阅读加密数据库不适用于iOS 10

我正在开发一个 iOS 应用程序。 加密& 解密读取&写入正在工作，直到 iOS 9 。但是，升级到 iOS 10 后，它开始提供以下消息，即文件被加密或不是数据库。

I'm working on an iOS application. Encryption & Decryption to read & write was working till iOS 9. But after upgrade to iOS 10 it started to giving issue with following message that "file is encrypted or is not a database".

对于 DB加密我使用以下代码：

sqlite3 *db1;
if (sqlite3_open([[self.databaseURL path] UTF8String], &db1) == SQLITE_OK) {
const char* key = [@"strong" UTF8String];
sqlite3_key(db1, key, (int)strlen(key));

   if (sqlite3_exec(db1, (const char*) "SELECT count(*) FROM sqlite_master;", NULL, NULL, NULL) == SQLITE_OK) {
      NSLog(@"Password is correct, or a new database has been initialized");
   } else {
      NSLog(@"Incorrect password!");
   }
  sqlite3_close(db1);
}

&它的工作完全正常。

& it's working perfectly fine.

对于开放阅读操作，我使用以下代码：

For opening and reading operation I'm using following code:

-(void)openDB
{
    NSString *docsDir;
    docsDir = [self getDirectoryPath];
    aPath = [docsDir stringByAppendingPathComponent: @"SQLITE_DEMO.sqlite"];
    dbpath = [aPath UTF8String];
}

阅读：

if (sqlite3_open(dbpath, &contactDBNew) == SQLITE_OK)
        {
            NSString querySQL = [NSString stringWithFormat:@"SELECT  FROM USER"];

            const char *query_stmt = [querySQL UTF8String];
            char *err;

            int check = sqlite3_exec(contactDBNew, query_stmt, NULL, NULL, &err);

            if (sqlite3_prepare_v2(contactDBNew, query_stmt, -1, &statement, NULL) == SQLITE_OK)
            { 
                 // Successfully executed.
         } else {
              // Error in execution.
        }
  }

在阅读准备声明时，

Here it get failed while reading prepared statement with following error message: "file is encrypted or is not a database".

请指出我错过了什么！