public static Span ToSpan(this RichText richText, bool handleAccessKeyCharacter = true)
{
var span = new Span();
var length = -1;
var stack = ImmutableStack <Span> .Empty;
var currentUri = (Uri)null;
foreach (var part in richText.GetFormattedParts())
{
var substring = richText.Text.Substring(part.Offset, part.Length);
var inline = (Inline)null;
var linkData = richText.GetUserData <Uri>(part.Offset, part.Offset + part.Length);
if (currentUri != null && (linkData.Count == 0 || linkData[0] != currentUri))
{
var hyperlink = (Hyperlink)span;
span = stack.Peek();
stack = stack.Pop();
span.Inlines.Add(hyperlink);
currentUri = null;
}
if (linkData.Count != 0 && linkData[0] != currentUri)
{
currentUri = linkData[0];
stack = stack.Push(span);
span = new Hyperlink();
if (currentUri != RichTextConverter.EmptyLinkUri)
{
((Hyperlink)span).NavigateUri = currentUri;
}
GenericWeakEventManager.AddListener(
span,
"Click",
HyperlinkClickedWeakEventListener);
}
if (handleAccessKeyCharacter && substring.Length != 0)
{
length = length == -1 ? substring.IndexOf('_') : length;
if (length == substring.Length - 1)
{
length = 0;
}
else if (length == -1)
{
inline = new Run(substring);
}
else
{
var head = new Run(substring.Substring(0, length));
var mnemonic = new Run(substring.Substring(length + 1, 1));
var tail = new Run(substring.Substring(length + 2));
mnemonic.TextDecorations.Add(TextDecorations.Underline);
inline = new Span
{
Inlines =
{
head,
mnemonic,
tail
}
};
handleAccessKeyCharacter = false;
}
}
else
{
inline = new Run(substring);
}
if (inline == null)
{
continue;
}
span.Inlines.Add(inline);
// ReSharper disable RedundantCheckBeforeAssignment
if (part.Style.FontWeight != inline.FontWeight)
{
inline.FontWeight = part.Style.FontWeight;
}
if (part.Style.FontStyle != inline.FontStyle)
{
inline.FontStyle = part.Style.FontStyle;
}
if (part.Style.Foreground != null && part.Style.Foreground != inline.Foreground)
{
inline.Foreground = part.Style.Foreground;
}
if (part.Style.Background != null && part.Style.Background != inline.Background)
{
inline.Background = part.Style.Background;
}
// ReSharper restore RedundantCheckBeforeAssignment
var pen = (Pen)null;
if (part.Style.EffectBrush != null && part.Style.EffectBrush != part.Style.Foreground)
{
pen = new Pen {
Brush = part.Style.EffectBrush
}
}
;
switch (part.Style.Effect)
{
case TextEffectStyle.None:
continue;
case TextEffectStyle.StraightUnderline:
if (pen == null)
{
inline.TextDecorations = TextDecorations.Underline;
continue;
}
inline.TextDecorations.Add(
new TextDecoration
{
Location = TextDecorationLocation.Underline,
Pen = pen
});
continue;
case TextEffectStyle.WeavyUnderline:
if (pen == null)
{
inline.TextDecorations = TextDecorations.Underline;
continue;
}
inline.TextDecorations.Add(
new TextDecoration
{
Location = TextDecorationLocation.Underline,
Pen = pen
});
continue;
case TextEffectStyle.StrikeOut:
if (pen == null)
{
inline.TextDecorations = TextDecorations.Strikethrough;
continue;
}
inline.TextDecorations.Add(
new TextDecoration
{
Location = TextDecorationLocation.Strikethrough,
Pen = pen
});
continue;
default:
throw new InvalidOperationException("Invalid text effect: " + part.Style.Effect);
}
}
return(span);
}
}