NextResult Method (MySqlDataReader)

In This Topic

Advances the data reader to the next result, when reading the results of batch SQL statements.

Syntax

Visual Basic
C#

'Declaration
 
Public Overrides Function NextResult() As Boolean

public override bool NextResult()

Return Value

true if there are more result sets; otherwise, false.

Remarks

Used to process multiple results, which can be generated by executing batch SQL statements.

By default, the MySqlDataReader is positioned on the first result.

You can determine what result is current using CurrentResult property. Total amount of results stored in MySqlDataReader is represented by ResultCount property.

Example

The following example shows how to use NextResult to iterate through set of results.

csharp

public void FetchResults(MySqlConnection myConnection)
{
  MySqlCommand cmd = new MySqlCommand("SELECT EmpNo, EName FROM Test.Emp;SELECT * FROM Test.Dept");
  cmd.FetchAll = true;
  cmd.Connection = myConnection;
  myConnection.Open();
  try
  {
    MySqlDataReader reader = cmd.ExecuteReader();
    Console.WriteLine("Quantity of results: " + reader.ResultCount);
    while (true)
    {
      Console.WriteLine("---------------Result number " + reader.CurrentResult);
      while (reader.Read())
      {
        Console.Write(reader.CurrentRecord);
        Console.Write("\t"+reader[0]);
        Console.WriteLine("\t"+reader[1]);
      }
    if (!reader.NextResult())
      {
        break;
      }
      Console.ReadLine();
    }
  }
  finally
  {
    myConnection.Close();
  }
}

Visual Basic

Public Sub FetchResults(ByVal myConnection As MySqlConnection)
  Dim cmd As MySqlCommand = New MySqlCommand("SELECT EmpNo, EName FROM Test.Emp;SELECT * FROM Test.Dept")
  cmd.FetchAll = True
  cmd.Connection = myConnection
  myConnection.Open()
  Try
    Dim reader As MySqlDataReader = cmd.ExecuteReader()
    Console.WriteLine(String.concat("Quantity of results: ", reader.ResultCount))
    While True
      Console.WriteLine(String.Concat("---------------Result number ", reader.CurrentResult))
      While reader.Read()
        Console.Write(reader.CurrentRecord)
        Console.Write(String.Concat(" ", reader(0)))
        Console.WriteLine(String.Concat(" ", reader(1)))
      End While
      If Not reader.NextResult() Then
        Exit While
      End If
      Console.ReadLine()
    End While
  Finally
    myConnection.Close()
  End Try
End Sub

Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

MySqlDataReader Class
MySqlDataReader Members
CurrentResult Property
ResultCount Property

Send Feedback