WPF RichTextBox语法突出显示问题
本文关键字：显示 问题 RichTextBox 语法 WPF | 更新日期: 2023-09-27 18:25:35
大家好，我一直在开发一个有文本编辑器的WPF应用程序，这个文本编辑器应该在一些标记（关键字）上应用一些样式或着色，以突出显示它并使其明显，问题是我非常努力地尝试了，但我仍然得到了相同的结果，即当用户输入其中一个关键字时，该关键字被样式化后的整个文本！想象一下，如果你在"C#"中键入"string"关键字，它后面的整个文本都会变成蓝色。
这是我使用的代码：
static List<string> tags = new List<string>(); static List<char> specials = new List<char>(); static string text; #region ctor static MainWindow() { string[] specialWords = { "string", "char", "null" }; tags = new List<string>(specialWords); // We also want to know all possible delimiters so adding this stuff. char[] chrs = { '.', ')', '(', '[', ']', '>', '<', ':', ';', ''n', ''t', ''r' }; specials = new List<char>(chrs); } public MainWindow() { InitializeComponent(); } #endregion //Now I should check statically if the string I passed is legal and constants in my dictionary public static bool IsKnownTag(string tag) { return tags.Exists(delegate(string s) { return s.ToLower().Equals(tag.ToLower()); }); } private static bool GetSpecials(char i) { foreach (var item in specials) { if (item.Equals(i)) { return true; } } return false; } // Wow. Great. Now I should separate words, that equals to my tags. For this propose we'll create new internal structure named Tag. This will help us to save words and its' positions. new struct Tag { public TextPointer StartPosition; public TextPointer EndPosition; public string Word; } internal void CheckWordsInRun(Run theRun){ //How, let's go through our text and save all tags we have to save. int sIndex = 0; int eIndex = 0; List<Tag> m_tags = new List<Tag>(); for (int i = 0; i < text.Length; i++) { if (Char.IsWhiteSpace(text[i]) | GetSpecials(text[i])) { if (i > 0 && !(Char.IsWhiteSpace(text[i - 1]) | GetSpecials(text[i - 1]))) { eIndex = i - 1; string word = text.Substring(sIndex, eIndex - sIndex + 1); if (IsKnownTag(word)) { Tag t = new Tag(); t.StartPosition = theRun.ContentStart.GetPositionAtOffset(sIndex, LogicalDirection.Forward); t.EndPosition = theRun.ContentStart.GetPositionAtOffset(eIndex + 1, LogicalDirection.Backward); t.Word = word; m_tags.Add(t); } } sIndex = i + 1; } } //How this works. But wait. If the word is last word in my text I'll never hightlight it, due I'm looking for separators. Let's add some fix for this case string lastWord = text.Substring(sIndex, text.Length - sIndex); if (IsKnownTag(lastWord)) { Tag t = new Tag(); t.StartPosition = theRun.ContentStart.GetPositionAtOffset(sIndex, LogicalDirection.Forward); t.EndPosition = theRun.ContentStart.GetPositionAtOffset(eIndex + 1, LogicalDirection.Backward); t.Word = lastWord; m_tags.Add(t); } //How I have all my words and its' positions in list. Let's color it! Dont forget to unsubscribe! text styling fires TextChanged event. txtStatus.TextChanged -= txtStatus_TextChanged; for (int i = 0; i < m_tags.Count; i++) { try { TextRange range = new TextRange(m_tags[i].StartPosition, m_tags[i].EndPosition); range.ApplyPropertyValue(TextElement.ForegroundProperty, new SolidColorBrush(Colors.Blue)); range.ApplyPropertyValue(TextElement.FontWeightProperty, FontWeights.Bold); } catch { } } m_tags.Clear(); txtStatus.TextChanged += txtStatus_TextChanged; }
这是文本更改事件处理程序
private void txtStatus_TextChanged(object sender, TextChangedEventArgs e) { if (txtStatus.Document == null) return; TextRange documentRange = new TextRange(txtStatus.Document.ContentStart, txtStatus.Document.ContentEnd); //documentRange.ClearAllProperties(); text = documentRange.Text; //Now let's create navigator to go though the text and hightlight it TextPointer navigator = txtStatus.Document.ContentStart; while (navigator.CompareTo(txtStatus.Document.ContentEnd) < 0) { TextPointerContext context = navigator.GetPointerContext(LogicalDirection.Backward); if (context == TextPointerContext.ElementStart && navigator.Parent is Run) { CheckWordsInRun((Run)navigator.Parent); } navigator = navigator.GetNextContextPosition(LogicalDirection.Forward); } }
任何建议或帮助都将不胜感激，提前表示感谢。
您应该高亮显示关键字，直到解析完所有文本，高亮显示每个Run中的关键字将影响对navigator.GetNextContextPosition的调用，从而导致意外错误，如重复触发textchanged事件。
在你高亮显示一个关键词后，你在该关键词后面键入的文本会继承该关键词的风格。一种解决方法是在高亮显示关键字之前对整个文本调用ClearAllProperties。
以下是更新后的txtStatus_TextChanged和CheckWordsInRun方法。
List<Tag> m_tags = new List<Tag>();
internal void CheckWordsInRun(Run theRun) //do not hightlight keywords in this method
{
//How, let's go through our text and save all tags we have to save.
