Dim i As Integer, s As String

i = 0

Do While i < 5

  s = Str(i) + s

  i = i + 1

Loop

程序界面如图所示，在文本框Text_1中输入原始字符串，在文本框Text_2中输入需要删除的字符，单击“删除此字符”按钮(Command1)后，在文本框Text_3中输出处理后的结果。

解决此问题的算法流程图如图所示，相应的Visual Basic程序如下：

Dim p As String,k As String

Private Sub Command1_Click()

Dim s As Integer,result As String,flag As Boolean

result=“”

p=Text_1.Text

k=Text_2.Text

For s=1 To Len(p)

  flag=f(s)

  If Not flag Then

   result=result+①   

  End If

Next s

②   

End Sub

Function f(s As Integer)As Boolean

  If Mid(p,s,1)=k Then f=True

End Function