Datagrid wpf c#应用程序中的复选框
我正在使用datagrid为学生记录创建一个C#wpf应用程序。 如何在标题中创建复选框以选中/取消选中行中的所有复选框? 如何单击选中行中的复选框,以便编辑/删除记录?以及我们如何选择多个要删除的复选框 使用这样的东西:Datagrid wpf c#应用程序中的复选框,c#,wpf,datagrid,C#,Wpf,Datagrid,我正在使用datagrid为学生记录创建一个C#wpf应用程序。 如何在标题中创建复选框以选中/取消选中行中的所有复选框? 如何单击选中行中的复选框,以便编辑/删除记录?以及我们如何选择多个要删除的复选框 使用这样的东西: DataGridCheckBoxColumn cbc = new DataGridCheckBoxColumn(); dataGrid.Columns.Add(cbc); CheckBox cb = new CheckBox(); cbc.Header = cb; <
DataGridCheckBoxColumn cbc = new DataGridCheckBoxColumn();
dataGrid.Columns.Add(cbc);
CheckBox cb = new CheckBox();
cbc.Header = cb;
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:WpfApplication2" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity" x:Class="WpfApplication2.MainWindow"
Title="MainWindow" mc:Ignorable="d" Height="350" Width="525">
<Window.Resources>
<Style x:Key="DataGridRowStyle" TargetType="{x:Type DataGridRow}">
<Setter Property="IsSelected" Value="{Binding IsSelected}"/>
</Style>
</Window.Resources>
<Window.DataContext>
<local:MainViewModel/>
</Window.DataContext>
<Grid>
<DataGrid AutoGenerateColumns="False" ItemsSource="{Binding Items}" CanUserAddRows="False" RowStyle="{DynamicResource DataGridRowStyle}">
<DataGrid.Columns>
<DataGridCheckBoxColumn Binding="{Binding IsSelected}">
<DataGridCheckBoxColumn.Header>
<CheckBox>
<i:Interaction.Behaviors>
<local:CollectionPropertyBehavior CollectionPropertyPath="IsSelected" SourcePropertyPath="IsChecked" ItemsSource="{Binding ItemsSource, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}"/>
</i:Interaction.Behaviors>
</CheckBox>
</DataGridCheckBoxColumn.Header>
</DataGridCheckBoxColumn>
<DataGridTextColumn Width="*" Binding="{Binding MyProperty}"/>
</DataGrid.Columns>
</DataGrid>
</Grid>
并处理选中的
和未选中的
事件:
cb.Checked+=new RoutedEventHandler(cb_Checked);
cb.Unchecked+=new RoutedEventHandler(cb_Unchecked);
我创建了一种行为,允许控件中的属性绑定到项集合的属性,其方式如下:
- 如果更改控件中的属性,则会更新所有项
- 如果更改项目中的属性,如果所有项目都具有相同的属性,则控件将反映该属性。如果不是,控件的属性将被赋予一个回退值(如null)
public class ItemViewModel : INotifyPropertyChanged
{
#region INotifyPropertyChanged
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string propertyName)
{
if (this.PropertyChanged != null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
#endregion
private bool isSelected;
public bool IsSelected {
get { return this.isSelected; }
set
{
if (this.isSelected == value)
return;
this.isSelected = value;
this.OnPropertyChanged("IsSelected");
}
}
private string myProperty;
public string MyProperty
{
get { return this.myProperty; }
set
{
if (this.myProperty != value)
{
this.myProperty = value;
this.OnPropertyChanged("MyProperty");
}
}
}
}
然后是MainViewModel,它控制主窗口的逻辑:
public class MainViewModel: INotifyPropertyChanged
{
#region INotifyPropertyChanged
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string propertyName)
{
if (this.PropertyChanged != null)
{
this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
#endregion
#region Items (INotifyPropertyChanged Property)
private ObservableCollection<ItemViewModel> items;
public ObservableCollection<ItemViewModel> Items
{
get { return this.items; }
set
{
if (this.items != value)
{
this.items = value;
this.OnPropertyChanged("Items");
}
}
}
#endregion
public MainViewModel()
{
this.Items = new ObservableCollection<ItemViewModel>();
for (int i = 0; i < 10; i++)
this.Items.Add(new ItemViewModel() { MyProperty = "Item" + i });
}
}
public类主视图模型:INotifyPropertyChanged
{
#区域inotifyproperty已更改
公共事件属性更改事件处理程序属性更改;
受保护的无效OnPropertyChanged(字符串propertyName)
{
if(this.PropertyChanged!=null)
{
this.PropertyChanged(this,newpropertychangedventargs(propertyName));
}
}
#端区
#区域项(INotifyPropertyChanged属性)
私人可观测收集项目;
公共可观测收集项目
{
获取{返回this.items;}
设置
{
if(this.items!=值)
{
这个项目=价值;
本协议项下的不动产变更(“项目”);
}
}
}
#端区
公共主视图模型()
{
this.Items=新的ObservableCollection();
对于(int i=0;i<10;i++)
this.Items.Add(新的ItemViewModel(){MyProperty=“Item”+i});
}
}
在我们的窗口中,我们可以声明DataGrid。为了实现您的愿望,我们必须做到以下几点:
- 将MainViewModel分配给Window.DataContext
- 将DataGrid.ItemsSource绑定到MainViewModel中的Items属性
- 定义DataGrid的列。在这个示例中,我选择了一个“IsSelected”列,并按照您的指定将“SelectAll”复选框添加到其标题中,但通过该行为,您可以在任何地方都有一个复选框来控制选择
