WPF.Basic.数据绑定

WPF常用五种数据绑定方式

  绑定方式一(绑定元素依赖属性)

<StackPanel>
    <Slider Name="s1" Value="10" Maximum="100"></Slider>
  
    <TextBlock FontSize="{Binding ElementName=s1,Path=Value}" Text="看着我" ></TextBlock>
</StackPanel>

  绑定方式二(绑定RelativeSources)

  第一种关系: Self

<TextBlock FontSize="18" FontWeight="Bold" Margin="10" 
Background="Red" Width="80" Height="{Binding RelativeSource={RelativeSource Self},Path=Width}">MultiBinding Sample</TextBlock>

第二种关系：TemplatedParent

<Style TargetType="{x:Type Button}"><Setter Property="Background" Value="Green"/><Setter Property="Template"><Setter.Value><ControlTemplate TargetType="{x:Type Button}"><Grid><Ellipse><Ellipse.Fill><SolidColorBrush Color="{Binding Path=Background.Color,RelativeSource={RelativeSource TemplatedParent}}"/>
</Style>

第三种关系：AncestorType

<Grid><Label Background = {Binding Path=Background, RelativeSource={RelativeSource FindAncestor   AncestorType={x:Type Grid}}}/>
</Grid>

绑定方式三(StaticResource静态资源/DynamicResource动态资源)

<Window.Resources>     
        <sys:String x:Key="Content" >
           Hello World!
        </sys:String>
    </Window.Resources>
    <Grid>
        <WrapPanel>
            <TextBlock Text="静态"/>
            <TextBox Text="{StaticResource Content}" Width="100" x:Name="TextBox1"/>
            <TextBlock Text="动态" Margin="10,0,0,0"/>
            <TextBox Text="{DynamicResource Content}" Width="100" x:Name="TextBox2"/>
            <Button Content="改变资源值" Click="ChangeBtn_Click" Width="100"/>       
        </WrapPanel>
    </Grid>

CS代码

private void ChangeBtn_Click(object sender, RoutedEventArgs e)
  {
      this.Resources["Content"] = "内容变了";
  } 

不管是动态资源还是静态资源,都需要现在资源里定义好"X:Name"资源扩展标记"资源字典"比如<sys:String x:Key="Content" > Hello World! </sys:String>

绑定方式四(绑定到集合元素 ItemSource)

 XAML代码

        <Border Grid.Row="2" Grid.Column="3">
            <ListBox
                x:Name="todoList"
                HorizontalContentAlignment="Stretch"
                ItemsSource="{Binding VarList}"
                ScrollViewer.VerticalScrollBarVisibility="Hidden">

                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <DockPanel MaxHeight="80" LastChildFill="False">
                            <ToggleButton DockPanel.Dock="Right" />
                            <StackPanel>
                                <TextBlock
                                    FontSize="16"
                                    FontWeight="Bold"
                                    Text="{Binding Name}" />
                                <TextBlock
                                    Margin="0,5"
                                    Opacity="0.5"
                                    Text="{Binding Value}" />
                                <TextBlock
                                    Margin="0,5"
                                    Opacity="0.5"
                                    Text="{Binding Description}" />
                                <TextBlock
                                    Margin="0,5"
                                    Opacity="0.5"
                                    Text="{Binding InsertTime}" />
                            </StackPanel>
                        </DockPanel>

                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>
        </Border>

  CS代码

        public ReportDataViewModel()
        {
            VarList.Add(new ActualData() { Description = "浮点数1", Name = "Float1", InsertTime = DateTime.Now, Value = CommonMethods.CurrentPLCValue["Float1"] });
            VarList.Add(new ActualData() { Description = "浮点数2", Name = "Float2", InsertTime = DateTime.Now, Value = CommonMethods.CurrentPLCValue["Float2"] });
            VarList.Add(new ActualData() { Description = "浮点数3", Name = "Float3", InsertTime = DateTime.Now, Value = CommonMethods.CurrentPLCValue["Float3"] });
            VarList.Add(new ActualData() { Description = "浮点数4", Name = "Float4", InsertTime = DateTime.Now, Value = CommonMethods.CurrentPLCValue["Float4"] });
        }


        private ObservableCollection<ActualData> varList = new ObservableCollection<ActualData>();

        public ObservableCollection<ActualData> VarList
        {
            get { return varList; }
            set { varList = value; }
        }

绑定方式五(DataContext)(最常规的绑定)

 XAML代码

 1 <Window x:Class="MyWPFSimple5.MainWindow"
 2         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 3         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 4         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
 5         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
 6         xmlns:local="clr-namespace:MyWPFSimple5"
 7         mc:Ignorable="d" DataContext="{Binding Source={StaticResource vmLocator}, Path=HelloObj}"
 8         Title="MainWindow" Height="250" Width="400">
 9     <Grid>
10         <StackPanel>
11             <TextBox Text="{Binding Say}" BorderBrush="Black" Margin="10"/>
12             <Button Content="改变内容" Click="Button_Click" Margin="10"/>
13         </StackPanel>
14     </Grid>
15 </Window>

  CS代码

 1 using System;
 2 using System.Collections.Generic;
 3 using System.ComponentModel;
 4 using System.Linq;
 5 using System.Text;
 6 using System.Threading.Tasks;
 7 using System.Windows;
 8 using System.Windows.Controls;
 9 using System.Windows.Data;
10 using System.Windows.Documents;
11 using System.Windows.Input;
12 using System.Windows.Media;
13 using System.Windows.Media.Imaging;
14 using System.Windows.Navigation;
15 using System.Windows.Shapes;
16 
17 namespace MyWPFSimple5
18 {
19     /// <summary>
20     /// MainWindow.xaml 的交互逻辑
21     /// </summary>
22     public partial class MainWindow : Window
23     {
24         public MainWindow()
25         {
26             InitializeComponent();
27         }
28 
29         private void Button_Click(object sender, RoutedEventArgs e)
30         {
31             Hello hello = DataContext as Hello;
32             hello.Say += "+1";
33         }
34     }
35 
36     public class Locator
37     {
38         public Locator()
39         {
40             //HelloObj = new Hello();
41         }
42 
43         private Hello m_HelloObj;
44         public Hello HelloObj
45         {
46             get
47             {
48                 if (m_HelloObj == null)
49                 {
50                     m_HelloObj = new Hello();
51                 }
52                 return m_HelloObj;
53             }
54             set
55             {
56                 m_HelloObj = value;
57             }
58         }
59     }
60 
61     public class Hello : INotifyPropertyChanged
62     {
63         public Hello()
64         {
65             Say = "Hello World!";
66         }
67         private string m_Say;
68         public string Say { get { return m_Say; } set { m_Say = value; RaisedPropertyChanged(nameof(Say)); } }
69 
70         public event PropertyChangedEventHandler PropertyChanged;
71         protected virtual void RaisedPropertyChanged(string name)
72         {
73             PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
74         }
75     }
76 }