NSPredicate 与 AND OR 和 NOT 条件

Created: November-22, 2018

通过使用为给定谓词提供基本布尔运算符的 NSCompoundPredicate 类，条件谓词将更清晰，更安全。

Objective-C

和 - 条件

  NSPredicate *predicate = [NSPredicate predicateWithFormat:@"samplePredicate"];
  NSPredicate *anotherPredicate = [NSPredicate predicateWithFormat:@"anotherPredicate"];
  NSPredicate *combinedPredicate = [NSCompoundPredicate andPredicateWithSubpredicates: @[predicate,anotherPredicate]];

或 - 条件

 NSPredicate *predicate = [NSPredicate predicateWithFormat:@"samplePredicate"];
 NSPredicate *anotherPredicate = [NSPredicate predicateWithFormat:@"anotherPredicate"];
 NSPredicate *combinedPredicate = [NSCompoundPredicate orPredicateWithSubpredicates: @[predicate,anotherPredicate]];

不 - 条件

 NSPredicate *predicate = [NSPredicate predicateWithFormat:@"samplePredicate"];
 NSPredicate *anotherPredicate = [NSPredicate predicateWithFormat:@"anotherPredicate"];
 NSPredicate *combinedPredicate = [NSCompoundPredicate notPredicateWithSubpredicate: @[predicate,anotherPredicate]];