dotConnect for Oracle Documentation
Devart.Data.Oracle Namespace / OracleLob Class / CanWrite Property
Example

In This Topic
    CanWrite Property (OracleLob)
    In This Topic
    Gets a value indicating whether the OracleLob object supports writing.
    Syntax
    'Declaration
     
    Public Overrides ReadOnly Property CanWrite As Boolean
    public override bool CanWrite {get;}

    Property Value

    true if the OracleLob stream can be written; false if a OracleLob is closed, disposed or Null.
    Remarks
    Use this property to determine whether you can write to the instance of OracleLob class.
    Example
    static void ReverseBlob() 
    { 
            byte[] byteArray = { (byte)'A', (byte)'B', (byte)'C' }; 
            OracleLob blobFrom = new OracleLob(OracleDbType.Blob);
            blobFrom.Write(byteArray, 0, byteArray.Length);
            //blobFrom.ToString() = "ABC" 
    
            OracleLob blobTo = new OracleLob(OracleDbType.Blob); 
            ........
            //reverse OracleLob 
            if (blobFrom.CanSeek && blobFrom.CanRead && blobTo.CanWrite) 
                    for (blobFrom.Seek(-1, System.IO.SeekOrigin.End); ;blobFrom.Position -= 2) 
                    { 
                            blobTo.WriteByte((byte)blobFrom.ReadByte()); 
                            if (blobFrom.Position == 1) break; 
                    } 
            //blobTo.ToString() = "CBA"; 
    }
    Private Sub ReverseBlob()
            Dim byteArray As Byte() = New Byte() {AscW("A"c), AscW("B"c), AscW("C"c)}
            Dim blobFrom As New OracleLob(OracleDbType.Blob)
            blobFrom.Write(byteArray, 0, byteArray.Length)
            ' blobFrom.ToString() = "ABC"
    
            Dim blobTo As New OracleLob(OracleDbType.Blob)
            ........
            ' reverse OracleLob
            If ((blobFrom.CanSeek AndAlso blobFrom.CanRead) AndAlso blobTo.CanWrite) Then
                    blobFrom.Seek(CLng(-1), System.IO.SeekOrigin.End)
                    Do While True
                            blobTo.WriteByte(CByte(blobFrom.ReadByte))
                            If (blobFrom.Position = 1) Then
                                    Return
                            End If
                            blobFrom.Position = blobFrom.Position - 2
                    Loop
            End If
            ' blobTo.ToString() = "CBA";
    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