Mehrere sqlcommands zurückgeben

Question

Ich bekomme, dass wir using verwenden können, um mehrere Befehle in einem sqlconnection zu haben.

So:

using (SqlConnection connection = new SqlConnection(connectionString)) 
{ 
    connection.Open(); 
    using (SqlCommand command1 = new SqlCommand(commandText1, connection)) 
    { 
    } 
    using (SqlCommand command2 = new SqlCommand(commandText2, connection)) 
    { 
    } 
    // etc 
} 

Was aber, wenn die using in einem Verfahren, das einen Leser Besetzung zurückkehrt?

So:

public IEnumerable<LocationInfo> GetData() 
{   
    using (var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["Database"].ConnectionString)) 
    { 
     //connection.Close(); 
     connection.Open(); 
     using (SqlCommand command = new SqlCommand(@"SELECT .... ", connection)) 
     {   
      command.Notification = null; 
      SqlDependency dependency = new SqlDependency(command); 
      dependency.OnChange += new OnChangeEventHandler(dependency_OnChange); 

      if (connection.State == ConnectionState.Closed) 
      { connection.Open(); } 
      using (var reader = command.ExecuteReader()) 
      { 
       return reader.Cast<IDataRecord>().Select(x => new LocationInfo()       
       { 
        Names = x.GetString(2), 
        Values = Math.Round(x.GetDouble(7), 2).ToString("#,##0.00"), 
        ValuesDouble = x.GetDouble(7), 
        Values2 = Math.Round(x.GetDecimal(9), 2).ToString("#,##0.00"), 
        ValuesDouble2 = x.GetDecimal(9), 
        truckDelivery=x.GetDecimal(3), 
        truckIdle = x.GetDecimal(4), 
        truckRepair = x.GetDecimal(5), 
        truckReady = x.GetDecimal(6), 
        presentEmp=x.GetInt32(11), 
        absentEmp = x.GetInt32(12), 
        ondutyEmp = x.GetInt32(13), 
       }).ToList(); 
      } 
      /* I tried this but it just got ignored 
      using (var reader2 = command.ExecuteReader()) 
      { 
       reader2.NextResult(); 
       return reader2.Cast<IDataRecord>().Select(x => new LocationInfo() 
       { 
        SumVol = x.GetString(0)  
       }).ToList(); 
      }*/ 
     } 
    } 
} 

Helfen Sie mir bitte. Meine zweite using wird immer ignoriert und nicht davon ausgehen, dass ich etwas weiß, weil ich neu bin. Vielen Dank im Voraus.

Answer 1

Sie müssen den Datensatz lesen, auf den der von ExecuteReader erhaltene SqlDataReader zeigt. Akkumulieren Sie Ihre LocationInfo in einer Liste, und geben Sie sie zurück, wenn Sie die Schleife über den Reader beendet haben.

public IEnumerable<LocationInfo> GetData() 
{ 
    List<LocationInfo> locations = new List<LocationInfo>(); 
    using (var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["Database"].ConnectionString)) 
    using (SqlCommand command = new SqlCommand(@"SELECT .... ", connection)) 
    { 
     connection.Open(); 
     using (var reader = command.ExecuteReader()) 
     { 
      while(reader.Read()) 
      { 
       LocationInfo x = new LocationInfo() 
       { 
        Names = x.GetString(2), 
        Values = Math.Round(x.GetDouble(7), 2).ToString("#,##0.00"), 
        ValuesDouble = x.GetDouble(7), 
        Values2 = Math.Round(x.GetDecimal(9), 2).ToString("#,##0.00"), 
        ValuesDouble2 = x.GetDecimal(9), 
        truckDelivery=x.GetDecimal(3), 
        truckIdle = x.GetDecimal(4), 
        truckRepair = x.GetDecimal(5), 
        truckReady = x.GetDecimal(6), 
        presentEmp=x.GetInt32(11), 
        absentEmp = x.GetInt32(12), 
        ondutyEmp = x.GetInt32(13), 
       }; 
       locations.Add(x); 
      } 
     } 
    } 
    return locations; 

} 

Answer 2

OK also hier ist, was Sie in Ihrer Situation tun können, um Ergebnisse von zwei Ergebnismengen zu einem Objekt zusammenzuführen.

public IEnumerable<LocationInfo> GetData() 
{ 
     List<LocationInfo> locations = new List<LocationInfo>(); 
     using (var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["Database"].ConnectionString)) 
     using (SqlCommand command = new SqlCommand(@"SELECT .... ", connection)) 
     { 
      connection.Open(); 

      using (var reader = command.ExecuteReader()) 
      { 
       LocationInfo x = new LocationInfo(); 
       while(reader.Read()) 
       { 

        { 
         x.Names = reader.GetString(2), 
         x.Values=Math.Round(reader.GetDouble(7),2).ToString("#,##0.00"), 
         x.ValuesDouble = reader.GetDouble(7), 
         Values2 = Math.Round(reader.GetDecimal(9), 2).ToString("#,##0.00"), 
         x.ValuesDouble2 = reader.GetDecimal(9), 
         x.truckDelivery=reader.GetDecimal(3), 
         x.truckIdle = reader.GetDecimal(4), 
         x.truckRepair = reader.GetDecimal(5), 
         x.truckReady = reader.GetDecimal(6), 
         x.presentEmp=reader.GetInt32(11), 
         x.absentEmp = reader.GetInt32(12), 
         x.ondutyEmp = reader.GetInt32(13), 
        }; 

       } 
       if(reader.NextResult()) 
       { 
       while (reader.Read()) 
       { 
        x.SumVol=reader.GetString(0); 
       } 
       } 
       locations.Add(x); 
      } 
     } 
     return locations; 
}