RichTextBox Control (VBCCRRichTextBox)

VBCCRRichTextBox 控件是一个富文本编辑控件，支持多种文本格式、样式和图片。它提供了比标准文本框更强大的文本编辑和格式化功能。

属性

关键属性

• Text: 获取或设置纯文本内容
• RTFText: 获取或设置 RTF 格式文本
• SelText: 选中的文本
• SelStart: 选择的起始位置
• SelLength: 选择的长度
• SelColor: 选中文本的颜色
• SelBold: 选中文本是否加粗
• SelItalic: 选中文本是否斜体
• SelUnderline: 选中文本是否下划线
• MultiLine: 是否支持多行
• ScrollBars: 滚动条设置
• ReadOnly: 是否只读
• AutoURLDetect: 是否自动检测URL

方法

主要方法

• LoadFile(FileName As String): 加载文件
• SaveFile(FileName As String): 保存文件
• Find(Text As String): 查找文本
• Replace(Text As String): 替换文本
• Cut(): 剪切选中内容
• Copy(): 复制选中内容
• Paste(): 粘贴内容
• Undo(): 撤销操作
• Redo(): 重做操作

事件

• Change(): 内容改变时触发
• SelChange(): 选择改变时触发
• Click(): 点击时触发
• DblClick(): 双击时触发
• KeyDown(KeyCode As Integer, Shift As Integer)
• KeyPress(KeyAscii As Integer)
• KeyUp(KeyCode As Integer, Shift As Integer)
• LinkClick(ByVal URL As String): 点击链接时触发

代码示例

基本用法

Private Sub Form_Load()
    With RichTextBox1
        .MultiLine = True
        .ScrollBars = vbVertical
        .AutoURLDetect = True
        .Text = "欢迎使用富文本编辑器"
    End With
End Sub

文本格式化

Private Sub FormatText()
    With RichTextBox1
        ' 设置选中文本的格式
        .SelStart = 0
        .SelLength = 10
        .SelBold = True
        .SelColor = vbBlue
        
        ' 添加新文本并设置格式
        .SelStart = .TextLength
        .SelText = vbCrLf & "新段落"
        .SelItalic = True
        .SelColor = vbRed
    End With
End Sub

查找和替换

Private Sub FindAndReplace(ByVal FindText As String, _
                          ByVal ReplaceText As String)
    Dim StartPos As Long
    Dim FindLen As Long
    
    With RichTextBox1
        StartPos = 0
        FindLen = Len(FindText)
        
        Do
            StartPos = .Find(FindText, StartPos)
            If StartPos = -1 Then Exit Do
            
            .SelStart = StartPos
            .SelLength = FindLen
            .SelText = ReplaceText
            
            StartPos = StartPos + Len(ReplaceText)
        Loop
    End With
End Sub

常见用例

简单文本编辑器

Private Sub CreateTextEditor()
    ' 设置编辑器基本功能
    With RichTextBox1
        .MultiLine = True
        .ScrollBars = vbBoth
        .AutoURLDetect = True
        .HideSelection = False
    End With
    
    ' 添加工具栏
    With Toolbar1
        .Buttons.Add , "New", "新建"
        .Buttons.Add , "Open", "打开"
        .Buttons.Add , "Save", "保存"
        .Buttons.Add , , , tbrSeparator
        .Buttons.Add , "Cut", "剪切"
        .Buttons.Add , "Copy", "复制"
        .Buttons.Add , "Paste", "粘贴"
    End With
End Sub

Private Sub Toolbar1_ButtonClick(ByVal Button As MSComctlLib.Button)
    Select Case Button.Key
        Case "New"
            RichTextBox1.Text = ""
        Case "Open"
            OpenFile
        Case "Save"
            SaveFile
        Case "Cut"
            RichTextBox1.Cut
        Case "Copy"
            RichTextBox1.Copy
        Case "Paste"
            RichTextBox1.Paste
    End Select
End Sub

HTML 预览器

Private Sub LoadHTMLPreview(ByVal HTMLText As String)
    With RichTextBox1
        .TextMode = rtfHTML
        .Text = HTMLText
        .ReadOnly = True
    End With
End Sub

