XAML将文本块文本转换为内联
本文关键字:文本 XAML 转换 | 更新日期: 2023-09-27 18:25:51
我想在UWP项目的TextBlock上设置这种文本:
"<Bold>" + variable + "</Bold>"
但将其设置为Text值时不考虑<Bold>
标记。
所以我搜索了如何做,唯一的答案是"创建Inlines并将其添加到您的textBlock"。但我不想在我的视图模型上这样做。
因此,我正在寻找一个转换器,用在我的textBlock上设置的内联集合来替换我的文本属性。我找到了一些例子(https://social.msdn.microsoft.com/Forums/en-US/1a1af975-e186-4167-b1c9-cc86afcdd93a/how-to-show-text-in-textblock-as-rich-text-format?forum=wpf),但不适用于通用Windows应用程序(UWP)。
我试过了,但我有一个错误(无法将绑定转换为字符串):
<TextBlock x:Name="newsArticleSections"
Tag="{Binding RelativeSource={RelativeSource Self}, Mode=OneWay, Converter={StaticResource TextToRunConverter}, ConverterParameter={Binding ArticleSections}}"/>
这是我的转换器:
public object Convert(object value, Type targetType, object parameter, string language)
{
TextBlock textblock = value as TextBlock;
textblock.ClearValue(TextBlock.TextProperty);
Run run = new Run();
run.Text = (string)parameter;
textblock.Inlines.Add(run);
return null;
}
这只是我探索过的方法,但暂时没有结果。有人有其他想法吗?
@devuxer的回答是个好主意,但仅适用于WPF项目。所以我用它来制作UWP解决方案,它很有效:
创建格式化程序类:
public class TextBlockFormatter
{
public static readonly DependencyProperty FormattedTextProperty = DependencyProperty.RegisterAttached(
"FormattedText",
typeof(string),
typeof(TextBlockFormatter),
new PropertyMetadata(null, FormattedTextPropertyChanged));
public static void SetFormattedText(DependencyObject textBlock, string value)
{
textBlock.SetValue(FormattedTextProperty, value);
}
public static string GetFormattedText(DependencyObject textBlock)
{
return (string)textBlock.GetValue(FormattedTextProperty);
}
private static void FormattedTextPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
// Clear current textBlock
TextBlock textBlock = d as TextBlock;
textBlock.ClearValue(TextBlock.TextProperty);
textBlock.Inlines.Clear();
// Create new formatted text
string formattedText = (string)e.NewValue ?? string.Empty;
string @namespace = "http://schemas.microsoft.com/winfx/2006/xaml/presentation";
formattedText = $@"<Span xml:space=""preserve"" xmlns=""{@namespace}"">{formattedText}</Span>";
// Inject to inlines
var result = (Span)XamlReader.Load(formattedText);
textBlock.Inlines.Add(result);
}
}
并将此引用添加到XAML文件:
xmlns:helpers="using:MyProject.Helpers"
要使用格式化程序,只需添加一个TextBlock并声明您对FormattedText的绑定,如下所示:
<TextBlock x:Name="textBlock" helpers:TextBlockFormatter.FormattedText="{Binding Content}">
我一直在为WPF项目(而不是UWP)使用以下解决方案,所以我不确定它是否适用于您,但可以尝试一下。
您首先将以下内容放入项目中Helpers文件夹中的类文件中:
public class Formatter
{
public static readonly DependencyProperty FormattedTextProperty = DependencyProperty.RegisterAttached(
"FormattedText",
typeof(string),
typeof(Formatter),
new FrameworkPropertyMetadata(string.Empty, FrameworkPropertyMetadataOptions.AffectsMeasure, FormattedTextPropertyChanged));
public static void SetFormattedText(DependencyObject textBlock, string value)
{
textBlock.SetValue(FormattedTextProperty, value);
}
public static string GetFormattedText(DependencyObject textBlock)
{
return (string)textBlock.GetValue(FormattedTextProperty);
}
private static void FormattedTextPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var textBlock = d as TextBlock;
if (textBlock == null) return;
const string @namespace = "http://schemas.microsoft.com/winfx/2006/xaml/presentation";
var formattedText = (string)e.NewValue ?? string.Empty;
formattedText = $@"<Span xml:space=""preserve"" xmlns=""{@namespace}"">{formattedText}</Span>";
textBlock.Inlines.Clear();
