实现上述功能的VB程序如下,但加框处代码有错,请改正。
Const n = 10 ‘数组元素的总数
Dim a(1 To n) As Integer
Private Sub Form_Load()
‘该过程对数组a进行赋值,并在列表框List1中显示,代码略
End Sub
Private Sub Command1_Click()
Dim i As Integer, j As Integer,flag(1 To n) As Boolean
‘flag(i)记录第i个元素是否重复出现
For i = 1 To n ‘flag(i)=true开始假设都只出现1次
flag(i) = True
Next i
For i = 1 To n
If flag(i) Then
For j = i + 1 To n
If Then flag(i) = False: flag(j) = False ‘①
Next j
End If
Next i
For i = 1 To n
If Then List2.AddItem Str(a(i)) ‘②
Next i
End Sub
① ②
当前状态下,先执行“删除”操作,然后插入10秒静音后直接保存,则该音频文件的大小约为( )
编写解密的VB程序,功能如下:在文本框Text1中输入密文,单击“解密”按钮Command1,在文本框Text2中显示去重后的文本,并在标签Label1中显示明文。程序运行界面如下图所示。
Private Sub Command1_Click()
Dim s1 As String, s2 As String, c As String, mw As String
Dim i As Integer
s1 = Text1.Text
s2 = Mid(s1, 1, 1)
For i = 2 To
c = Mid(s1, i, 1)
If c >= "A" And c <= "Z" Then
If Then s2 = s2 + c
Else
s2 = s2 + c
End If
Next i
mw = " "
i = 6
Do While i <= Len(s2)
mw = mw+Mid(s2, i, 1)
Loop
Text2.Text = s2
Label1.Caption = mw
End Sub
①能够存储大量数据,且占用空间少
②管理操作方便数据维护简单安全
③检索统计准确迅速高效
④数据维护较复杂
⑤数据应用共享性能好
数据库文件“stud. accdb”信息如图所示。
程序界面如图所示,左边列表框List1中显示所有学生信息(包括编号和完成次数),单击“排序”按钮(Command),所有编号按照作业完成次数从高到低显示在列表框List2中。
代码如下:
Dim conn As New ADODB. Connection
Dim rs As New ADODB. Recordset
Dim n As Integer
Dim a(500)As String
Dim b(500)As Integer
Private Sub Fom Load()
Dim i As Integer
conn. Connection String="Provider=Mi-crosoft. AC
A.OLEDB. 12.0;DATA Source="& App. Path &"\stud. accdb"
conn Open
Set rs. Active Connection=conn
rs. Open "Select*From info"
n=0
Do While not rs.EOF '到记录集最后一条记录后退出循环
n=n+1
a(n)=rs. fields("id")
b(n)=rs. fields("finshed")
rs. MoveNext '移动到下一条记录
Loop
For i=1 To n
List1. AddItem a(i)+" "+Str(b(i))
Next i
rs. Close
conn. Close
Set rs= Nothing
Set conn= Nothing
End sub
Private Sub Command1_Click()
Dim i As Integer, j As Integer, t1 As Integer, t2 As String, k As Integer
For i=1 To n-1 'n表示学生总数
k=i 'k保存第i大的数,一开始假定是a(i)
For j=i+1 To n
If b(k)<b(j) Then k=j '比较完成数
①
If ② Then
t1=b(i): b(i)=b(k): b(k)=t1 '交换完成次数
t2=a(i): a(i)=a(k): a(k)=t2 '交换编号
End If
Next j
Next i
For i=1 To n '在列表框List2中输出排序结果
Listt2. Addltem a(i)+" "+Str(b(i))
Next i
End sub
List1.pop(3)
print(list1) 的值为( )
下列关于“台风”数据表的描述,正确的是( )