C# WPF error: System.Windows.Markup.XamlParseException: ''Failed to create a 'RequestNavigate' from the text 'Hyperlink_RequestNavigate'.'

Question

我需要创建一个 WPF 应用程序，在其中显示从网站上抓取的文本。在每个新的一天，文本都会更改。然而，问题是这个文本包含超链接，我也需要抓取它们。从这个意义上说，我正在抓取 innerHtml 并修改为 XAML.

可读

假设我正在抓取这个 HTML:

<p>Click <a href="google.com"> here </a> !!</p>

我将其修改为 XAML 可读，如下所示：

<TextBlock> Click <Hyperlink RequestNavigate=\"Hyperlink_RequestNavigate\" NavigateUri='https://www.google.com/'> here </Hyperlink> !!! </TextBlock>

我该怎么做？

public partial class MainWindow : Window
{    
    public MainWindow()
    {
        InitializeComponent();
        var str = " Click <Hyperlink RequestNavigate=\"Hyperlink_RequestNavigate\" NavigateUri='https://www.google.com/'> here </Hyperlink> !!! ";
        grid.Children.Add(CreateTextBlock(str));
    }

    public TextBlock CreateTextBlock(string inlines)
    {
        var xaml = "<TextBlock xmlns=\"http://schemas.microsoft.com/winfx/2006/xaml/presentation\">"
            + inlines + "</TextBlock>";
        return XamlReader.Parse(xaml) as TextBlock;
    }

    public void Hyperlink_RequestNavigate(object sender, RequestNavigateEventArgs e)
    {
        Process.Start(new ProcessStartInfo(e.Uri.AbsoluteUri) { UseShellExecute = true });
        e.Handled = true;
    }
}

到现在为止都很好，但是上面的错误出现了：

System.Windows.Markup.XamlParseException: ''Failed to create a 'RequestNavigate' from the text 'Hyperlink_RequestNavigate'.' ArgumentException: Cannot bind to the target method because its signature is not compatible with that of the delegate type.

感谢您的帮助。

Answer 1

XamlReader.Parse 方法不支持事件处理程序，但您可以简单地从正在解析的 XAML 中删除 RequestNavigate="Hyperlink_RequestNavigate" 并处理所有超链接的 RequestNavigate 事件将路由事件的事件处理程序附加到 Grid:

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
        var str = " Click <Hyperlink NavigateUri='https://www.google.com/'> here </Hyperlink> !!! ";
        grid.Children.Add(CreateTextBlock(str));
        grid.AddHandler(Hyperlink.RequestNavigateEvent, new RequestNavigateEventHandler(Hyperlink_RequestNavigate));
    }

    public TextBlock CreateTextBlock(string inlines)
    {
        var xaml = "<TextBlock xmlns=\"http://schemas.microsoft.com/winfx/2006/xaml/presentation\">"
            + inlines + "</TextBlock>";
        return XamlReader.Parse(xaml) as TextBlock;
    }

    public void Hyperlink_RequestNavigate(object sender, RequestNavigateEventArgs e)
    {
        Process.Start(new ProcessStartInfo(e.Uri.AbsoluteUri) { UseShellExecute = true });
        e.Handled = true;
    }
}

C# WPF error: System.Windows.Markup.XamlParseException: ''Failed to create a 'RequestNavigate' from the text 'Hyperlink_RequestNavigate'.'

C# WPF error: System.Windows.Markup.XamlParseException: ''Failed to create a 'RequestNavigate' from the text 'Hyperlink_RequestNavigate'.'

c#

html

wpf

hyperlink

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