef ntificationaddressbook,CFDictionaryRef info,void *context)
{
NSLog(@"Changed Detected......");
}
我有以下问题：
不幸的是，如果那不可能，那么像viber，tango，watsapp这样的应用程序如何获取更改信息？
请帮忙。提前谢谢。
答案 0 :(得分：9)
我找到了解决方案来查找地址簿中的更改内容。我不确定它是否是一个精确的，但有些是如何工作的。
为地址簿创建回调通知： -
ABAddressBookRef ntificationaddressbook = ABAddressBookCreate();
ABAddressBookRegisterExternalChangeCallback(ntificationaddressbook, MyAddressBookExternalChangeCallback, self);
比发生通知时添加以下代码： -
void MyAddressBookExternalChangeCallback (ABAddressBookRef ntificationaddressbook,CFDictionaryRef info,void *context)
{
NSTimeInterval timeStampone = [[NSDate date] timeIntervalSince1970];
NSNumber *timeStamponeobj= [NSNumber numberWithDouble: timeStampone];
NSLog(@"Start Process");
NSUserDefaults *userdefs = [[NSUserDefaults alloc]init];
NSMutableArray *arraytemp = [[NSMutableArray alloc]init];
CFArrayRef peopleRefs = ABAddressBookCopyArrayOfAllPeopleInSource(ntificationaddressbook, kABSourceTypeLocal);
NSMutableArray *changedrecords = [[NSMutableArray alloc]init];
ABAddressBookRevert(ntificationaddressbook);
CFIndex count = CFArrayGetCount(peopleRefs);
for (CFIndex i=0; i < count; i++) {
ABRecordRef ref = CFArrayGetValueAtIndex(peopleRefs, i);
NSDate* datemod = ( NSDate *)(ABRecordCopyValue(ref, kABPersonModificationDateProperty));
NSDate *lastopened = [userdefs valueForKey:@"LastOpenedDate"];
NSTimeInterval datemodifiedtime =[datemod timeIntervalSince1970];
NSNumber *modifieddatenumber= [NSNumber numberWithDouble: datemodifiedtime];
NSTimeInterval lastopeddate = [lastopened timeIntervalSince1970];
NSNumber *lastopenednumber= [NSNumber numberWithDouble: lastopeddate];
if ([modifieddatenumber intValue]>[lastopenednumber intValue]) {
ABRecordRef aSource = CFArrayGetValueAtIndex(peopleRefs,i);
int recordid = ABRecordGetRecordID(aSource);
[changedrecords addObject:[NSString stringWithFormat:@"%d",recordid]];
}
}
NSString *arraystring= [changedrecords componentsJoinedByString:@","];
[userdefs setValue:arraystring forKey:@"ArrayOfChangedPeopleString"];
[userdefs setValue:changedrecords forKey:@"ArrayOfChangedPeople"];
//-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
if ([arraystring isEqualToString:@"(null)"]) {
arraystring = [arraystring stringByReplacingOccurrencesOfString:@"(null)" withString:@""];
}
NSLog(@"arraychangedstring= %@ and length = %d",arraystring,arraystring.length);
NSLog(@"Must send data to the server here for this changed people array= %@",changedrecords);
if (arraystring.length>2) {
NSLog(@"inside if");
ABAddressBookRef addressBook = ABAddressBookCreate();
CFArrayRef allSources = ABAddressBookCopyArrayOfAllPeople( addressBook );
[userdefs setValue:@"" forKey:@"ArrayOfChangedPeopleString"];
[userdefs setValue:@"" forKey:@"ArrayOfChangedPeople"];
for (int i = 0; i<[changedrecords count]; i++) {
NSString *recordid= [changedrecords objectAtIndex:i];
int nPeople = [recordid intValue];
[IntoochUtil current_function_name:@"Inside getcontactdetails - Start"];
if(nPeople != 0){
// for (CFIndex i = nPeople_start; i < (nPeople_end); i++)
// {
// NSString *reocrdid = [NSString stringWithFormat: @"Record %ld",i];
// NSLog(@"Recordid= %@",reocrdid);
NSMutableDictionary *dict = [[NSMutableDictionary alloc]init];
//common field
NSString *first_name =nil;
