[说明]
字符组合：程序界面如图示，在文本框Text1中输入若干个任意字符，单击“颠倒”按钮，将这些字符按相反的顺序显示在标签Lable1 中，并在标签Labs1 2处显示字符的个数。例如：输入abcabc2，显示为 2cbabca，组成字符数为4。

[Visual Basic 代码]
Private Sub cmdshow_ Click (
Dim n As Integer
Dim I As Integer
Dim str1 As String
N=Len ( Text1.Text )
For I=n To Step- 1
Str1= (1)
Next I
Labe11. Caption=Str1
End Sub
Private Sub cmdcount_ Click ( )
Dim n As Integer
Dim in As Integer
Dim i As Integer
Dim j As Integer
Dim flag As Integer
Dim str1 As Integer
Dim str2 As Integer
N= (2)
Str1 =Mid＄ ( Text1.Text, i. 1
For I =2 To n
Str2=mid＄ ( Text1,Text,I,1
M=Len (str1)
(3)
For j=1 To m
If (4) Then flag= 1; Exit For
Next j
If flag＜＞1 then str1=str1& str2
Next I
Lable2.Caption= (5)
End Sub