最佳实践

1. 文件操作

Private Sub SaveDocument(ByVal FilePath As String)
    On Error GoTo ErrorHandler
    
    With RichTextBox1
        If Right$(FilePath, 4) = ".rtf" Then
            .SaveFile FilePath, rtfRTF
        Else
            .SaveFile FilePath, rtfText
        End If
    End With
    Exit Sub
    
ErrorHandler:
    MsgBox "保存文件错误: " & Err.Description
End Sub

2. 撤销/重做管理

Private Sub ManageUndoRedo()
    ' 更新撤销/重做按钮状态
    cmdUndo.Enabled = RichTextBox1.CanUndo
    cmdRedo.Enabled = RichTextBox1.CanRedo
End Sub

3. 文本选择

Private Sub SelectWord()
    Dim StartPos As Long
    Dim EndPos As Long
    
    With RichTextBox1
        StartPos = .SelStart
        
        ' 查找单词边界
        While StartPos > 0 And Mid$(.Text, StartPos, 1) <> " "
            StartPos = StartPos - 1
        Wend
        
        EndPos = .SelStart
        While EndPos < Len(.Text) And Mid$(.Text, EndPos, 1) <> " "
            EndPos = EndPos + 1
        Wend
        
        .SelStart = StartPos
        .SelLength = EndPos - StartPos
    End With
End Sub

已知问题和解决方案

1. 内存使用

Private Sub OptimizeMemoryUsage()
    ' 处理大文本时分段加载
    Const CHUNK_SIZE As Long = 1000000 ' 1MB
    
    With RichTextBox1
        .Text = ""
        
        Open "largefile.txt" For Input As #1
        Do While Not EOF(1)
            .SelStart = .TextLength
            Line Input #1, TextLine
            .SelText = TextLine & vbCrLf
            DoEvents
        Loop
        Close #1
    End With
End Sub

2. 性能优化

Private Sub OptimizePerformance()
    ' 禁用重绘
    SendMessage RichTextBox1.hwnd, WM_SETREDRAW, 0, 0
    
    ' 执行批量操作
    ProcessLargeText
    
    ' 启用重绘
    SendMessage RichTextBox1.hwnd, WM_SETREDRAW, 1, 0
    RichTextBox1.Refresh
End Sub

其他提示

• 定期保存备份
• 实现自动换行
• 处理大文件
• 提供搜索功能
• 支持多种格式
• 实现打印功能
• 处理编码问题
• 提供状态信息
• 支持快捷键
• 在 Form_Unload 中清理资源

特殊用法

1. 创建语法高亮

Private Sub HighlightSyntax()
    Dim Keywords() As String
    Keywords = Split("Function,Sub,Dim,Private,Public,End", ",")
    
    With RichTextBox1
        Dim i As Long
        For i = 0 To UBound(Keywords)
            Dim pos As Long
            pos = 0
            Do
                pos = .Find(Keywords(i), pos)
                If pos = -1 Then Exit Do
                
                .SelStart = pos
                .SelLength = Len(Keywords(i))
                .SelColor = vbBlue
                .SelBold = True
                
                pos = pos + Len(Keywords(i))
            Loop
        Next i
    End With
End Sub

2. 创建自动完成

Private Sub SetupAutoComplete()
    Dim LastWord As String
    
    With RichTextBox1
        ' 获取当前单词
        Dim pos As Long
        pos = .SelStart - 1
        
        While pos >= 0 And Mid$(.Text, pos + 1, 1) <> " "
            LastWord = Mid$(.Text, pos + 1, 1) & LastWord
            pos = pos - 1
        Wend
        
        ' 显示建议列表
        If Len(LastWord) > 2 Then
            ShowSuggestions LastWord
        End If
    End With
End Sub

3. 创建邮件编辑器

Private Sub CreateMailEditor()
    With RichTextBox1
        ' 添加邮件头
        .SelText = "To: " & vbCrLf
        .SelText = "Subject: " & vbCrLf
        .SelText = String(50, "-") & vbCrLf & vbCrLf
        
        ' 设置签名
        .SelStart = .TextLength
        .SelText = vbCrLf & vbCrLf & "Best regards," & vbCrLf
        .SelText = "Your Name"
    End With
End Sub