NSString *mid_name = nil ;
NSString *last_name =nil ;
NSString *basic_email =nil ;
NSString *basic_mobile =nil ;
NSString *other_phone=nil;
NSString *pager_phone= nil;
//personal filed
NSString *Home_email =nil ;
NSString*home_mobile =nil ;
NSString*home_address =nil;
//business filed
NSString *work_email =nil ;
NSString *company_name =nil ;
NSString *job_title =nil ;
NSString*work_mobile =nil ;
NSString *iphone = nil;
NSString *main = nil;
NSString *work_address =nil ;
NSString *home_fax, *work_fax, *other_fax =nil;
NSString *birthday = nil;
// NSString *blogs = nil;
NSString *record_id;
ABRecordRef aSource = ABAddressBookGetPersonWithRecordID(addressBook, nPeople);
// Fetch all groups included in the current source
// Getting Record id from address book
int recordid = ABRecordGetRecordID(aSource);
record_id = [NSString stringWithFormat:@"%d",recordid];
// Getting Names from address book
// CFStringRef firstName = ABRecordCopyValue(aSource, kABPersonFirstNameProperty);
first_name= ABRecordCopyValue(aSource, kABPersonFirstNameProperty);
// first_name=[NSString stringWithFormat:@"%@",firstName];
// CFRelease(firstName);
// NSLog(@"First name= %@",first_name);
NSMutableDictionary *dict_name = [[NSMutableDictionary alloc]init];
if (!([first_name isEqualToString:@"(null)"]|| first_name == nil || first_name.length ==0))
{
[dict_name setValue:first_name forKey:@"FirstName"];
}
[first_name release];
mid_name= ABRecordCopyValue(aSource, kABPersonMiddleNameProperty);
// NSLog(@"mid name = %@",mid_name);
// CFRelease(midname);
if (!([mid_name isEqualToString:@"(null)"]|| mid_name == nil || mid_name.length ==0))
{
[dict_name setValue:mid_name forKey:@"MiddleName"];
}
[mid_name release];
last_name = ABRecordCopyValue(aSource, kABPersonLastNameProperty);
// NSLog(@"Last Name= %@",last_name);
// CFRelease(lastName);
if (!([last_name isEqualToString:@"(null)"]|| last_name == nil || last_name.length ==0))
{
[dict_name setValue:last_name forKey:@"LastName"];
}
[last_name release];
NSString *dictNamestring = [NSString stringWithFormat:@"%@",dict_name];
if (!([dictNamestring isEqualToString:@"(null)"]|| dictNamestring == nil || dictNamestring.length <4))
{
[dict setValue:dict_name forKey:@"Names"];
}
// [dict_name release];
// Getting Phone numbers from address book
NSMutableDictionary *dict_phone = [[NSMutableDictionary alloc]init];
ABMultiValueRef phones =(NSString*)ABRecordCopyValue(aSource, kABPersonPhoneProperty);
NSString* mobileLabel;
for(CFIndex i = 0; i < ABMultiValueGetCount(phones); i++) {
mobileLabel = (NSString*)ABMultiValueCopyLabelAtIndex(phones, i);
if([mobileLabel isEqualToString:(NSString *)kABPersonPhoneMobileLabel])
{
home_mobile = (NSString*)ABMultiValueCopyValueAtIndex(phones, i) ;
[dict_phone setValue:home_mobile forKey:@"Mobile"];
}
else if ([mobileLabel isEqualToString:(NSString*)kABHomeLabel])
{
basic_mobile = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:basic_mobile forKey:@"Home"];
}
else if([mobileLabel isEqualToString:(NSString *)kABWorkLabel])
{
work_mobile = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:work_mobile forKey:@"Work"];
}
else if([mobileLabel isEqualToString:(NSString *)kABPersonPhoneIPhoneLabel])
{