- 我们需要对行的选择更新项目的“IsSelected”属性,反之亦然。为此,我们修改了RowStyle,以便可以将行的“IsSelected”属性绑定到其项的“IsSelected”。这样,选择逻辑现在可以完全由ViewModel驱动
- 最后一件事是让“SelectAll”复选框完成它的工作。我们应用CollectionPropertyBehavior并对其进行配置,使其“SourcePropertyPath”指向要绑定的复选框中的属性(“IsChecked”),CollectionPropertyPath指向项中的属性(“IsSelected”)。然后我们只需要将其ItemsSource绑定到DataGridItemsSource。请注意,默认值为“null”,这意味着当项目在其属性中具有不同的值时,复选框将接收“null”并处于未定义状态
DataGridCheckBoxColumn cbc = new DataGridCheckBoxColumn();
dataGrid.Columns.Add(cbc);
CheckBox cb = new CheckBox();
cbc.Header = cb;
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:WpfApplication2" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity" x:Class="WpfApplication2.MainWindow"
Title="MainWindow" mc:Ignorable="d" Height="350" Width="525">
<Window.Resources>
<Style x:Key="DataGridRowStyle" TargetType="{x:Type DataGridRow}">
<Setter Property="IsSelected" Value="{Binding IsSelected}"/>
</Style>
</Window.Resources>
<Window.DataContext>
<local:MainViewModel/>
</Window.DataContext>
<Grid>
<DataGrid AutoGenerateColumns="False" ItemsSource="{Binding Items}" CanUserAddRows="False" RowStyle="{DynamicResource DataGridRowStyle}">
<DataGrid.Columns>
<DataGridCheckBoxColumn Binding="{Binding IsSelected}">
<DataGridCheckBoxColumn.Header>
<CheckBox>
<i:Interaction.Behaviors>
<local:CollectionPropertyBehavior CollectionPropertyPath="IsSelected" SourcePropertyPath="IsChecked" ItemsSource="{Binding ItemsSource, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}"/>
</i:Interaction.Behaviors>
</CheckBox>
</DataGridCheckBoxColumn.Header>
</DataGridCheckBoxColumn>
<DataGridTextColumn Width="*" Binding="{Binding MyProperty}"/>
</DataGrid.Columns>
</DataGrid>
</Grid>
最后,行为:
public class CollectionPropertyBehavior : Behavior<DependencyObject>
{
private IEnumerable<ValueProxy> proxies;
private bool syncking;
public string SourcePropertyPath
{
get { return (string)GetValue(SourcePropertyPathProperty); }
set { SetValue(SourcePropertyPathProperty, value); }
}
public static readonly DependencyProperty SourcePropertyPathProperty =
DependencyProperty.Register("SourcePropertyPath", typeof(string), typeof(CollectionPropertyBehavior), new PropertyMetadata(null));
public string CollectionPropertyPath
{
get { return (string)GetValue(CollectionPropertyPathProperty); }
set { SetValue(CollectionPropertyPathProperty, value); }
}
public static readonly DependencyProperty CollectionPropertyPathProperty =
DependencyProperty.Register("CollectionPropertyPath", typeof(string), typeof(CollectionPropertyBehavior), new PropertyMetadata(null));
private IEnumerable<object> Items { get { return this.ItemsSource == null ? null : this.ItemsSource.OfType<object>(); } }
public IEnumerable ItemsSource
{
get { return (IEnumerable)GetValue(ItemsSourceProperty); }
set { SetValue(ItemsSourceProperty, value); }
}
public static readonly DependencyProperty ItemsSourceProperty =
DependencyProperty.Register("ItemsSource", typeof(IEnumerable), typeof(CollectionPropertyBehavior), new PropertyMetadata(null, ItemsSourceChanged));
private object Value
{
get { return (object)GetValue(ValueProperty); }
set { SetValue(ValueProperty, value); }
}
private static readonly DependencyProperty ValueProperty =
DependencyProperty.Register("Value", typeof(object), typeof(CollectionPropertyBehavior), new PropertyMetadata(null, ValueChanged));
public object DefaultValue
{
get { return (object)GetValue(DefaultValueProperty); }
set { SetValue(DefaultValueProperty, value); }
}
public static readonly DependencyProperty DefaultValueProperty =
DependencyProperty.Register("DefaultValue", typeof(object), typeof(CollectionPropertyBehavior), new PropertyMetadata(null));
private static void ValueChanged(object sender, DependencyPropertyChangedEventArgs args)
{
var element = sender as CollectionPropertyBehavior;
if (element == null || element.ItemsSource == null) return;
element.UpdateCollection();
}
private static void ItemsSourceChanged(object sender, DependencyPropertyChangedEventArgs args)
{
var element = sender as CollectionPropertyBehavior;
if (element == null || element.ItemsSource == null) return;
