第一次设置文本时，子类 RichTextBox OnTextChange 事件不会触发

Question

我已经将 RichTextBox 子类化以添加语法高亮显示，并且在手动更改文本时它工作正常。但是，当 Text 首次在代码中设置时，OnTextChanged 事件不会触发。

我的活动代码是

/// <summary>
/// When text changes keywords are searched for and highlighted
/// </summary>
/// <param name="e"></param>
protected override void OnTextChanged(EventArgs e)
{
    if (highlighting)
        return;

    int currentSelectionStart = this.SelectionStart;
    int currentSelectionLength = this.SelectionLength;

    base.OnTextChanged(e);

    String text = this.Text;
    this.Text = "";

    this.HighlightSyntax(text);

    this.SelectionStart = currentSelectionStart;
    this.SelectionLength = currentSelectionLength;
}

当从代码设置文本时，我如何才能触发此事件，例如this.structureInFileTextBox.Text = obj.FileStructure;？我已经尝试覆盖 Text 属性但这会使 Visual Studio 崩溃，我必须在再次打开项目之前从 .cs 文件中编辑它！

Answer 1

我会试试这个（我只在 base.Text = ""; 中更改了 this.Text = "";）：

/// <summary>
/// When text changes keywords are searched for and highlighted
/// </summary>
/// <param name="e"></param>
protected override void OnTextChanged(EventArgs e)
{
    if (highlighting)
        return;

    int currentSelectionStart = this.SelectionStart;
    int currentSelectionLength = this.SelectionLength;

    base.OnTextChanged(e);

    String text = this.Text;
    base.Text = "";

    this.HighlightSyntax(text);

    this.SelectionStart = currentSelectionStart;
    this.SelectionLength = currentSelectionLength;
}

并以这种方式覆盖文本属性：

public new string Text
{
    get { return base.Text; }
    set
    {
        if (base.Text != value)
        {
             base.Text = value;
             OnTextChanged(EventArgs.Empty);
        }
    }
}

第一次设置文本时，子类 RichTextBox OnTextChange 事件不会触发

Subclassed RichTextBox OnTextChange event doesn't fire when text first set

c#

richtextbox

winforms