iphone = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:iphone forKey:@"iPhone"];
}
else if([mobileLabel isEqualToString:(NSString *)kABPersonPhoneMainLabel])
{
main = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:main forKey:@"Main"];
}
else if ([mobileLabel isEqualToString:(NSString*)kABOtherLabel])
{
other_phone = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:other_phone forKey:@"OtherPhone"];
}
else if ([mobileLabel isEqualToString:(NSString*)kABPersonPhonePagerLabel])
{
pager_phone = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:pager_phone forKey:@"Pager"];
}
else
{
NSLog(@"%@ label is not processed",mobileLabel);
}
}
CFRelease(phones);
NSString *dictphonestring = [NSString stringWithFormat:@"%@",dict_phone];
if (!([dictphonestring isEqualToString:@"(null)"]|| dictphonestring == nil || dictphonestring.length <4))
{
[dict setValue:dict_phone forKey:@"PhoneNos"];
}
// [dict_phone release];
// Getting Fax numbers from address book
NSMutableDictionary *dict_fax = [[NSMutableDictionary alloc]init];
ABMultiValueRef faxes =(NSString*)ABRecordCopyValue(aSource, kABPersonPhoneProperty);
NSString* FaxLabel;
for(CFIndex i = 0; i < ABMultiValueGetCount(faxes); i++) {
FaxLabel = (NSString*)ABMultiValueCopyLabelAtIndex(faxes, i);
if([FaxLabel isEqualToString:(NSString *)kABPersonPhoneHomeFAXLabel])
{
home_fax = (NSString*)ABMultiValueCopyValueAtIndex(faxes, i) ;
[dict_fax setValue:home_fax forKey:@"Home"];
}
if ([FaxLabel isEqualToString:(NSString*)kABPersonPhoneWorkFAXLabel])
{
work_fax = (NSString*)ABMultiValueCopyValueAtIndex(faxes, i);
[dict_fax setValue:work_fax forKey:@"Work"];
}
if([FaxLabel isEqualToString:(NSString *)kABPersonPhoneOtherFAXLabel])
{
other_fax = (NSString*)ABMultiValueCopyValueAtIndex(faxes, i);
[dict_fax setValue:other_fax forKey:@"Other"];
}
}
CFRelease(faxes);
NSString *dictfaxstring = [NSString stringWithFormat:@"%@",dict_fax];
if (!([dictfaxstring isEqualToString:@"(null)"]|| dictfaxstring == nil || dictfaxstring.length <4))
{
[dict setValue:dict_fax forKey:@"FaxNos"];
}
[dict_fax release];
// Getting emails from address book
ABMultiValueRef email = ABRecordCopyValue(aSource, kABPersonEmailProperty);
NSMutableDictionary *dict_email = [[NSMutableDictionary alloc]init];
NSString* email_lbl;
for(CFIndex i = 0; i < ABMultiValueGetCount(email); i++) {
email_lbl = (NSString*)ABMultiValueCopyLabelAtIndex(email, i);
if([email_lbl isEqualToString:(NSString *)kABHomeLabel])
{
Home_email = [(NSString*)ABMultiValueCopyValueAtIndex(email, i)retain];
[dict_email setValue:Home_email forKey:@"Home"];
}
else if([email_lbl isEqualToString:(NSString *)kABWorkLabel])
{
work_email = [(NSString*)ABMultiValueCopyValueAtIndex(email, i)retain];
[dict_email setValue:work_email forKey:@"Work"];
}
else if([email_lbl isEqualToString:(NSString *)kABOtherLabel])
{
basic_email = [(NSString*)ABMultiValueCopyValueAtIndex(email, i)retain];
[dict_email setValue:basic_email forKey:@"Other"];
}
else
{
NSLog(@"%@ label is processed as other",email_lbl);
basic_email = [(NSString*)ABMultiValueCopyValueAtIndex(email, i)retain];
[dict_email setValue:basic_email forKey:@"Other"];
}
}
CFRelease(email);
NSString *dictemailstring = [NSString stringWithFormat:@"%@",dict_email];