int sIndex = 0;
int eIndex = 0;
for (int i = 0; i < text.Length; i++)
{
if (Char.IsWhiteSpace(text[i]) | GetSpecials(text[i]))
{
if (i > 0 && !(Char.IsWhiteSpace(text[i - 1]) | GetSpecials(text[i - 1])))
{
eIndex = i - 1;
string word = text.Substring(sIndex, eIndex - sIndex + 1);
if (IsKnownTag(word))
{
Tag t = new Tag();
t.StartPosition = theRun.ContentStart.GetPositionAtOffset(sIndex, LogicalDirection.Forward);
t.EndPosition = theRun.ContentStart.GetPositionAtOffset(eIndex + 1, LogicalDirection.Backward);
t.Word = word;
m_tags.Add(t);
}
}
sIndex = i + 1;
}
}
//How this works. But wait. If the word is last word in my text I'll never hightlight it, due I'm looking for separators. Let's add some fix for this case
string lastWord = text.Substring(sIndex, text.Length - sIndex);
if (IsKnownTag(lastWord))
{
Tag t = new Tag();
t.StartPosition = theRun.ContentStart.GetPositionAtOffset(sIndex, LogicalDirection.Forward);
t.EndPosition = theRun.ContentStart.GetPositionAtOffset(text.Length, LogicalDirection.Backward); //fix 1
t.Word = lastWord;
m_tags.Add(t);
}
}
private void txtStatus_TextChanged(object sender, TextChangedEventArgs e)
{
if (txtStatus.Document == null)
return;
txtStatus.TextChanged -= txtStatus_TextChanged;
m_tags.Clear();
//first clear all the formats
TextRange documentRange = new TextRange(txtStatus.Document.ContentStart, txtStatus.Document.ContentEnd);
documentRange.ClearAllProperties();
//text = documentRange.Text; //fix 2
//Now let's create navigator to go though the text, find all the keywords but do not hightlight
TextPointer navigator = txtStatus.Document.ContentStart;
while (navigator.CompareTo(txtStatus.Document.ContentEnd) < 0)
{
TextPointerContext context = navigator.GetPointerContext(LogicalDirection.Backward);
if (context == TextPointerContext.ElementStart && navigator.Parent is Run)
{
text = ((Run)navigator.Parent).Text; //fix 2
if (text != "")
CheckWordsInRun((Run)navigator.Parent);
}
navigator = navigator.GetNextContextPosition(LogicalDirection.Forward);
}
//only after all keywords are found, then we highlight them
for (int i = 0; i < m_tags.Count; i++)
{
try
{
TextRange range = new TextRange(m_tags[i].StartPosition, m_tags[i].EndPosition);
range.ApplyPropertyValue(TextElement.ForegroundProperty, new SolidColorBrush(Colors.Blue));
range.ApplyPropertyValue(TextElement.FontWeightProperty, FontWeights.Bold);
}
catch { }
}
txtStatus.TextChanged += txtStatus_TextChanged;
}