我的visual studio写道,该<main>标签不受支持,但我使用的是HTML5验证器.此外,<nav>标签通过验证.问题是什么？http://i.gyazo.com/485e421e2f44202ee2905bb130719e01.png
<body>
<div id="main-wrapper">
<div style="width: auto; background-color: #00adae;">??????? ????</div>
<div id="gallery-wrapper">
<div id="categories-container">
<div id="categories-title">@Model.Name</div>
<div id="categories-menu-container">
@if (Model.Categories != null)
{
<nav id="categories-menu">
<ul>
@foreach (var category in Model.Categories)
{
<li>
<a href="#" data-category-id="@category.Id">@category.Name</a>
</li>
}
</ul>
</nav>
}
</div>
</div>
<div id="photos-masonry-container">
<div id="photos-masonry-title"></div>
<main id="photos-masonry"></main>
</div>
</div>
</div>
</body>
我需要写一个值转换器.像这样的东西:
public class HostStatusToDescriptionConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
return (bool)value == true ? "?????? ???????: ?????????" : "?????? ???????: ??????????";
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
return DependencyProperty.UnsetValue;
}
}
我需要在哪里使用MVVM模式？在模型文件夹中？或者创建一个转换器文件夹？
我需要禁用按钮一段时间才能运行.我有这个代码:
RelayCommand.cs这是我的命令类.
class RelayCommand : ICommand
{
readonly Action<object> _execute;
readonly Predicate<object> _canExecute;
public RelayCommand(Action<object> execute)
: this(execute, null)
{
}
public RelayCommand(Action<object> execute, Predicate<object> canExecute)
{
if (execute == null)
{
throw new ArgumentNullException("execute");
}
_execute = execute;
_canExecute = canExecute;
}
public bool CanExecute(object parameter)
{
return _canExecute == null ? true : _canExecute(parameter);
}
public event EventHandler CanExecuteChanged
{
add { CommandManager.RequerySuggested += value; }
remove { CommandManager.RequerySuggested -= value; }
}
public void Execute(object parameter) …我正在尝试 WPF 绑定。我写了一个小应用程序，但有问题，我的用户界面没有更新。这是我的代码：
<Grid>
<Button Content="Button" HorizontalAlignment="Left" Margin="345,258,0,0" VerticalAlignment="Top" Width="75" Click="Button_Click"/>
<TextBox x:Name="text" HorizontalAlignment="Left" Height="23" Margin="75,165,0,0" TextWrapping="Wrap" Text="{Binding Path=Count}" VerticalAlignment="Top" Width="311"/>
</Grid>
和代码隐藏：
namespace WpfApplication1
{
public partial class MainWindow : Window
{
MyClass mc;
public MainWindow()
{
InitializeComponent();
mc = new MyClass(this.Dispatcher);
text.DataContext = mc;
}
private void Button_Click(object sender, RoutedEventArgs e)
{
Task task = new Task(() =>
{
mc.StartCounting();
});
task.ContinueWith((previousTask) =>
{
},
TaskScheduler.FromCurrentSynchronizationContext());
task.Start();
}
}
public class MyClass
{
public int Count { get; …我正在创建一个学校成绩簿数据库.我有2张桌子:班级和老师.我有一个问题.老师需要成为班级的形式大师.我应该如何建立这种关系？
变体1: Class将具有teacherId属性.
变体2: 教师将拥有classId属性.
什么变体是对的？