Actual Date and Time bind to a Label

Wed, 20 Jun 2007 07:59:07 Z

Hello,

I'd like to bind the actual date and time to a Label. I tried the following code, but it doesn't work. Does anyone now why?

Code Snippet

<Window ...

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

xmlns:src="clr-namespace:System;assembly=mscorlib">

<Window.Resources>

</Window.Resources>

....

Why is it not working? Did I miss something or is my idea totally wrong?

Thanks

Chris

Actual Date and Time bind to a Label

Wed, 20 Jun 2007 08:15:48 Z

Hi Chris,

Now isn't a method, it's a property:

Code Snippet

<Window.Resources>

</Window.Resources>

But if you do it this way, the date is just initialized and never updated. Is this that what you want?

Actual Date and Time bind to a Label

Wed, 20 Jun 2007 08:30:55 Z

No,

i want that it will be updated all the time automatically. I thought I can do this with databinding. Isn't that right?

How should I do it instead?

Actual Date and Time bind to a Label

Wed, 20 Jun 2007 08:50:38 Z

Hi Chris,

the problem is that DateTime.Now has no mechanism for change-notification.

So you need a custom solution.

I would create an extra class that has only a now property and implements INotifyPropertyChanged. It could look like this:

Code Snippet

public class NotifyingDateTime:INotifyPropertyChanged

{

public event PropertyChangedEventHandler PropertyChanged;

private DateTime _now;

public NotifyingDateTime()

{

_now = DateTime.Now;

DispatcherTimer timer = new DispatcherTimer();

timer.Interval = TimeSpan.FromMilliseconds(100);

timer.Tick += new EventHandler(timer_Tick);

timer.Start();

}

public DateTime Now

{

get{return _now;}

private set

{

_now = value;

if(PropertyChanged!=null)

PropertyChanged(this,new PropertyChangedEventArgs("Now"));

}

void timer_Tick(object sender, EventArgs e)

{

Now = DateTime.Now;

}

In your XAML-File you could then just bind to the Now-Property of this class and will get always the current date and time.

If you need to show a different TimeFormat, you could use a ValueConverter to do that:

Code Snippet

<Window x:Class="MyApp.Window1"

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

xmlns:local="clr-namespace:MyApp"

Title="MyApp" Height="300" Width="300"

<Window.Resources>

<local:NotifyingDateTime x:Key="notifyingDate"/>

</Window.Resources>

</Window>

Thomas

Actual Date and Time bind to a Label

Wed, 20 Jun 2007 09:26:54 Z

Hello Thomas,

yeah it works fine. Thanks. I just needed to change something a bit. Just if someone wants to use it later as well:

Code Snippet

<Window.Resources>

</Window.Resources>

Thanks a lot.

Cheers

Chrsi