如何在XAML中将颜色转换为画笔？ [英] How do I convert a Color to a Brush in XAML?

问题描述

我想将System.Windows.Media.Color值转换为System.Windows.Media.Brush。颜色值是数据绑定到一个Rectangle对象的Fill属性。 Fill属性需要一个Brush对象，所以我需要一个IValueConverter对象来执行转换。

有一个内置的转换器在WPF或者我需要创建我的拥有？

解决方案

看来你必须创建自己的转换器。下面是一个简单的例子：

  public class ColorToSolidColorBrushValueConverter：IValueConverter {
 
 public object Convert值，类型targetType，对象参数，System.Globalization.CultureInfo文化）{
 if（null == value）{
 return null; 
} 
 //对于一个更复杂的转换器，检查targetType并相应地做出反应。
 if（value is Color）{
 color color =（Color）value; 
 return new SolidColorBrush（color）; 
} 
 //如果你愿意，你可以在这里支持更多的源类型
 //例如我抛出一个异常
 
类型type = value.GetType（） ; 
 throw new InvalidOperationException（Unsupported type [+ type.Name +]）; 
} 
 
 public object ConvertBack（对象值，类型targetType，对象参数，System.Globalization.CultureInfo文化）{
 //如果需要，在这里你可以转换回来。检查它是否是刷（如果它的），
 //获得它的颜色值并返回它。 
 
 throw new NotImplementedException（）; 
} 
} 
  

要使用它，请在资源部分

 < local：ColorToSolidColorBrushValueConverter x：Key =ColorToSolidColorBrush_ValueConverter/> 
  

并且在绑定中使用它作为静态资源：

  Fill ={Binding Path = xyz，Converter = {StaticResource ColorToSolidColorBrush_ValueConverter}}
   
 
我没有测试它。如果它不工作，请发表评论。
 
I want to convert a System.Windows.Media.Color value to a System.Windows.Media.Brush. The color value is databound to a Rectangle object's Fill property. The Fill property takes a Brush object, so I need an IValueConverter object to perform the conversion.

Is there a built-in converter in WPF or do I need to create my own? How do I go about creating my own if it becomes necessary?
解决方案
It seems that you have to create your own converter. Here a simple example to start:
public class ColorToSolidColorBrushValueConverter : IValueConverter {

        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) {
            if (null == value) {
                return null;
            }
            // For a more sophisticated converter, check also the targetType and react accordingly..
            if (value is Color) {
                Color color = (Color)value;
                return new SolidColorBrush(color);
            }
            // You can support here more source types if you wish
            // For the example I throw an exception

            Type type = value.GetType();
            throw new InvalidOperationException("Unsupported type ["+type.Name+"]");            
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) {
            // If necessary, here you can convert back. Check if which brush it is (if its one),
            // get its Color-value and return it.

            throw new NotImplementedException();
        }
    }
To use it, declare it in the resource-section.
 <local:ColorToSolidColorBrushValueConverter  x:Key="ColorToSolidColorBrush_ValueConverter"/>
And the use it in the binding as a static resource:
  Fill="{Binding Path=xyz,Converter={StaticResource ColorToSolidColorBrush_ValueConverter}}"
I have not tested it. Make a comment if its not working.

                        
这篇关于如何在XAML中将颜色转换为画笔？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！