获取单词光标的方法是打开,在WPF RichTextBox控件中



我想知道如何在WPF RichTextBox中获取当前光标所在的单词。我知道RichTextBox具有选择属性。然而,这只给了我RichTextBox中突出显示的文本。相反,我想知道光标所在的单词,即使整个单词没有高亮显示。

任何提示都将不胜感激。

将此函数附加到任意RichTextBox(现在称为testRTB),并查看输出窗口以获取结果:

private void testRTB_MouseUp(object sender, MouseButtonEventArgs e)
{
        TextPointer start = testRTB.CaretPosition;  // this is the variable we will advance to the left until a non-letter character is found
        TextPointer end = testRTB.CaretPosition;    // this is the variable we will advance to the right until a non-letter character is found
        String stringBeforeCaret = start.GetTextInRun(LogicalDirection.Backward);   // extract the text in the current run from the caret to the left
        String stringAfterCaret = start.GetTextInRun(LogicalDirection.Forward);     // extract the text in the current run from the caret to the left
        Int32 countToMoveLeft = 0;  // we record how many positions we move to the left until a non-letter character is found
        Int32 countToMoveRight = 0; // we record how many positions we move to the right until a non-letter character is found
        for (Int32 i = stringBeforeCaret.Length - 1; i >= 0; --i)
        {
            // if the character at the location CaretPosition-LeftOffset is a letter, we move more to the left
            if (Char.IsLetter(stringBeforeCaret[i]))
                ++countToMoveLeft;
            else break; // otherwise we have found the beginning of the word
        }

        for (Int32 i = 0; i < stringAfterCaret.Length; ++i)
        {
            // if the character at the location CaretPosition+RightOffset is a letter, we move more to the right
            if (Char.IsLetter(stringAfterCaret[i]))
                ++countToMoveRight;
            else break; // otherwise we have found the end of the word
        }

        start = start.GetPositionAtOffset(-countToMoveLeft);    // modify the start pointer by the offset we have calculated
        end = end.GetPositionAtOffset(countToMoveRight);        // modify the end pointer by the offset we have calculated

        // extract the text between those two pointers
        TextRange r = new TextRange(start, end);
        String text = r.Text;

        // check the result
        System.Diagnostics.Debug.WriteLine("[" + text + "]");
}

根据您是否希望保留数字,将Char.IsLetter(…)更改为Char.IsLetterOrDigit(…)或其他适当的选项。

提示:将其提取到单独程序集中的扩展方法中,以便在需要时访问它。

好的,所以为了解决这个问题,我强行使用了它。

我曾经curCaret.GetTextInRun(LogicalDirection.Backward)curCaret.GetTextInRun(LogicalDirection.Forward)

以及CCD_ 6和CCD_

最后,我添加了字符串的前半部分和后半部分,以获得当前光标的单词

我打赌有更聪明的方法可以做到这一点,但至少这解决了问题

您可以通过CaretPosition获取光标的当前位置。

不幸的是,没有简单的方法可以将字符放在插入符号位置的左侧/右侧。我所知道的从RichTextBox中获取文本的唯一方法是这个答案,这有点复杂。但它将完成必要的任务。

由于单词是用空格分隔的,因此可以在插入符号周围循环,直到找到空格为止。即使RichTextBox包含不同的字体和字体大小,此功能也应该有效。

    public string GetWordByCaret(LogicalDirection direction)
    {
        // Get the CaretPosition
        TextPointer position = this.CaretPosition;
        TextPointerContext context = position.GetPointerContext(direction);
        string text = string.Empty;
        // Iterate through the RichTextBox based on the Start, Text and End of nearby inlines
        while (context != TextPointerContext.None)
        {
            // We are only interested in the text here
            //, so ignore everything that is not text
            if (context == TextPointerContext.Text)
            {
                string current = position.GetTextInRun(direction);
                // The strings appended based on whether they are before the caret or after it...
                // And well...I love switches :)
                switch (direction)
                {
                    case LogicalDirection.Backward:
                        {
                            int spaceIndex = current.LastIndexOf(' ');
                            // If space is found, we've reached the end
                            if (spaceIndex >= 0)
                            {
                                int length = current.Length - 1;
                                if (spaceIndex + 1 <= length)
                                {
                                    text = current.Substring(spaceIndex + 1, length - spaceIndex) + text;
                                }
                                return text;
                            }
                            else
                                text = current + text;
                        }
                        break;
                    default:
                        {
                            int spaceIndex = current.IndexOf(' ');
                            // If space is found, we've reached the end
                            if (spaceIndex >= 0)
                            {
                                int length = current.Length;
                                if (spaceIndex <= length)
                                {
                                    text += current.Substring(0, spaceIndex);
                                }
                                return text;
                            }
                            else
                                text += current;
                        }
                        break;
                }
            }
            // Move to the next position
            position = position.GetNextContextPosition(direction);
            // Get the next context
            if (position != null)
                context = position.GetPointerContext(direction);
            else
                context = TextPointerContext.None;
        }
        return text;
    }

现在你可以得到你插入的单词是这样的。

    string before = GetWordByCaret(LogicalDirection.Backward);
    string after = GetWordByCaret(LogicalDirection.Forward); 
    string word = before + after; // :)

以下是我使用LINQ和依赖属性的替代解决方案:

public class SelectionRichTextBox : RichTextBox
{
    public SelectionRichTextBox()
    {
        // Use base class style
        SetResourceReference(StyleProperty, typeof(RichTextBox));
    }
    public static readonly DependencyProperty SelectedWordProperty =
        DependencyProperty.Register(
                "SelectedWord",
                typeof(string),
                typeof(SelectionRichTextBox),
                new PropertyMetadata("")
                );
    public string SelectedWord
    {
        get
        {
            return (string)GetValue(SelectedWordProperty);
        }
        set
        {
            SetValue(SelectedWordProperty, value);
        }
    }
    protected override void OnMouseUp(MouseButtonEventArgs e)
    {
        TextPointer cursorPosition = CaretPosition;
        string strBeforeCursor = cursorPosition.GetTextInRun(LogicalDirection.Backward);
        string strAfterCursor = cursorPosition.GetTextInRun(LogicalDirection.Forward);
        string wordBeforeCursor = strBeforeCursor.Split().Last();
        string wordAfterCursor = strAfterCursor.Split().First();
        string text = wordBeforeCursor + wordAfterCursor;
        SelectedWord = string.Join("", text
            .Where(c => char.IsLetter(c))
            .ToArray());
        base.OnMouseUp(e);
    }
}

之后,您可以像这样在绑定中使用它:

    <custom:SelectionRichTextBox
            SelectedWord="{Binding SelectedWord, Mode=OneWayToSource}"/>

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