代码:

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Option Explicit

Private Sub Command1_Click()
    Dim strTemp As String
    Dim strResult As String
    Dim strLen As Long
    Dim i  As Integer
    
    '假定是每次两个字符,算算到底有多少个
    strLen = Len(Text1.Text) / 2
    i = 1
    
    While i <= strLen
        '每次获取两个字符
        strTemp = Mid(Text1.Text, i, 2)
        
        '看看到底是属于那类的
        Select Case strTemp
            Case "B1"
                strResult = strResult + "88"
                
            Case "B2"
                strResult = strResult + "99"
            
            Case "B3"
                strResult = strResult + "00"
            
            Case "B4"
                strResult = strResult + "11"
        End Select
        i = i + 2
    Wend
    
    '全部获取完后就显示了
    Text2.Text = strResult
End Sub

Private Sub Form_Load()

    '测试之用
    Text1.Text = "B2B4B1B2B3B1B4B2"
End Sub

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