Setting the Top Line in VB6 RichTextBox

Sean Hannity

2 min read

·

09-11-2024

6

0

Share

In Visual Basic 6 (VB6), the RichTextBox control is a powerful tool that allows developers to work with rich text formats. One useful feature is the ability to set the top line of the RichTextBox. This can be particularly important when you want to control the view of the text within the control.

Understanding RichTextBox

The RichTextBox control in VB6 provides the ability to display and edit formatted text, which includes various fonts, colors, and styles. It is often used in applications that require text formatting, such as word processors or note-taking applications.

Setting the Top Line

To set the top line of a RichTextBox in VB6, you can use the SelStart property in conjunction with the SelLength property. Here's how you can achieve this:

Example Code

Private Sub Form_Load()
    ' Load some sample text into the RichTextBox
    RichTextBox1.Text = "Line 1" & vbCrLf & _
                        "Line 2" & vbCrLf & _
                        "Line 3" & vbCrLf & _
                        "Line 4" & vbCrLf & _
                        "Line 5"
    
    ' Set focus to RichTextBox
    RichTextBox1.SetFocus
    
    ' Scroll to the second line
    SetTopLine 2
End Sub

Private Sub SetTopLine(ByVal lineNumber As Long)
    Dim topLinePos As Long
    Dim currentLine As Long
    
    ' Get the position of the line
    topLinePos = RichTextBox1.GetLineStart(lineNumber) ' Get starting position of the line
    
    ' Set the selection to the desired position to scroll
    RichTextBox1.SelStart = topLinePos
    RichTextBox1.SelLength = 0
    
    ' Ensure the RichTextBox is updated
    RichTextBox1.ScrollCaret
End Sub

Explanation

• Setting the Text: In the Form_Load event, some sample text is added to the RichTextBox.
• Scrolling to a Specific Line: The SetTopLine subroutine takes a line number as an argument. It retrieves the start position of that line using GetLineStart and sets the SelStart property to that position.
• Scrolling the Caret: The ScrollCaret method is then called to ensure that the RichTextBox scrolls to show the selected line.

Summary

Setting the top line in a VB6 RichTextBox is straightforward. By manipulating the selection properties of the control, you can control which line is displayed at the top, enhancing the user experience in text-heavy applications. With the example provided, you can easily integrate this functionality into your VB6 projects.