不断收到错误：标签不XML命名空间中(Keep getting error: The tag doe

我有一个测试Multibinding的项目。我想结合从TextBox2中的数据和textBox3到textBox1中。我试了一次又一次，但仍然得到了错误。

XAML：

<Window x:Class="Test_Multibiding.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="350" Width="621"
    xmlns:c="clr-namespace:Test_Multibiding">
<Window.Resources>
    <c:StringFormatConverter x:Key="StrConverter"/>
</Window.Resources>
<Grid>
    <TextBox TextWrapping="Wrap" AcceptsReturn="True" Height="269" HorizontalAlignment="Left" Margin="376,22,0,0" Name="textBox1" VerticalAlignment="Top" Width="211" >
        <TextBox.Text>
            <MultiBinding Converter="{StaticResource StrConverter}" StringFormat="test {0} test {1} blabla">
                <Binding ElementName="textBox2" Path="Text"/>
                <Binding ElementName="textBox3" Path="Text"/>
            </MultiBinding>
        </TextBox.Text>
    </TextBox>
    <TextBox Height="40" HorizontalAlignment="Left" Name="textBox2" VerticalAlignment="Top" Width="222"/>
    <TextBox Height="40" HorizontalAlignment="Left" Name="textBox3" VerticalAlignment="Top" Width="222"/>

</Grid>

主窗口

namespace Test_Multibiding
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        public class StringFormatConverter : IMultiValueConverter
        {
            public object Convert(object[] values, Type targetType,
               object parameter, System.Globalization.CultureInfo culture)
            {
                return string.Format(parameter.ToString(), values);
            }

            public object[] ConvertBack(object value, Type[] targetTypes,
               object parameter, System.Globalization.CultureInfo culture)
            {
                throw new NotSupportedException("Cannot convert back");
            }
        }
    }
}

而我得到的错误：

The tag 'StringFormatConverter' does not exist in XML namespace 'clr-namespace:Test_Multibiding'.

所以，请告诉我在哪里的问题呢？

Answer 1:

有事情的几个错在这里。首先，你不需要转换器。该StringFormat的财产MultiBinding会为你做到这一点。第二，如果你想使用自定义转换器，你需要设置ConverterParameter在MultiBinding ，不是StringFormat 。

现在，为什么你的转换器是不是该命名空间的原因：它宣告你的窗口类中。您转换器的全名是Test_Multibiding.MainWindow.StringFormatConverter 。它将编译（但你的Converter将有一个NullReferenceException的参数将是空），如果你改变你的类：

namespace Test_Multibiding
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
    }

    public class StringFormatConverter : IMultiValueConverter
    {
        public object Convert(object[] values, Type targetType,
           object parameter, System.Globalization.CultureInfo culture)
        {
            return string.Format(parameter.ToString(), values);
        }

        public object[] ConvertBack(object value, Type[] targetTypes,
           object parameter, System.Globalization.CultureInfo culture)
        {
            throw new NotSupportedException("Cannot convert back");
        }
    }
}

Answer 2:

你只需要移动StringFormatConverter出MainWindow类，像这样的：

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }
}

public class StringFormatConverter : IMultiValueConverter
{
    public object Convert(object[] values, Type targetType,
       object parameter, System.Globalization.CultureInfo culture)
    {
        return string.Format(parameter.ToString(), values);
    }

    public object[] ConvertBack(object value, Type[] targetTypes,
       object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotSupportedException("Cannot convert back");
    }
}