using (var xmlReader = XmlReader.Create(new StringReader(formattedText)))
{
var result = (Span)XamlReader.Load(xmlReader);
textBlock.Inlines.Add(result);
}
}
}
然后,在XAML文件中,引用命名空间,如下所示:
xmlns:helpers="clr-namespace:MyProject.Helpers"
要使用格式化程序,只需添加一个TextBlock
并在FormattedText
(而不是Text
)上声明绑定,如下所示:
<TextBlock helpers:Formatter.FormattedText="{Binding Content}" />
我使用这样的东西:
XAML
<TextBlock Name="TB" Text="Bold Text " FontWeight="Bold" />
在控制器处:
TB.Inlines.Add(new Run { Text = "New append text with diferent FontWeigth on the same TextBlock", FontWeight = FontWeights.Normal } );
输出为:
粗体文本在同一个TextBlock 上使用不同字体大小的新追加文本
我希望我的贡献仍然有用,或者可能对其他人提出这个问题有用。我已经从@Geoffrey更新了Formatter类,因此textblock
中的特定字符是turning粗体。我有一个人员列表,顶部有一个搜索查询。人员名称中的查询部分正在变为粗体。
查询:ic
结果:Rick
public class TextBlockFormatter
{
const string @namespace = "http://schemas.microsoft.com/winfx/2006/xaml/presentation";
public static readonly DependencyProperty FormattedTextProperty = DependencyProperty.RegisterAttached(
"FormattedText",
typeof(string),
typeof(TextBlockFormatter),
new PropertyMetadata(null, FormattedTextPropertyChanged));
public static void SetFormattedText(DependencyObject textBlock, string value)
{
textBlock.SetValue(FormattedTextProperty, value);
}
public static string GetFormattedText(DependencyObject textBlock)
{
return (string)textBlock.GetValue(FormattedTextProperty);
}
private static void FormattedTextPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var textBlock = (TextBlock)d;
if (textBlock.DataContext == null)
{
textBlock.DataContextChanged += TextBlock_DataContextChanged;
return;
}
var query = (string)e.NewValue ?? string.Empty;
HighlightSearch(textBlock, query);
}
private static void HighlightSearch(TextBlock textBlock, string value)
{
var name = ((Person)textBlock.DataContext).Name;
var query = value.ToUpper();
var indexOfSearch = name.ToUpper().IndexOf(query, 0);
if (indexOfSearch < 0) return;
// add normal text first
var firstText = name.Substring(0, indexOfSearch).Replace("&", "&");
var first = $@"<Span xml:space=""preserve"" xmlns=""{@namespace}"">{firstText}</Span>";
var firstResult = (Span)XamlReader.Load(first);
// add the bold text
var boldText = name.Substring(indexOfSearch, query.Length).Replace("&", "&");
var bold = $@"<Bold xml:space=""preserve"" xmlns=""{@namespace}"">{boldText}</Bold>";
var boldResult = (Bold)XamlReader.Load(bold);
// add the rest of the text
var restStartIndex = indexOfSearch + query.Length;
var restText = name.Substring(restStartIndex, name.Length - restStartIndex).Replace("&", "&");
var rest = $@"<Span xml:space=""preserve"" xmlns=""{@namespace}"">{restText}</Span>";
var restResult = (Span)XamlReader.Load(rest);
// Clear current textBlock
textBlock.ClearValue(TextBlock.TextProperty);
textBlock.Inlines.Clear();
// Inject to inlines
textBlock.Inlines.Add(firstResult);
textBlock.Inlines.Add(boldResult);
textBlock.Inlines.Add(restResult);
}
private static void TextBlock_DataContextChanged(FrameworkElement sender, DataContextChangedEventArgs args)
{
var block = (TextBlock)sender;
if (block.DataContext == null) return;
block.DataContextChanged -= TextBlock_DataContextChanged;
var query = (string)sender.GetValue(FormattedTextProperty);
HighlightSearch(block, query);
}
}
在XAML中使用:
<TextBlock Text="{Binding Name}" helpers:TextBlockFormatter.FormattedText="{Binding ElementName=queryTextBox, Path=Text}" />
我遇到了一些问题,例如,当调用FormattedTextPropertyChanged
时,我的datasource
没有设置。此外,您还需要注意转义文本。我通过使用Replace
函数使自己变得轻松。