if (!([dictemailstring isEqualToString:@"(null)"]|| dictemailstring == nil || dictemailstring.length <4))
{
[dict setValue:dict_email forKey:@"Emails"];
}
// [dict_email release];
company_name = ABRecordCopyValue(aSource, kABPersonOrganizationProperty);
// NSLog(@"Company name= %@",company_name);
job_title = ABRecordCopyValue(aSource, kABPersonJobTitleProperty);
// NSLog(@"Job title= %@",job_title);
NSDate *birthdate = ABRecordCopyValue(aSource, kABPersonBirthdayProperty);
NSString *birthdate_string = [NSString stringWithFormat:@"%@",birthdate];
if (!([birthdate_string isEqualToString:@"(null)"]|| birthdate_string == nil || birthdate_string.length ==0)) {
NSDateComponents *components = [[NSCalendar currentCalendar] components:NSDayCalendarUnit | NSMonthCalendarUnit | NSYearCalendarUnit fromDate:birthdate];
NSInteger day = [components day];
NSInteger month = [components month];
NSInteger year = [components year];
birthday = [NSString stringWithFormat:@"%d-%d-%d",day,month,year];
NSLog(@"birthday= %@",birthday);
}
[birthdate release];
// Getting addressess from address book
ABMultiValueRef address =(NSString*)ABRecordCopyValue(aSource, kABPersonAddressProperty);
NSDictionary *dict_address = [[NSMutableDictionary alloc]init];
NSString* addLabel;
for(CFIndex i = 0; i < ABMultiValueGetCount(address); i++) {
addLabel=(NSString*)ABMultiValueCopyLabelAtIndex(address, i);
if ([addLabel isEqualToString:(NSString*)kABWorkLabel]) {
NSMutableDictionary *dict_work_add = [(NSMutableDictionary *)ABMultiValueCopyValueAtIndex(address, i)retain];
work_address=[NSString stringWithFormat:@"%@ %@ %@ %@ %@",[dict_work_add objectForKey:@"Street"],[dict_work_add objectForKey:@"City"],[dict_work_add objectForKey:@"State"],[dict_work_add objectForKey:@"Country"],[dict_work_add objectForKey:@"ZIP"]] ;
work_address = [work_address stringByReplacingOccurrencesOfString:@"(null)" withString:@""];
work_address = [work_address stringByReplacingOccurrencesOfString:@"\n" withString:@""];
// NSLog(@"work address = [%@] and length= %d",work_address,work_address.length);
if (!([work_address isEqualToString:@"(null)"]|| work_address == nil || work_address.length ==0))
{
[dict_address setValue:work_address forKey:@"Work"];
}
}
if ([addLabel isEqualToString:(NSString*)kABHomeLabel])
{
NSMutableDictionary *dict_home_add = [(NSMutableDictionary *)ABMultiValueCopyValueAtIndex(address, i)retain];
home_address = [NSString stringWithFormat:@"%@ %@ %@ %@ %@",[dict_home_add objectForKey:@"Street"],[dict_home_add objectForKey:@"City"],[dict_home_add objectForKey:@"State"],[dict_home_add objectForKey:@"Country"],[dict_home_add objectForKey:@"ZIP"]];
home_address = [home_address stringByReplacingOccurrencesOfString:@"(null)" withString:@""];
home_address = [home_address stringByReplacingOccurrencesOfString:@"\n" withString:@""];
// NSLog(@"home address = [%@] and length= %d",home_address,home_address.length);
if (!([home_address isEqualToString:@"(null)"]|| home_address == nil || home_address.length ==0))
{
[dict_address setValue:home_address forKey:@"Home"];
}
}
}
CFRelease(address);
NSString *dictaddrssstring = [NSString stringWithFormat:@"%@",dict_address];
if (!([dictaddrssstring isEqualToString:@"(null)"]|| dictaddrssstring == nil || dictaddrssstring.length <4))
