Mac Spotlight-API：如何搜索电子邮件的“收件人”、“发件人”或“主题”字段

Question

目前我有搜索电子邮件正文的 Spotlight-api 代码。我正在使用NSMetadataQuery 并为"kMDItemTextContent like[c] %@" 创建谓词。当请求的“搜索词”在电子邮件正文中时，这可以正常工作。

在 Spotlight 应用程序（右上角的放大镜图标）中，如果我输入“to: john”，我将获得“to”字段包含单词“john”的电子邮件列表（例如，某些电子邮件地址的一部分 john@something。 com)。

我尝试通过添加"kMDItemRecipients"、"kMDItemRecipientEmailAddresses"、"kMDItemAuthors"、"kMDItemAuthorEmailAddresses" 和"kMDItemSubject" 类型的附加谓词来使用[NSCompoundPredicate orPredicateWithSubpredicates:] 实现此目的。 不幸的是，这不会返回所需的电子邮件。

有谁知道如何使用 Spotlight-API 实现这一目标？

下面是我的代码：

NSString *predicateFormat = @"kMDItemTextContent like[c] %@";
NSPredicate *predicateToRun = [NSPredicate predicateWithFormat:predicateFormat, self.searchKey];

NSString *predicateFormat1 = @"kMDItemTitle like[c] %@";
NSPredicate *predicateToRun1 = [NSPredicate predicateWithFormat:predicateFormat1, self.searchKey];

NSString *predicateFormat2 = @"kMDItemAuthorEmailAddresses like[c] %@";
NSPredicate *predicateToRun2 = [NSPredicate predicateWithFormat:predicateFormat2, self.searchKey];

NSString *predicateFormat3 = @"kMDItemAuthors like[c] %@";
NSPredicate *predicateToRun3 = [NSPredicate predicateWithFormat:predicateFormat3, self.searchKey];

NSString *predicateFormat4 = @"kMDItemRecipientEmailAddresses like[c] %@";
NSPredicate *predicateToRun4 = [NSPredicate predicateWithFormat:predicateFormat4, self.searchKey];

NSString *predicateFormat5 = @"kMDItemRecipients like[c] %@";
NSPredicate *predicateToRun5 = [NSPredicate predicateWithFormat:predicateFormat5, self.searchKey];

NSString *predicateFormat6 = @"kMDItemSubject like[c] %@";
NSPredicate *predicateToRun6 = [NSPredicate predicateWithFormat:predicateFormat6, self.searchKey];

NSUInteger options = (NSCaseInsensitivePredicateOption|NSDiacriticInsensitivePredicateOption);
NSPredicate *compPred = [NSComparisonPredicate
                         predicateWithLeftExpression:[NSExpression expressionForKeyPath:@"*"]
                         rightExpression:[NSExpression expressionForConstantValue:self.searchKey]
                         modifier:NSDirectPredicateModifier
                         type:NSLikePredicateOperatorType
                         options:options];

predicateToRun = [NSCompoundPredicate orPredicateWithSubpredicates:
                     [NSArray arrayWithObjects:
                      compPred, 
                      predicateToRun, predicateToRun1, predicateToRun2, predicateToRun3, predicateToRun4,   
                      predicateToRun5, predicateToRun6, nil]];

predicateToRun = [NSCompoundPredicate andPredicateWithSubpredicates:
                  [NSArray arrayWithObjects:predicateToRun, [NSPredicate predicateWithFormat:@"(kMDItemContentType != 'public.vcard')"], nil]];

[self.query setPredicate:predicateToRun]; 

[self.query startQuery];

Answer 1

我知道如何使用 MDQuery 执行此操作 - 我认为这更简单。

您可以在命令行中使用与在 mdfind 中使用的基本相同的查询。

创建一个搜索字符串，例如：（未测试）

((((kMDItemAuthorEmailAddresses == "*john*"cd)) || ((kMDItemAuthors == "*john*"cd))) && (kMDItemContentType == 'com.apple.mail.emlx'))

也在终端 mdls /path/to/library/mail/v2/24324.emlx 将显示搜索电子邮件的内容。它是你的朋友

注意如何连接objective c 通知。

NSString* query = some string ;

MDQueryRef mdQuery = MDQueryCreate(nil, (CFStringRef)query, nil, nil);

// if something is goofy, we won't get the query back, and all calls involving a mil MDQuery crash. So return:
if (mdQuery == nil)
    return;

NSNotificationCenter* nf = [NSNotificationCenter defaultCenter];
[nf addObserver:self selector:@selector(progressUpradeQuery:) name:(NSString*)kMDQueryProgressNotification object:(id) mdQuery];
[nf addObserver:self selector:@selector(finishedUpradeQuery:) name:(NSString*)kMDQueryDidFinishNotification object:(id) mdQuery];
[nf addObserver:self selector:@selector(updatedUpradeQuery:) name:(NSString*)kMDQueryDidUpdateNotification object:(id) mdQuery];

// Should I run this query on the network too? Difficult decision, as I think that this will slow stuff way down.
// But i think it will only query leopard servers so perhaps ok
//MDQuerySetSearchScope(mdQuery, (CFArrayRef)[NSArray arrayWithObjects:(NSString*)kMDQueryScopeComputer, (NSString*)kMDQueryScopeNetwork, nil], 0);

// start it
BOOL queryRunning = MDQueryExecute(mdQuery, kMDQueryWantsUpdates); 
if (!queryRunning)
{
    CFRelease(mdQuery);
    mdQuery = nil;
    // leave this log message in...
    NSLog(@"MDQuery failed to start.");
    return;
}

汤姆