Reading and Writing CLOB column in oracle by asp.net

Imports Oracle.DataAccess.Client
Imports Oracle.DataAccess.Types

Public Sub ReadLOBData()
Dim con As New OracleConnection(connectionstring)
con.Open()
Dim sql As String = "Select Mft_Text from Tab_Manifestation where Mft_Id=2"
Dim cmd As OracleCommand = New OracleCommand(sql, con)
Dim dr As OracleDataReader = cmd.ExecuteReader()
dr.Read()
Dim blob As OracleClob = dr.GetOracleClob(0)
txtManifest.Text = blob.Value
blob.Close()
dr.Close()
con.Close()
End Sub

Public Sub WriteLOBData()
Dim connection As New OracleConnection(connectionstring)
connection.Open()

Dim strSQL As String = "INSERT INTO TestCLOB (ID,CLOBTEXTFIELD) VALUES (1,:TEXT_DATA) "
'Dim strsql As String = "UPDATE TestCLOB SET CLOBTEXTFIELD=:TEXTDATA where testid=1"
Dim paramData As New OracleParameter
paramData.Direction = ParameterDirection.Input
paramData.OracleDbType = OracleDbType.Clob
paramData.ParameterName = "TEXT_DATA"
paramData.Value = txtInput.Text

Dim cmd As New OracleCommand
cmd.Connection = connection
cmd.Parameters.Add(paramData)
cmd.CommandText = strSQL
cmd.ExecuteNonQuery()

paramData = Nothing
cmd = Nothing
connection.Close()
End Sub