' This program required you to create a form containing
' a single text box, txtOutput, which must have Multiline
' set to True

' This code should be in your main form's source file
' (e.g. frmMain.frm)

Option Explicit
 Dim strName(50) As String
 Dim blankpos As Single
 Dim a As Single
 Dim strLast(50) As String
 Dim strFirst(50) As String
 Dim strTemp As String
 Dim flag As Boolean
 Dim i As Integer
 Dim l As Integer

Private Sub Form_Load()
    Open "test.dat" For Input As #1
        Do While Not EOF(1)
            ' read each line from file
            a = a + 1
            Line Input #1, strName(a)
                        
            ' get the first name and the last name
            blankpos = InStr(1, strName(a), " ")
            strLast(a) = Mid(strName(a), 1, blankpos - 1)
            strFirst(a) = Mid(strName(a), blankpos + 1, Len(strName(a)))
        Loop
    Close #1

    ' now sort the names by last name
    For i = 1 To a
        For l = a To 1 Step -1
            If strLast(l) > strLast(l + 1) Then
                ' swap the last names
                strTemp = strLast(l)
                strLast(l) = strLast(l + 1)
                strLast(l + 1) = strTemp
                
                ' swap the first names
                strTemp = strFirst(l)
                strFirst(l) = strFirst(l + 1)
                strFirst(l + 1) = strTemp
            End If
        Next l
    Next i

    ' print the names to the text box
    For l = 2 To a + 1
         txtOutput.Text = txtOutput.Text & (strFirst(l) & " " & strLast(l)) & vbCrLf
    Next l
End Sub