Option Control (VBCCROption)

VBCCROption 控件是一个单选按钮控件，用于在一组选项中选择一个选项。它通常与其他 Option 控件一起使用，形成一个选项组。

属性

关键属性

• Value: 是否选中
• Caption: 显示的文本
• Alignment: 文本对齐方式
• Enabled: 启用/禁用控件
• BackColor: 背景颜色
• ForeColor: 文本颜色
• Font: 字体设置
• Group: 分组设置
• TabStop: 是否可以通过Tab键获得焦点
• ToolTipText: 工具提示文本

方法

主要方法

• SetFocus(): 设置焦点到控件
• Refresh(): 刷新显示

事件

• Click(): 点击时触发
• GotFocus(): 获得焦点时触发
• LostFocus(): 失去焦点时触发
• MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
• MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
• KeyDown(KeyCode As Integer, Shift As Integer)
• KeyUp(KeyCode As Integer, Shift As Integer)

代码示例

基本用法

Private Sub Form_Load()
    ' 设置选项组
    With optGender(0)
        .Caption = "男"
        .Value = True
        .Tag = "M"
    End With
    
    With optGender(1)
        .Caption = "女"
        .Value = False
        .Tag = "F"
    End With
End Sub

选项组处理

Private Sub HandleOptionGroup()
    Dim i As Integer
    
    ' 获取选中的选项
    For i = 0 To optGender.Count - 1
        If optGender(i).Value Then
            Debug.Print "选中的性别: " & optGender(i).Tag
            Exit For
        End If
    Next i
End Sub

动态创建选项

Private Sub CreateOptions()
    Dim i As Integer
    Dim Top As Integer
    
    Top = 20
    
    ' 动态创建选项
    For i = 0 To 4
        With Controls.Add("VBCCROption", "optChoice" & i)
            .Left = 20
            .Top = Top
            .Caption = "选项 " & (i + 1)
            .Tag = i + 1
            Top = Top + 30
        End With
    Next i
End Sub

常见用例

设置对话框

Private Sub SetupSettingsDialog()
    ' 显示模式选项
    With fraDisplayMode
        .Caption = "显示模式"
        
        With optDisplay(0)
            .Caption = "简单模式"
            .Value = True
        End With
        
        With optDisplay(1)
            .Caption = "高级模式"
        End With
        
        With optDisplay(2)
            .Caption = "专家模式"
        End With
    End With
End Sub

Private Sub optDisplay_Click(Index As Integer)
    Select Case Index
        Case 0 ' 简单模式
            ShowSimpleControls
        Case 1 ' 高级模式
            ShowAdvancedControls
        Case 2 ' 专家模式
            ShowExpertControls
    End Select
End Sub

多组选项

Private Sub SetupMultipleGroups()
    ' 第一组 - 性别
    Frame1.Caption = "性别"
    optGender(0).Caption = "男"
    optGender(1).Caption = "女"
    
    ' 第二组 - 年龄段
    Frame2.Caption = "年龄段"
    optAge(0).Caption = "18岁以下"
    optAge(1).Caption = "18-30岁"
    optAge(2).Caption = "30岁以上"
End Sub

Private Sub GetSelectedOptions()
    Dim Gender As String
    Dim Age As String
    
    ' 获取性别选择
    If optGender(0).Value Then
        Gender = "男"
    Else
        Gender = "女"
    End If
    
    ' 获取年龄段选择
    For i = 0 To 2
        If optAge(i).Value Then
            Age = optAge(i).Caption
            Exit For
        End If
    Next i
    
    Debug.Print "选择: " & Gender & ", " & Age
End Sub

最佳实践

1. 分组管理

Private Sub ManageOptionGroups()
    ' 使用 Frame 控件来分组
    Frame1.Caption = "选项组 1"
    Frame2.Caption = "选项组 2"
    
    ' 确保每组只有一个选中项
    ValidateGroupSelection Frame1
    ValidateGroupSelection Frame2
End Sub

Private Sub ValidateGroupSelection(frm As Frame)
    Dim ctl As Control
    Dim HasSelection As Boolean
    
    HasSelection = False
    For Each ctl In frm.Controls
        If TypeOf ctl Is OptionButton Then
            If ctl.Value Then
                If HasSelection Then
                    ctl.Value = False
                Else
                    HasSelection = True
                End If
            End If
        End If
    Next ctl
    
    ' 如果没有选中项，选中第一个
    If Not HasSelection Then
        For Each ctl In frm.Controls
            If TypeOf ctl Is OptionButton Then
                ctl.Value = True
                Exit For
            End If
        Next ctl
    End If
End Sub

2. 错误处理

Private Function GetSelectedValue(ByVal GroupName As String) As Variant
    On Error GoTo ErrorHandler
    
    Dim ctl As Control
    
    For Each ctl In Me.Controls
        If TypeOf ctl Is OptionButton Then
            If ctl.Group = GroupName And ctl.Value Then
                GetSelectedValue = ctl.Tag
                Exit Function
            End If
        End If
    Next ctl
    
    GetSelectedValue = Null
    Exit Function
    
ErrorHandler:
    Debug.Print "选项获取错误: " & Err.Description
    GetSelectedValue = Null
End Function

已知问题和解决方案

1. 分组问题

Private Sub FixGroupingIssues()
    ' 使用 Frame 控件确保正确分组
    Frame1.Caption = "组1"
    Frame2.Caption = "组2"
    
    ' 将选项移动到对应的 Frame 中
    Set optGroup1(0).Container = Frame1
    Set optGroup1(1).Container = Frame1
    
    Set optGroup2(0).Container = Frame2
    Set optGroup2(1).Container = Frame2
End Sub

2. 焦点问题

Private Sub HandleFocusIssues()
    ' 确保可以通过键盘访问
    For i = 0 To optChoices.Count - 1
        optChoices(i).TabStop = True
        optChoices(i).TabIndex = i
    Next i
End Sub

其他提示

• 总是提供默认选择
• 使用清晰的标签文本
• 合理组织选项顺序
• 实现键盘导航
• 注意选项间距
• 提供视觉反馈
• 考虑可访问性
• 使用一致的样式
• 实现数据验证
• 在 Form_Unload 中清理资源

特殊用法

1. 创建三态选项

Private Sub CreateTriStateOptions()
    Dim States(2) As String
    States(0) = "启用"
    States(1) = "禁用"
    States(2) = "自动"
    
    For i = 0 To 2
        With Controls.Add("VBCCROption", "optState" & i)
            .Caption = States(i)
            .Left = 20
            .Top = 20 + (i * 30)
            .Tag = i
        End With
    Next i
End Sub

2. 创建图形选项

Private Sub CreateGraphicOptions()
    ' 创建带图标的选项
    With optViewMode(0)
        .Caption = "图标视图"
        Set .Picture = LoadPicture("icon_view.ico")
    End With
    
    With optViewMode(1)
        .Caption = "列表视图"
        Set .Picture = LoadPicture("list_view.ico")
    End With
End Sub

3. 创建动态选项组

Private Sub CreateDynamicOptionGroup(ByVal ParentFrame As Frame, _
                                   ByRef Choices() As String)
    Dim i As Integer
    Dim Top As Integer
    
    Top = 20
    
    For i = 0 To UBound(Choices)
        With Controls.Add("VBCCROption", "opt" & ParentFrame.Name & i)
            Set .Container = ParentFrame
            .Caption = Choices(i)
            .Left = 10
            .Top = Top
            .Tag = i
            If i = 0 Then .Value = True
            Top = Top + 25
        End With
    Next i
End Sub