17.小李編寫一個統(tǒng)計學生選考科目的VB程序,算法的基本思想是:檢查每位學生選課組合的編碼是否有效,對有效選擇結果進行科目統(tǒng)計,根據各科次占有效人數的百分率求出各科排名.程序運行時,單擊“顯示”按鈕Command1,學生選課數據顯示在列表框list1中,各科編號及對應科目名稱顯示列表框list2中,單擊“統(tǒng)計”按鈕Command2,選課結果按各科百分率由高到低顯示在列表框list3中,程序運行結果如圖所示.
實現上述功能的VB程序如下,請回答下列問題:
(1)學生選課的編碼數據存儲在數據表中,其字段名為
.
(2)請在橫線處填入合適的代碼.
Dim ach(1 to 500)As String’存儲各學生選課編碼
Dim bno(1 to 10)As Integer’存儲各科目編號
Dim bname (1 to 10)As String’存儲各科目名稱
Dim bnum(1 to 10)As Integer’存儲各科目被選次數
Dim bmc(1 to 10)As Integer’存儲各科目被選的名次
Dim n As Integer,num As Integer
Private Sub Commandl
-Click( ?。?br /> Dim i As Integer,km As String
km=“物理化學生物政治歷史地理技術“
Dim cn As New ADODB.Connection,rs As New ADODB.Recordset,spl As String
cn.Open“provider=Microsoft.oledb.4;Data Source=“+App.Path+“\students.mdb“
rs.Open“select*from choose“,cn
Do Whole Not rs.EOF
n=n+1:ach(n)=rs.Fields(“subject“):rs.MoveNext
Loop
rs.Close
cn.Close
Set rs=Nothing
Set cn=Nothing
For i=1 to 7
bno(i)=i
bname(i)=Mid(km,(i-1)*2+1,2)
List2.AddItem TR(bno(i))+“---“+bname(i)
Next i
End Sub
Private Sub Command2
-Click( ?。?br /> Dim i As Integer,j As Integer,k As Integer
Dim c As String,per As Integer
For i=1 to n
If check(ach(i))=True Then
For j=1 to 3
c=Mid(ach(i),j,1)
bnum(Val(c))=
Next j
num=num+1
End If
Next i
i=1
Do While i<=7’該循環(huán)得到各學科被選人數的名次
bmc(i)=1
For j=1 to 7
If bnum(j)>bnum(i) Then
Next j
i=i+1
Loop
For i=1 to 7
For j=1 to 7
If
Then
per=In(bnum(j)*100/num*100)/100
List3.AddItem Str(bno(j))+“---“+Str(per)+“%“
End If
Next i
End Sub
Function check(s As String) As Boolean
’代碼略!若學生選代碼有效,函數返回True,否則返回False
End Function.