Swift 3語法錯誤（Backendless）

Question

更新我的Xcode後，我在backendless的find中收到錯誤語法例如

dataStore.find(
     { (result: BackendlessCollection!) -> Void in 
      let contacts = result.getCurrentPage() 
      for obj in contacts { 
       print("\(obj)") 
      } 
     }, 
     error: { (fault: Fault!) -> Void in 
      print("Server reported an error: \(fault)") 
    }) 

和錯誤是：Cannot convert value of type '(BackendlessCollection!) -> Void' to expected argument type '((BackendlessCollection?) -> Void)!'

如何解決它??? （！結果：BackendlessCollection）

Answer 1

與

dataStore?.find(
     { (result: BackendlessCollection?) -> Void in 
      let contacts = result?.getCurrentPage() 
      for obj in contacts! { 
       print("\(obj)") 

      } 
     }, 
     error: { (fault: Fault?) -> Void in 
      print("Server reported an error: \(fault)") 
    })