Add hyperlink to textblock wpf

问题:

Greetings, I have some text in a db and it is as follows:

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Duis tellus nisl, venenatis et pharetra ac, tempor sed sapien. Integer pellentesque blandit velit, in tempus urna semper sit amet. Duis mollis, libero ut consectetur interdum, massa tellus posuere nisi, eu aliquet elit lacus nec erat. Praesent a commodo quam. **[a href='http://somesite.com']some site[/a]**Suspendisse at nisi sit amet massa molestie gravida feugiat ac sem. Phasellus ac mauris ipsum, vel auctor odio

My question is: How can I display a Hyperlink in a TextBlock? I don't want to use a webBrowser control for this purpose. I don't want to use this control either: http://www.codeproject.com/KB/WPF/htmltextblock.aspx also

回答1:

You can use Regex with a value converter in such situation.

Use this for your requirements (original idea from here):

    private Regex regex = 
        new Regex(@"\[a\s+href='(?<link>[^']+)'\](?<text>.*?)\[/a\]",
        RegexOptions.Compiled);

This will match all links in your string containing links, and make 2 named groups for each match : link and text

Now you can iterate through all the matches. Each match will give you a

    foreach (Match match in regex.Matches(stringContainingLinks))
    { 
        string link    = match.Groups["link"].Value;
        int link_start = match.Groups["link"].Index;
        int link_end   = match.Groups["link"].Index + link.Length;

        string text    = match.Groups["text"].Value;
        int text_start = match.Groups["text"].Index;
        int text_end   = match.Groups["text"].Index + text.Length;

        // do whatever you want with stringContainingLinks.
        // In particular, remove whole `match` ie [a href='...']...[/a]
        // and instead put HyperLink with `NavigateUri = link` and
        // `Inlines.Add(text)` 
        // See the answer by Stanislav Kniazev for how to do this
    }

Note : use this logic in your custom ConvertToHyperlinkedText value converter.

回答2:

Displaying is rather simple, the navigation is another question. XAML goes like this:

<TextBlock Name="TextBlockWithHyperlink">
    Some text 
    <Hyperlink 
        NavigateUri="http://somesite.com"
        RequestNavigate="Hyperlink_RequestNavigate">
        some site
    </Hyperlink>
    some more text
</TextBlock>

And the event handler that launches default browser to navigate to your hyperlink would be:

private void Hyperlink_RequestNavigate(object sender, RequestNavigateEventArgs e) {
    System.Diagnostics.Process.Start(e.Uri.ToString());
}

Edit: To do it with the text you've got from database you'll have to parse the text somehow. Once you know the textual parts and hyperlinked parts, you can build textblock contents dynamically in the code:

TextBlockWithHyperlink.Inlines.Clear();
TextBlockWithHyperlink.Inlines.Add("Some text ");
Hyperlink hyperLink = new Hyperlink() {
    NavigateUri = new Uri("http://somesite.com")
};
hyperLink.Inlines.Add("some site");
hyperLink.RequestNavigate += Hyperlink_RequestNavigate;
TextBlockWithHyperlink.Inlines.Add(hyperLink);
TextBlockWithHyperlink.Inlines.Add(" Some more text");