Classic Snippets That Still Teach

' The canonical first program (an event), a dialog, done.
Option Explicit

Private Sub Command1_Click()
    Dim userName As String
    userName = Trim(InputBox("Your name?", "VB Depot"))
    If Len(userName) = 0 Then Exit Sub
    MsgBox "Hello, " & userName & "!", vbInformation, "Welcome"
End Sub

Everything the language stood for is in these seven lines: behaviour attached to an event, a defensively trimmed input, an early exit instead of a nested branch, and a completed interaction with no ceremony. Note Option Explicit at the top, off by default in fresh VB6 projects, on by discipline in every professional codebase.

Private Sub ProcessFile(ByVal path As String)
    On Error GoTo Fail
    Dim fnum As Integer
    fnum = FreeFile
    Open path For Input As #fnum

    Do While Not EOF(fnum)
        Dim line As String
        Line Input #fnum, line
        ' ... handle the line ...
    Loop

Tidy:
    On Error Resume Next
    Close #fnum
    Exit Sub

Fail:
    MsgBox "Could not process file: " & Err.Description
    Resume Tidy
End Sub

On Error GoTo was much mocked, mostly by people who never read the second half of the pattern. The mature idiom pairs a handler with a cleanup section that the success path falls through and the failure path resumes into: an honest ancestor of try/finally, arrived at from the other direction. The goto was the flaw; the discipline was the point.

' Late binding: works with any installed Office version.
Dim xl As Object, wb As Object
Set xl = CreateObject("Excel.Application")
Set wb = xl.Workbooks.Add
xl.Visible = False

wb.Worksheets(1).Range("A1").Value = "Quarterly report"
wb.Worksheets(1).Range("A1").Font.Bold = True

wb.SaveAs App.path & "\report.xls"
wb.Close False
xl.Quit
Set wb = Nothing: Set xl = Nothing

The COM automation handshake, create, drive, close, quit, then release, anchored a thousand reporting systems and half of the VB6-to-Office bridge described in the VBA deep dive. The colon-joined Set … = Nothing pair at the end was superstition for most objects and vital practice for a few; every veteran could name the few.

Dim ctl As Control
For Each ctl In Me.Controls
    If TypeOf ctl Is TextBox Then
        ctl.Text = vbNullString
    End If
Next ctl

A form is a collection; the collection is enumerable; clearing every text box is four lines. This gentle treatment of containers is one of the design strains that survived intact into VB.NET, see the Great Split for what changed and what carried over, and into the daily practice of anyone who has ever written a loop over a spreadsheet's cells.