ios - 应用程序在完成处理程序中崩溃并出现 EXC_BAD_ACCESS 错误

Question

任何人都可以帮我修复我的 API 调用功能吗？我解析数据并将其存储在结果中，如果解析时出现任何错误，我会抛出失败 json 错误。如果解析成功，那么我将数据保存在数据库中。但是在 json 解析失败后我的应用程序在这一行崩溃了

 return completion(.failure(.jsonError("Values of expenses not found")))

这是我的整个功能:-

func loadExpenseOfReport(organizationID: Int, reportID: Int, completion: @escaping (Result) -> Void) {

   self.remote.loadExpensesOfReport(organizationID, reportID: reportID) { result  in
       switch result {

       case .success(let json):
           var result : (json: [[String: Any]], ids: [Int])
           do {
               result = try Expense.processExpenses(JSON: json!, organizationID: Int(self.user.organization.organizationID))
           } catch let error {
               return completion(.failure(.jsonError("Values of expenses not found"))) // App crashes here
           }
           print("result \(result)")
           // Save in database
        self.dataStack.enqueueCoreDataBlock({ context in
               Sync.changes(result.json, inEntityNamed: "Expense", predicate: nil, parent: nil, parentRelationship: nil, inContext: context, operations: .all, completion: { error in
                   guard error == nil else {
                       return completion(.failure(.syncError(error!)))
                   }
                   return completion(.success(nil))
               })
           })
           //return completion(.success(nil))

       case .failure(let error):
           return completion(.failure(error))
       }
   }

但是当我将上面保存在数据库中的行更改为此时，它不再崩溃。

//self.dataStack.enqueueCoreDataBlock({ context in
           Sync.changes(result.json, inEntityNamed: "Expense", predicate: nil, parent: nil, parentRelationship: nil, inContext: self.dataStack.viewContext, operations: .all, completion: { error in
               guard error == nil else {
                   return completion(.failure(.syncError(error!)))
               }
               return completion(.success(nil))
           })
       //})

Answer 1

您不需要“返回”完成 block 。就像这样调用它:

var result : (json: [[String: Any]], ids: [Int])
           do {
               result = try Expense.processExpenses(JSON: json!, organizationID: Int(self.user.organization.organizationID))
           } catch let error {
               completion(.failure(.jsonError("Values of expenses not found")))
           }