{
[dict setValue:dict_address forKey:@"Addresses"];
}
[dict_address release];
// Getting Social Networks from address book
ABMultiValueRef social =(NSString*)ABRecordCopyValue(aSource, kABPersonSocialProfileProperty);
NSMutableDictionary *dict_social = [[NSMutableDictionary alloc]init];
if (social) {
for (int i = 0 ; i < ABMultiValueGetCount(social); i++) {
NSDictionary *socialDict = (NSDictionary *)ABMultiValueCopyValueAtIndex(social, i);
NSString *twitterid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceTwitter]) {
twitterid = (NSString*)socialDict[@"username"];
[dict_social setValue:twitterid forKey:@"Twitter"];
}
NSString *facebookid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceFacebook]) {
facebookid = (NSString*)socialDict[@"username"];
[dict_social setValue:facebookid forKey:@"Facebook"];
}
NSString *linkedinid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceLinkedIn]) {
linkedinid = (NSString*)socialDict[@"username"];
[dict_social setValue:linkedinid forKey:@"LinkedIn"];
}
NSString *gamecenterid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceGameCenter]) {
gamecenterid = (NSString*)socialDict[@"username"];
[dict_social setValue:gamecenterid forKey:@"GameCenter"];
}
NSString *myspaceid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceMyspace]) {
myspaceid = (NSString*)socialDict[@"username"];
[dict_social setValue:myspaceid forKey:@"MySpace"];
}
NSString *flickerid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceFlickr]) {
flickerid = (NSString*)socialDict[@"username"];
[dict_social setValue:flickerid forKey:@"Flicker"];
}
[socialDict release];
}
CFRelease(social);
}
NSString *dictsocialstring = [NSString stringWithFormat:@"%@",dict_social];
if (!([dictsocialstring isEqualToString:@"(null)"]|| dictsocialstring == nil || dictsocialstring.length <4))
{
[dict setValue:dict_social forKey:@"SocialNetworks"];
}
[dict_social release];
// Getting Other Fields from address book
NSMutableDictionary *dict_others = [[NSMutableDictionary alloc]init];
if (!([company_name isEqualToString:@"(null)"]||company_name == nil || company_name.length ==0)) {
[dict_others setValue:company_name forKey:@"CompanyName"];
}
if (!([job_title isEqualToString:@"(null)"]||job_title == nil || job_title.length ==0)) {
[dict_others setValue:job_title forKey:@"JobTitle"];
}
if (!([birthday isEqualToString:@"1-1-2001"]||[birthday isEqualToString:@"(null)"]||birthday == nil || birthday.length ==0)) {
[dict_others setValue:birthday forKey:@"BirthDay"];
}
NSString *dictothersstring = [NSString stringWithFormat:@"%@",dict_others];
if (!([dictothersstring isEqualToString:@"(null)"]|| dictothersstring == nil || dictothersstring.length <4))
{
[dict setValue:dict_others forKey:@"OtherInfo"];
}
[dict_others release];
[dict setValue:record_id forKey:@"RecordID"];
//This NSLog(@"Value for Dict is========= %@ =========",dict);
NSString *namedictionstring = [NSString stringWithFormat:@"%@",dict_name];
NSString *emaildictstring = [NSString stringWithFormat:@"%@",dict_email];
NSString *phonedictstring = [NSString stringWithFormat:@"%@",dict_phone];
// NSLog(@"name dict length= %d email dict length= %d phone dict length = %d",namedictionstring.length,emaildictstring.length,phonedictstring.length);