element.ItemsSourceChanged();
}
private void ItemsSourceChanged()
{
this.proxies = null;
if (this.Items == null || !this.Items.Any() || this.CollectionPropertyPath == null) return;
// Cria os proxies
this.proxies = this.Items.Select(o =>
{
var proxy = new ValueProxy();
proxy.Bind(o, this.CollectionPropertyPath);
proxy.ValueChanged += (s, e) => this.UpdateSource();
return proxy;
}).ToArray();
this.UpdateSource();
}
private void UpdateSource()
{
if (this.syncking) return;
// Atualiza o valor
using (new SynckingScope(this))
{
object value = this.proxies.First().Value;
foreach (var proxy in this.proxies.Skip(1))
{
value = object.Equals(proxy.Value, value) ? value : this.DefaultValue;
}
this.Value = value;
}
}
private void UpdateCollection()
{
// Se o valor estiver mudando em função da atualização de algum
// elemento da coleção, não faz nada
if (this.syncking) return;
using (new SynckingScope(this))
{
// Atualiza todos os elementos da coleção,
// atrávés dos proxies
if (this.proxies != null)
foreach (var proxy in this.proxies)
proxy.Value = this.Value;
}
}
protected override void OnAttached()
{
base.OnAttached();
// Bind da propriedade do objeto fonte para o behavior
var binding = new Binding(this.SourcePropertyPath);
binding.Source = this.AssociatedObject;
binding.Mode = BindingMode.TwoWay;
BindingOperations.SetBinding(this, ValueProperty, binding);
}
protected override void OnDetaching()
{
base.OnDetaching();
// Limpa o binding de value para a propriedade do objeto associado
this.ClearValue(ValueProperty);
}
internal class SynckingScope : IDisposable
{
private readonly CollectionPropertyBehavior parent;
public SynckingScope(CollectionPropertyBehavior parent)
{
this.parent = parent;
this.parent.syncking = true;
}
public void Dispose()
{
this.parent.syncking = false;
}
}
internal class ValueProxy : DependencyObject
{
public event EventHandler ValueChanged;
public object Value
{
get { return (object)GetValue(ValueProperty); }
set { SetValue(ValueProperty, value); }
}
public static readonly DependencyProperty ValueProperty =
DependencyProperty.Register("Value", typeof(object), typeof(ValueProxy), new PropertyMetadata(null, OnValueChanged));
private static void OnValueChanged(object sender, DependencyPropertyChangedEventArgs args)
{
var element = sender as ValueProxy;
if (element == null || element.ValueChanged == null) return;
element.ValueChanged(element, EventArgs.Empty);
}
public void Bind(object source, string path)
{
// Realiza o binding de value com o objeto desejado
var binding = new Binding(path);
binding.Source = source;
binding.Mode = BindingMode.TwoWay;
BindingOperations.SetBinding(this, ValueProperty, binding);
}
}
}
公共类CollectionPropertyBehavior:行为
{
私人可数代理;
私有布尔同步;
公共字符串SourcePropertyPath
{
get{return(string)GetValue(SourcePropertyPathProperty);}
set{SetValue(SourcePropertyPathProperty,value);}
}
公共静态只读DependencyProperty SourcePropertyPathProperty=
Register(“SourcePropertyPath”、typeof(string)、typeof(CollectionPropertyBehavior)、newPropertyMetadata(null));
公共字符串集合属性路径
{
get{return(string)GetValue(CollectionPropertyPathProperty);}
set{SetValue(CollectionPropertyPathProperty,value);}
}
公共静态只读DependencyProperty CollectionPropertyPathProperty=
Register(“CollectionPropertyPath”、typeof(string)、typeof(CollectionPropertyBehavior)、new PropertyMetadata(null));
私有IEnumerable项{get{返回this.ItemsSource==null?null:this.ItemsSource.OfType();}
公共IEnumerable ItemsSource
{
get{return(IEnumerable)GetValue(ItemsSourceProperty);}
set{SetValue(ItemsSourceProperty,value);}
}
公共静态只读依赖项Property ItemsSourceProperty=
DependencyProperty.Register(“ItemsSource”,typeof(IEnumerable),typeof(CollectionPropertyBehavior),new PropertyMetadata(null,ItemsSourceChanged));
私有对象值
{
获取{return(object)GetValue(ValueProperty);}
set{SetValue(ValueProperty,value);}
}
私有静态只读DependencyProperty ValueProperty=
Register(“Value”、typeof(object)、typeof(CollectionPropertyBehavior)、newpropertyMetadata(null、ValueChanged));
公共对象默认值
{
获取{return(object)GetValue(DefaultValueProperty);}
set{SetValue(DefaultValueProperty,value);}
}
公共静态只读从属属性DefaultValueProperty=
附属国