Private Sub Form_click()

        Image1．Picture = LoadPicture("1．jpg")

      End Sub

在程序运行时，能触发该事件的是（   ）

Private Sub Command1_Click()

  Dim x As Integer，Y As Long，st

As String

  For x=100 To 1 000

    y=x^2

    st=x&y         ‘将数字x和y合并成不含空格的数字串st

    If  Then               ‘①

       List1. AddItem Str(x)&"  "& Str(y)&"  "&st

    EndIf

  Next x

  End Sub

  Function judge(s As String)As Boolean

    Dim a(1 To 100)As String，i As Integer，j As Integer

    judge=False

    For i=1 To Len(s)

      a(i)=Mid(s，i，1)

    Next i

    For i=1 To Len(s)-1

      For j=i+1 To Len(s)

         If  Then Exit Function       ‘②

      Next j

    Next i

    judge=True

  End Function

当窗体Form1加载时，自动产生a、b数组的数据，并分别显示在列表框List1与List2中，单击合并按钮Command1后，在c数组中保存按规则合并后的a、b数组的数据，并显示在列表框List3中。程序截图如下所示：

实现该功能的VB程序如下：

Const m = 5

Const n = 6

Dim a(1 To m) As Integer

Dim b(1 To n) As Integer

Dim c(1 To m + n) As Integer

‘窗体加载时，生成数组a、b中的数据，并按要求排序后显示在列表框中，代码略

Private Sub Command1_Click()

Dim pa As Integer, pb As Integer, pc As Integer, s As Integer, flag As Boolean

pa = m: pb = 1: pc = 1

flag = True

Do While      ①     

  If a(pa) < b(pb) Then

    s = a(pa)

    pa = pa - 1

  Else

    s = b(pb)

    pb = pb + 1

  End If

  c(pc) = s

  If flag Then

    pc = m + n - pc + 1

  Else

    pc =

  End If

       ②     

Loop

‘处理a、b数组中剩余数据，并在列表框List3中输出数组c，代码略

End Sub