public static Paragraph Parse(string text, Style?style = null)
{
if (text is null)
{
throw new ArgumentNullException(nameof(text));
}
style ??= Style.Plain;
var result = new Paragraph();
using var tokenizer = new MarkupTokenizer(text);
var stack = new Stack <Style>();
while (tokenizer.MoveNext())
{
var token = tokenizer.Current;
if (token == null)
{
break;
}
if (token.Kind == MarkupTokenKind.Open)
{
var parsedStyle = StyleParser.Parse(token.Value);
stack.Push(parsedStyle);
}
else if (token.Kind == MarkupTokenKind.Close)
{
if (stack.Count == 0)
{
throw new InvalidOperationException($"Encountered closing tag when none was expected near position {token.Position}.");
}
stack.Pop();
}
else if (token.Kind == MarkupTokenKind.Text)
{
// Get the effective style.
var effectiveStyle = style.Combine(stack.Reverse());
result.Append(Emoji.Replace(token.Value), effectiveStyle);
}
else
{
throw new InvalidOperationException("Encountered unknown markup token.");
}
}
if (stack.Count > 0)
{
throw new InvalidOperationException("Unbalanced markup stack. Did you forget to close a tag?");
}
return(result);
}
/// <summary>
/// Removes markup from the specified string.
/// </summary>
/// <param name="text">The text to remove markup from.</param>
/// <returns>A string that does not have any markup.</returns>
public static string RemoveMarkup(this string?text)
{
if (string.IsNullOrWhiteSpace(text))
{
return(string.Empty);
}
var result = new StringBuilder();
var tokenizer = new MarkupTokenizer(text);
while (tokenizer.MoveNext() && tokenizer.Current != null)
{
if (tokenizer.Current.Kind == MarkupTokenKind.Text)
{
result.Append(tokenizer.Current.Value);
}
}
return(result.ToString());
}
/// <summary>
/// Parse the markup to RichTextParts and add them to the markuptextcontrol.
/// </summary>
/// <param name="markup"></param>
public void ParseMarkup(string markup)
{
MarkupTokenizer tokonizer = new MarkupTokenizer(markup);
tokonizer.FindTokens();
MarkupToken[] markuptokens = tokonizer.GetTokens();
SolidBrush solidbrushTextcolorDefault = new SolidBrush(Color.Black);
RichTextPart richtextpart = null;
bool previous_markuptokon_hyperlinktext = false;
for (int i = 0; i < markuptokens.Length; ++i)
{
if (markuptokens[i].IsLine)
{
richtextpart = new RichTextPart(Pens.Black);
this.markuptextcontrol.Append(richtextpart);
}
else
{
switch (markuptokens[i].CharLeft)
{
case '#':
// head
int headlevel = markuptokens[i].Level;
richtextpart = new RichTextPart(markuptokens[i].Text,
this.fontfamily,
this.headsfontsizes[headlevel],
solidbrushTextcolorDefault,
FontStyle.Bold);
richtextpart.AppendNewLine = true;
this.markuptextcontrol.Append(richtextpart);
previous_markuptokon_hyperlinktext = false;
break;
case '-':
// list
richtextpart = new RichTextPart(markuptokens[i].Text,
this.fontfamily,
this.fontsizedefault,
solidbrushTextcolorDefault,
FontStyle.Regular);
richtextpart.PrependBullit = true;
richtextpart.AppendNewLine = true;
this.markuptextcontrol.Append(richtextpart);
previous_markuptokon_hyperlinktext = false;
break;
case '*':
case '_':
// emphasis
int emphasislevel = markuptokens[i].Level;
int emphasisfontstyle = (int)FontStyle.Italic;
if (emphasislevel >= 1)
{
emphasisfontstyle = (int)FontStyle.Bold;
}
if (emphasislevel >= 2)
{
emphasisfontstyle += (int)FontStyle.Italic;
}
richtextpart = new RichTextPart(markuptokens[i].Text,
this.fontfamily,
this.fontsizedefault,
solidbrushTextcolorDefault,
(FontStyle)emphasisfontstyle);
this.markuptextcontrol.Append(richtextpart);
previous_markuptokon_hyperlinktext = false;
break;
case '~':
// strikethrough
richtextpart = new RichTextPart(markuptokens[i].Text,
this.fontfamily,
this.fontsizedefault,
solidbrushTextcolorDefault,
FontStyle.Strikeout);
this.markuptextcontrol.Append(richtextpart);
previous_markuptokon_hyperlinktext = false;
break;
case '[':
// hyperlink text
previous_markuptokon_hyperlinktext = true;
break;
case '(':
// hyperlink url
if (previous_markuptokon_hyperlinktext && i > 0)
{
FontStyle fontsylehyperlink = FontStyle.Underline;
SolidBrush solidbrushHyperlink = new SolidBrush(Color.Blue);
richtextpart = new RichTextPart(markuptokens[i - 1].Text,
this.fontfamily,
this.fontsizedefault,
solidbrushHyperlink,
fontsylehyperlink);
richtextpart.Href = markuptokens[i].Text;
this.markuptextcontrol.Append(richtextpart);
}
previous_markuptokon_hyperlinktext = false;
break;
case '`':
// TODO: literally and code highlighting
previous_markuptokon_hyperlinktext = false;
break;
default:
if (markuptokens[i].Nomarkup)
{
richtextpart = new RichTextPart(markuptokens[i].Text,
this.fontfamily,
this.fontsizedefault,
solidbrushTextcolorDefault,
FontStyle.Regular);
richtextpart.AppendNewLine = markuptokens[i].TextAppendNewLine;
this.markuptextcontrol.Append(richtextpart);
}
break;
}
}
}
this.markuptextcontrol.Refresh();
}
