Read, ReadText, Write et WriteText, méthodes – Exemple (VB)

S’applique à : Access 2013, Office 2013

Cet exemple montre comment lire le contenu d'une zone de texte dans un objet Stream de texte et un objet Stream binaire. Les autres propriétés et méthodes illustrées incluent Position, Size, Charset et 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