windows-phone-7 – 错误：System.Windows.ni.dll中出现’System.Windows.Markup.XamlParseException’类型的第一次机会异常

A first chance exception of type 'System.Windows.Markup.XamlParseException' occurred in System.Windows.ni.dll

错误发生在intializecomponent()中的app.xaml文件中;方法

public App()
    {
        // Global handler for uncaught exceptions.
        UnhandledException += Application_UnhandledException;

        // Standard XAML initialization
        InitializeComponent();

        // Phone-specific initialization
        InitializePhoneApplication();

由于我在添加应用程序资源时发生错误

<converter:RSSTextTrimmer xmlns:converter="clr-namespace:HomePage" x:Key="RSSTextTrimmer" />

当我删除它时,应用程序运行良好.

以下是完整代码：

<Application
x:Class="HomePage.App"
xmlns="http://scheR_195_11845@as.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://scheR_195_11845@as.microsoft.com/winfx/2006/xaml"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:sHell="clr-namespace:Microsoft.Phone.SHell;assembly=Microsoft.Phone">

<!--Application resources-->
<Application.resources>
    <local:LocalizedStrings xmlns:local="clr-namespace:HomePage" x:Key="LocalizedStrings"/>
    <converter:RSSTextTrimmer xmlns:converter="clr-namespace:HomePage" x:Key="RSSTextTrimmer" />

</Application.resources>

<Application.ApplicationLifetimeObjects>
    <!--required object that handles lifetime events for the application-->
    <sHell:PhoneApplicationservice
        Launching="Application_Launching" Closing="Application_Closing"
        Activated="Application_Activated" Deactivated="Application_Deactivated"/>
</Application.ApplicationLifetimeObjects>

转换器代码

命名空间HomePage
{
    class RSSTextTrimmer：IValueConverter
    {

// Clean up text fields from each SynDicationItem. 
    public object Convert(object value,Type targetType,object parameter,CultureInfo culturE)
    {
        if (value == null) return null;

        int maxLength = 200;
        int strLength = 0;
        String fixedString = "";

        // Remove HTML tags and newline characters from the text,and decodes HTML encoded characters. 
        // This is a basic method. Additional code would be needed to more thoroughly  
        // remove certain elements,such as embedded Javascript. 

        // Remove HTML tags. 
        fixedString = Regex.replace(value.ToString(),"<[^>]+>",String.Empty);

        // Remove newline characters
        fixedString = fixedString.replace("\r","").replace("\n","");

        // Remove encoded HTML characters
        fixedString = httpUtility.HtmlDecode(fixedString);

        strLength = fixedString.ToString().Length;



        // Some Feed management tools include an image tag in the Description field of an RSS Feed,// so even if the Description field (and thus,the SumMary property) is not populated,it Could still contain HTMl. 
        // Due to this,after we Strip tags from the String,we should return null if there is nothing left in the resulTing String. 
        if (strLength == 0)
        {
            return null;
        }

        // Truncate the text if it is too long. 
        else if (strLength >= maxLength)
        {
            fixedString = fixedString.SubString(0,maxLength);

            // Unless we take the next step,the String truncation Could occur in the middle of a word.
            // Using LasTindexOf we can find the last space character in the String and truncate there. 
            fixedString = fixedString.SubString(0,fixedString.LasTindexOf(" "));
        }

        fixedString += "...";

        return fixedString;
    }

    // This code sample does not use TwoWay binding and thus,we do not need to flesh out ConvertBACk.  
    public object ConvertBACk(object value,CultureInfo culturE)
    {
        throw new NotImplementedException();
    }
}

}