.net - 错误 - 在 WPF 应用程序中找不到静态资源

Question

我正在学习 WPF 并从 this 开始MSDN教程。

我只是按照教程。当我按照教程完成代码并尝试运行时，我在 XAML 页面中收到一个异常，上面写着

'Provide value on 'System.Windows.StaticResourceExtension' threw an exception.' Line number '27' and line position '55'." . And inner exception reveals that error is "Cannot find resource named 'personItemTemplate'. Resource names are case sensitive.".

罪魁祸首 XAML 如下。

<Page x:Class="ExpenseIt.ExpenseItHome"
      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
      xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
      xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
      mc:Ignorable="d" 
      d:DesignHeight="321" d:DesignWidth="532"
    Title="ExpenseIt - Home">

    <Grid Margin="10,0,10,10">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="230" />
            <ColumnDefinition />
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition />
            <RowDefinition Height="Auto" />
            <RowDefinition />
            <RowDefinition Height="Auto" />
        </Grid.RowDefinitions>
        <Label Grid.Column="1" Style="{StaticResource headerTextStyle}">View Expense Report</Label>
        <!-- Resource List Label-->
        <Border Grid.Column="1" Grid.Row="1" Style="{StaticResource listHeaderStyle}">
            <Label VerticalAlignment="Center" Foreground="White" FontWeight="Bold">Names</Label>
        </Border>
        <!-- Resource List-->
        <ListBox Name="peopleListBox" Grid.Column="1" Grid.Row="2" 
         ItemsSource="{Binding Source={StaticResource ExpenseDataSource}, XPath=Person}"
         ItemTemplate="{StaticResource personItemTemplate}">
        </ListBox>

        <!-- View button -->
        <Button Grid.Column="1" Grid.Row="3" Click="Button_Click" Style="{StaticResource buttonStyle}">View</Button>

        <!-- Set Background Image-->
        <Grid.Background>
            <ImageBrush ImageSource="watermark.png" />
        </Grid.Background>
        <Grid.Resources>

            <!-- Expense Report Data -->
            <XmlDataProvider x:Key="ExpenseDataSource" XPath="Expenses">
                <x:XData>
                    <Expenses xmlns="">
                        <Person Name="TommyVance" Department="Legal">
                            <Expense ExpenseType="Lunch" ExpenseAmount="50" />
                            <Expense ExpenseType="Transportation" ExpenseAmount="50" />
                        </Person>
                        <Person Name="PhilJackson" Department="Marketing">
                            <Expense ExpenseType="Document printing"
      ExpenseAmount="50"/>
                            <Expense ExpenseType="Gift" ExpenseAmount="125" />
                        </Person>
                        <Person Name="PaulBriggs" Department="Engineering">
                            <Expense ExpenseType="Magazine subscription" 
     ExpenseAmount="50"/>
                            <Expense ExpenseType="New machine" ExpenseAmount="600" />
                            <Expense ExpenseType="Software" ExpenseAmount="500" />
                        </Person>
                        <Person Name="AlfredNobel" Department="Finance">
                            <Expense ExpenseType="Dinner" ExpenseAmount="100" />
                        </Person>
                    </Expenses>
                </x:XData>
            </XmlDataProvider>
            <!-- Data Template to mention that Name should be fetched from the XMLDataProvider -->
            <!-- Name item template -->
            <DataTemplate x:Key="personItemTemplate">
                <Label Content="{Binding XPath=@Name}"/>
            </DataTemplate>
        </Grid.Resources>
    </Grid>
</Page>

我在 Grid 资源中有所需的模板，因此将其添加为静态资源。尽管如此，它仍会引发数据模板不可用的异常。

Answer 1

移动 <Grid.Resources> ... </Grid.Resources>到您的网格定义的顶部，它将起作用。 DataTemplate 似乎需要在引用之前定义。我将您的示例复制到一个应用程序中，并确认将资源部分向上移动解决了问题。