.net - .NET Framework：如何使 RichTextBox 成为真正的只读？

Question

将 RichTextBox 设置为“ReadOnly”不会阻止通过双击嵌入的对象（如方程式）来对其进行编辑。我可以禁用该控件，但随后会出现灰色背景（不能仅使用 BackColor 更改）并且无法滚动。我试图在派生类中覆盖 OnDoubleClick 但没有成功。

Answer 1

我找到了解决办法！:) 在派生类中：

protected override void WndProc(ref Message m)
    {
        if (m.Msg == 0x0203) // WM_LBUTTONDBLCLK
        {
            // Do nothing
        }
        else
        {
            base.WndProc(ref m);
        }
    }

Answer 2

我遇到了类似的问题，Entrase 的回答是一个好的开始。不幸的是，该控件仍然允许选择文本并将其删除。我最终使用了以下代码：

Public Class ReadOnlyRichTextBox : Inherits Windows.Forms.RichTextBox

    Protected mOkayKeys As Windows.Forms.Keys() = {Windows.Forms.Keys.Up, Windows.Forms.Keys.Down, Windows.Forms.Keys.PageUp, Windows.Forms.Keys.PageDown}

    Private Sub ReadOnlyRichTextBox_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyDown
        If e.Control And (e.KeyCode = Windows.Forms.Keys.C) Then
            Exit Sub
        End If
        If Not mOkayKeys.Contains(e.KeyCode) Then e.Handled = True
    End Sub

    Private Sub ReadOnlyRichTextBox_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles Me.KeyPress
        e.Handled = True
    End Sub

    Private Sub ReadOnlyRichTextBox_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyUp
        If e.Control And (e.KeyCode = Windows.Forms.Keys.C) Then
            Exit Sub
        End If
        If Not mOkayKeys.Contains(e.KeyCode) Then e.Handled = True
    End Sub

    Protected Overrides Sub WndProc(ByRef m As Windows.Forms.Message)
        If (m.Msg = &H203) Then ' WM_LBUTTONDBLCLK=0x0203
            ' Do nothing
        Else
            MyBase.WndProc(m)
        End If
    End Sub

End Class

Answer 3

嗯...只需尝试在双击时将 Sellength 设置为 0。没有只读/锁定属性吗？

Answer 4

这可以按如下方式完成

1) 将 RichTextBox 属性 ReadOnly 设置为 true

2）转到属性->外观->背景颜色并将颜色设置为窗口