Read, ReadText, Write, and WriteText Methods Example (VB)

Microsoft ActiveX Data Objects (ADO)

ADO 2.5 Samples

Read, ReadText, Write, and WriteText Methods Example (VB)

This example demonstrates how to read the contents of a text box into both a text Stream and a binary Stream. Other properties and methods shown include Position, Size, Charset, and SetEOS.

'BeginReadVB
Private Sub cmdRead_Click()
    On Error GoTo ErrorHandler
    
    'Declare variables
    Dim objStream As Stream
    Dim varA As Variant
    Dim bytA() As Byte
    Dim i As Integer
    Dim strBytes As String
    
    'Instantiate and Open Stream
    Set objStream = New Stream
    objStream.Open
    
    'Write the text content of a textbox to the stream
    If Text1.Text = "" Then
        Err.Raise 1, , "The text field is blank."
    End If
    objStream.WriteText Text1.Text
    
    'Display the text contents and size of the stream
    objStream.Position = 0
    Debug.Print "Default text:"
    Debug.Print objStream.ReadText
    Debug.Print objStream.Size
    
    'Switch character set and display
    objStream.Position = 0
    objStream.Charset = "Windows-1252"
    Debug.Print "New Charset text:"
    Debug.Print objStream.ReadText
    Debug.Print objStream.Size
    
    'Switch to a binary stream and display
    objStream.Position = 0
    objStream.Type = adTypeBinary
    Debug.Print "Binary:"
    Debug.Print objStream.Read
    Debug.Print objStream.Size
    
    'Load an array of bytes with the text box text
    ReDim bytA(Len(Text1.Text))
    For i = 1 To Len(Text1.Text)
        bytA(i - 1) = CByte(Asc(Mid(Text1.Text, i, 1)))
    Next
    
    'Write the buffer to the binary stream and display
    objStream.Position = 0
    objStream.Write bytA()
    objStream.SetEOS
    objStream.Position = 0
    Debug.Print "Binary after Write:"
    Debug.Print objStream.Read
    Debug.Print objStream.Size
    
    'Switch back to a text stream and display
    Debug.Print "Translated back:"
    objStream.Position = 0
    objStream.Type = adTypeText
    Debug.Print objStream.ReadText
    Debug.Print objStream.Size
    
    ' clean up
    objStream.Close
    Set objStream = Nothing
    Exit Sub
    
ErrorHandler:
    ' clean up
    If Not objStream Is Nothing Then
        If objStream.State = adStateOpen Then objStream.Close
    End If
    Set objStream = Nothing
    
    If Err <> 0 Then
        MsgBox Err.Source & "-->" & Err.Description, , "Error"
    End If
End Sub
'EndReadVB

See Also

Charset Property | Position Property | Read Method | ReadText Method | SetEOS Method | Size Property (ADO Stream) | Stream Object | Write Method | WriteText Method

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