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Devart.Data.Universal Namespace / UniDataReader Class / GetUniBlob Method / GetUniBlob(Int32) Method
The zero-based column ordinal.
Example

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    GetUniBlob(Int32) Method
    In This Topic
    Gets the value of the specified column as a UniBlob object.
    Syntax
    'Declaration
     
    Public Overloads Function GetUniBlob( _
       ByVal i As Integer _
    ) As UniBlob
    public UniBlob GetUniBlob( 
       int i
    )

    Parameters

    i
    The zero-based column ordinal.

    Return Value

    The value of the specified column as a UniBlob object.
    Example
    This example shows how to download a BLOB field from a table using GetUniBlob method.
    public void DownloadBlob(UniConnection myConnection)
    {
      UniCommand myCommand = new UniCommand("SELECT * FROM Test.Pictures", myConnection);
      myConnection.Open();
      UniDataReader myReader = myCommand.ExecuteReader(System.Data.CommandBehavior.Default);
      try
      {
        while (myReader.Read())
        {
          UniBlob myBlob = myReader.GetUniBlob(myReader.GetOrdinal("Picture"));
          if(!myBlob.IsNull)
          {
            string FN = myReader.GetString(myReader.GetOrdinal("PicName"));
            FileStream fs = new FileStream("D:\\Tmp\\"+FN+".bmp", FileMode.Create);
            BinaryWriter w = new BinaryWriter(fs);
            w.Write(myBlob.Value);
            w.Close();
            fs.Close();
            Console.WriteLine(FN+" downloaded.");
          }
        }
      }
      finally
      {
        myReader.Close();
        myConnection.Close();
      }
    }
    Public Sub DownloadBlob(ByVal myConnection As UniConnection)
      Dim myCommand As New UniCommand("SELECT * FROM Test.Pictures", myConnection)
      myConnection.Open()
      Dim myReader As UniDataReader = myCommand.ExecuteReader(System.Data.CommandBehavior.Default)
      Try
        While myReader.Read()
          Dim myBlob As UniBlob = myReader.GetUniBlob(myReader.GetOrdinal("Picture"))
          If Not myBlob.IsNull Then
            Dim FN As String = myReader.GetString(myReader.GetOrdinal("PicName"))
            Dim fs As FileStream = New FileStream("D:\Tmp\" + FN + ".bmp", FileMode.Create)
            Dim w As BinaryWriter = New BinaryWriter(fs)
            w.Write(myBlob.Value)
            w.Close()
            fs.Close()
            Console.WriteLine(String.Concat(FN, " downloaded."))
          End If
        End While
      Finally
        myReader.Close()
        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

    See Also