GetUniBlob(String) Method

In This Topic

Gets the value of the specified column as a UniBlob object.

Syntax

Visual Basic
C#

'Declaration
 
Public Overloads Function GetUniBlob( _
   ByVal name As String _
) As UniBlob

public UniBlob GetUniBlob( 
   string name
)

Parameters

name: The name of the column to get value of.

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.

csharp

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();
  }
}

Visual Basic

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

Reference

UniDataReader Class
UniDataReader Members
Overload List
UniBlob Class

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