vb里面的对话框控件，打开“另存为”对话框后，单击取消选择不保存后还是会在目录保存文件

这个COM的对话框控件取消就是这样的机制，要判断用户点的是“取消”，就要设置控件的CancelError属性为True才可以接收到用户是否点了取消（这样真是增加了程序员的代码工作量），对了你的程序修改成这样就可以了：
On Error Resume Next

Dialog.Flags = &H4
Dialog.DefaultExt = ".txt"
Dialog.FilterIndex = 1
Dialog.CancelError = False
Dialog.ShowSave

If Err.Number = 0 Then
Open Dialog.FileName For Output As #1
Print #1, Text_List.Text
Close #1
End If 答案补充 有上的有误，下面的正确：
On Error Resume Next
Dialog.Flags = &H4
Dialog.DefaultExt = ".txt"
Dialog.FilterIndex = 1
Dialog.CancelError = True
Dialog.ShowSave

If Err.Number = 0 Then
Open Dialog.FileName For Output As #1
Print #1, Text_List.Text
Close #1
End If

Private Sub Command1_Click()
On Error GoTo ErrProc:
Dialog.Flags = &H4
Dialog.Filter = "*.txt"
Dialog.FilterIndex = 1
Dialog.CancelError = True
Dialog.ShowSave
Open "C:\Documents and Settings\11111\桌面\11.txt" For Output As #1
Print #1, Text1
Close #1
ErrProc:
End Sub 答案补充 Private Sub Command1_Click()
On Error GoTo ErrProc:
Dialog.Flags = &H4
Dialog.Filter = "*.txt"
Dialog.CancelError = True
Dialog.ShowSave
Open Dialog.FileName & ".txt" For Output As #1
Print #1, Text1
Close #1
ErrProc:
End Sub

把CancelError设置为True当点取消时会产生一个错误 在程序开头加上On Error GoTo Wrong:
在程序最后写上Wrong:就可以了