程序代码：

Option Explicit
Dim Change As Integer  '全局变量

Private Sub Form_Load()
Change = 0   '程序启动时定义初始值
End Sub

Private Sub Text1_Change()

 If Len(Text1) > 4 Then
     Timer1.Enabled = True
     Timer1.Interval = 100
     Change = Change + 1   '每写一次就+1，用于区别文件，当然你也可以使用Now来代替这个变量。
  End If
End Sub

Private Sub Timer1_Timer()

 Open App.Path & "\" & Change & ".txt" For Output As #1  '以全局变量为文件名进行Text1的信息保存
    Print #1, Text1

 Close #1

 Text1 = ""

 Timer1.Enabled = False

 End Sub

[此贴子已经被作者于2016-12-26 09:51编辑过]

程序代码：

Dim SS As Integer

Private Sub Form_Load()
SS = 0   '初始化变量
End Sub

Private Sub Text1_LostFocus()

 If Len(Text1.Text) > 4 Then
     SS = SS + 1
      Open App.Path & "\" & SS & ".txt" For Append As #1   'Append 是追加方式
      Write #1, Text1.Text    'Write方法是写入数据
       Close #1
       Text1.Text = ""
  End If
End Sub

'不需要Timer1控件程序更简单

[此贴子已经被作者于2017-1-13 09:13编辑过]