How to databind public property in xaml
All I开发者_JS百科 am trying to do is bind a public property to a textBlock. What am I doing wrong here?
namespace WpfApplication1
{
public partial class MainWindow : Window
{
public string test { get; set; }
public MainWindow()
{
test = "this is a test";
InitializeComponent();
}
}
}
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<ObjectDataProvider x:Key="test"></ObjectDataProvider>
</Window.Resources>
<Grid>
<TextBlock Height="23" HorizontalAlignment="Left" Margin="108,58,0,0" Name="textBlock1" VerticalAlignment="Top" Text="{Binding Source={StaticResource test}}" />
</Grid>
You can simply add a datacontext and access your property
public partial class MainWindow : Window,INotifyPropertyChanged
{
private string _test;
public string test
{
get
{
return _test;
}
set
{
_test = value;
OnPropertyChanged("test");
}
}
public MainWindow()
{
test = "this is a test";
InitializeComponent();
DataContext = this;
}
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(String name)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(name));
}
}
}
<TextBlock Height="23" HorizontalAlignment="Left" Margin="108,58,0,0" Name="textBlock1" VerticalAlignment="Top" Text="{Binding test}"/>
Also check this post for details of when to use an ObjectDataProvider
http://bea.stollnitz.com/blog/?p=22
At first you need you class to implement INotifyPropertyChanged or a property to be DependencyProperty for changing property value on textbox text change,
namespace WpfApplication1
{
public partial class MainWindow : Window, INotifyPropertyChanged
{
private string _test
public string test
{
get
{
return _test;
}
set
{
_test = value;
OnPropertyChanged("test");
}
}
public MainWindow()
{
test = "this is a test";
InitializeComponent();
}
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(String info)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(info));
}
}
}
}
Than you can bind to that property by giving name to that window, and using ElementName property like this.
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525" Name="myWindow">
<Window.Resources>
<ObjectDataProvider x:Key="test"></ObjectDataProvider>
</Window.Resources>
<Grid>
<TextBlock Height="23" HorizontalAlignment="Left" Margin="108,58,0,0" Name="textBlock1" VerticalAlignment="Top" Text="{Binding ElementName=myWindow, Path=test}" />
</Grid>
You actually don't need to implement INotifyPropertyChanged. However, this will be a one time data binding.
For example in XAML:
<TextBlock Name="SomeTextBlock" Text="{Binding Path=SomeProp}" />
In Code:
public string SomeProp { get; set; }
public MainWindow()
{
InitializeComponent();
SomeProp = "Test Test Test";
SomeTextBlock.DataContext = this;
}
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