// [array_addressbook addObject:dict];
if (phonedictstring.length >3) {
[arraytemp addObject:dict];
}
else
{
if (emaildictstring.length>3 && namedictionstring.length) {
[arraytemp addObject:dict] ;
}
else
{
NSLog(@"Contact is not valid= %@",dict_name);
}
}
[dict_name release];
[dict_phone release];
[dict_email release];
[dict release];
[company_name release];
[job_title release];
/* CFRelease(firstName);
CFRelease(midname);
CFRelease(lastName);
CFRelease(jobtitle);
CFRelease(birthday_c);
CFRelease(companyname);*/
// }
}
}
NSString *json_array_string = [arraytemp JSONRepresentation];
[IntoochUtil current_function_name:@"Inside getcontactdetails - End"];
NSLog(@"Json String To send= %@",json_array_string);
if (allSources) {
CFRelease(allSources);
}
if (addressBook) {
CFRelease(addressBook);
}
}
else
{
NSLog(@"This is empty.... nothing to perform");
NSMutableArray *arrayofdeletedpeoples= [[NSMutableArray alloc]init];
ABAddressBookRef addressbook = ABAddressBookCreate();
CFArrayRef allPeoples= ABAddressBookCopyArrayOfAllPeople(addressbook);
NSMutableArray *arrayofrecordIDCallback = [[NSMutableArray alloc]init];
int count = CFArrayGetCount(allPeoples);
for (int i =0; i<count; i++) {
ABRecordRef aSource = CFArrayGetValueAtIndex(allPeoples,i);
NSString * recordid = [NSString stringWithFormat:@"%d",ABRecordGetRecordID(aSource)];
[arrayofrecordIDCallback addObject:recordid];
}
NSLog(@"arrayofrecordIDCallback = %@ and count= %d",arrayofrecordIDCallback,[arrayofrecordIDCallback count]);
NSMutableArray *arrayofallrecordids = [userdefs valueForKey:@"AllRecordIDSBackGround"];
NSLog(@"arrayofallrecordids= %@ and count= %d",arrayofallrecordids,[arrayofallrecordids count]);
for (int i=0 ; i< [arrayofallrecordids count]; i++) {
if ([arrayofrecordIDCallback containsObject:[arrayofallrecordids objectAtIndex:i]]) {
}
else
{
[arrayofdeletedpeoples addObject:[arrayofallrecordids objectAtIndex:i]];
}
}
NSLog(@"Array of deleted peoples= %@",arrayofdeletedpeoples);
[arrayofdeletedpeoples release];
[arrayofallrecordids release];
[arrayofrecordIDCallback release];
if (allPeoples) {
CFRelease(allPeoples);
}
if (addressbook) {
CFRelease(addressbook);
}
}
//-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
[changedrecords release];
[userdefs release];
[arraytemp release];
NSLog(@"Ends Process");
NSTimeInterval timeStamptwo = [[NSDate date] timeIntervalSince1970];
NSNumber *timeStamptwoObj = [NSNumber numberWithDouble: timeStamptwo];
NSLog(@"Time Difference= %d",[timeStamptwoObj intValue]-[timeStamponeobj intValue]);
}
答案 1 :(得分：3)
是的，确实无法获得有关电话簿更改的特定通知。在回调通知触发时，您需要同步数据。
void MyAddressBookExternalChangeCallback (ABAddressBookRef ntificationaddressbook,CFDictionaryRef info,void *context)
{
NSLog(@"Changed Detected......");
// synch data
}
像viber，tango，watsapp这样的应用程序也做同样的事情，但在后台线程。
如果应用程序被终止，那么您需要在应用程序启动时同步数据，如didFinishLaunchingWithOptions中所示。
答案 2 :(得分：2)
据我所知，你不知道有什么区别 - 我自己也遇到了这个问题。
我的解决方案是：
我有一个基于本地核心数据的地址簿，每次收到此通知时，我都会运行一个同步数据的后台线程，并最终通知所有更改。
答案 3 :(得分：2)
在第一次，我使用sqlite转储本地数据库中的所有数据，然后在外部更改我从sqlite中的虚拟数据库中的联系人数据库转储新数据，然后根据已更改的内容触发大长比较查询。在我们的案例中，主要关注的是电话号码和姓名。一旦你在sqlite中的contacts db中获得更新更新。 我认为甚至whatsapp也在做类似的事情。我检查了whatsapp反映变化的时间，我们的应用程序几乎相似。实际上，我的应用程序在反映变化方面比whatsapp快2秒。 希望这会有所帮助。