如何通过使用try和catch for xcode 7来转换此方法

Question

这是＆＃34; fetchData＆＃34;的代码。方法。我想将此代码实现到try - Catch块中。

如何更改。

 var error: NSError?

 if let fetchedResults = managedObjectContext.executeFetchRequest(fetchRequest, error: nil) as? [NSManagedObject]
 {
    //if not nil
    players = fetchedResults
 }
 else {
    println("could not fetch data \(error), \(error?.userInfo)")
 }

Answer 1

这是你可以做到的方式......

do {
     fetchedResults = try managedObjectContext.executeFetchRequest(fetchRequest)
      //Success....Do your stuff
} catch let error as NSError {
     //Failure ...catch error
     print("could not fetch data \(error), \(error?.userInfo)")
 }