Canvas.Left Attached Property
Gets or sets a value that represents the distance between the left side of an element and the left side of its parent Canvas.

Namespace: System.Windows.Controls
Assembly: PresentationFramework (in PresentationFramework.dll)
XML Namespace:  http://schemas.microsoft.com/winfx/2006/xaml/presentation

Syntax
Visual Basic (Declaration) 
See Canvas.GetLeft, Canvas.SetLeft
Visual Basic (Usage) 
See Canvas.GetLeft, Canvas.SetLeft
C# 
See Canvas.GetLeft, Canvas.SetLeft
C++ 
See Canvas.GetLeft, Canvas.SetLeft
J# 
See Canvas.GetLeft, Canvas.SetLeft
JScript 
See Canvas.GetLeft, Canvas.SetLeft
XAML Attribute Usage 
<object Canvas.Left="double" .../>

Property Value

A Double that represents the offset position from the left side of a parent Canvas. The default value is NaN.
Dependency Property Information

Identifier field

LeftProperty

Metadata properties set to true

None
Remarks

The Left offset of a child element does not affect the size of a parent Canvas.

If you specify them, the attached properties Top or Left take priority over Bottom or Right properties.
Example

This example shows how to use the attached properties of Canvas to position child elements.

The following example adds four Button elements as child elements of a parent Canvas. Each child element represents a distinct attached property of Canvas: Bottom, Left, Right, and Top. Each Button is positioned relative to the parent Canvas and according to its assigned property value.

C++ 
// Create the application's main window
mainWindow = gcnew System::Windows::Window();
mainWindow->Title = "Canvas Attached Properties Sample";

// Add a Border
Border^ myBorder = gcnew Border();
myBorder->HorizontalAlignment = HorizontalAlignment::Left;
myBorder->VerticalAlignment = VerticalAlignment::Top;
myBorder->BorderBrush = Brushes::Black;
myBorder->BorderThickness = System::Windows::Thickness(2);

// Create the Canvas
Canvas^ myCanvas = gcnew Canvas();
myCanvas->Background = Brushes::LightBlue;
myCanvas->Width = 400;
myCanvas->Height = 400;

// Create the child Button elements
Button^ myButton1 = gcnew Button();
Button^ myButton2 = gcnew Button();
Button^ myButton3 = gcnew Button();
Button^ myButton4 = gcnew Button();

// Set Positioning attached properties on Button elements
Canvas::SetTop(myButton1, 50);
myButton1->Content = "Canvas.Top=50";
Canvas::SetBottom(myButton2, 50);
myButton2->Content = "Canvas.Bottom=50";
Canvas::SetLeft(myButton3, 50);
myButton3->Content = "Canvas.Left=50";
Canvas::SetRight(myButton4, 50);
myButton4->Content = "Canvas.Right=50";

// Add Buttons to the Canvas' Children collection
myCanvas->Children->Add(myButton1);
myCanvas->Children->Add(myButton2);
myCanvas->Children->Add(myButton3);
myCanvas->Children->Add(myButton4);

// Add the Canvas as the lone Child of the Border
myBorder->Child = myCanvas;

// Add the Border as the Content of the Parent Window Object
mainWindow->Content = myBorder;
mainWindow->Show();
C# 
// Create the application's main window
mainWindow = new Window ();
mainWindow.Title = "Canvas Attached Properties Sample";

// Add a Border
Border myBorder = new Border();
myBorder.HorizontalAlignment = HorizontalAlignment.Left;
myBorder.VerticalAlignment = VerticalAlignment.Top;
myBorder.BorderBrush = Brushes.Black;
myBorder.BorderThickness = new Thickness(2);

// Create the Canvas
Canvas myCanvas = new Canvas();
myCanvas.Background = Brushes.LightBlue;
myCanvas.Width = 400;
myCanvas.Height = 400;

// Create the child Button elements
Button myButton1 = new Button();
Button myButton2 = new Button();
Button myButton3 = new Button();
Button myButton4 = new Button();

// Set Positioning attached properties on Button elements
Canvas.SetTop(myButton1, 50);
myButton1.Content = "Canvas.Top=50";
Canvas.SetBottom(myButton2, 50);
myButton2.Content = "Canvas.Bottom=50";
Canvas.SetLeft(myButton3, 50);
myButton3.Content = "Canvas.Left=50";
Canvas.SetRight(myButton4, 50);
myButton4.Content = "Canvas.Right=50";

// Add Buttons to the Canvas' Children collection
myCanvas.Children.Add(myButton1);
myCanvas.Children.Add(myButton2);
myCanvas.Children.Add(myButton3);
myCanvas.Children.Add(myButton4);

// Add the Canvas as the lone Child of the Border
myBorder.Child = myCanvas;

// Add the Border as the Content of the Parent Window Object
mainWindow.Content = myBorder;
mainWindow.Show ();
Visual Basic 
WindowTitle = "Attached Properties Sample"
' Add a Border
Dim myBorder As New Border()
myBorder.HorizontalAlignment = Windows.HorizontalAlignment.Left
myBorder.VerticalAlignment = Windows.VerticalAlignment.Top
myBorder.BorderBrush = Brushes.Black
myBorder.BorderThickness = New Thickness(2)

' Create a Canvas as the root Panel
Dim myCanvas As New Canvas()
myCanvas.Background = Brushes.LightBlue
myCanvas.Width = 400
myCanvas.Height = 400

' Create the child Button elements
Dim myButton1 As New Button()
Dim myButton2 As New Button()
Dim myButton3 As New Button()
Dim myButton4 As New Button()

' Set Positioning attached properties on Button elements
Canvas.SetTop(myButton1, 50)
myButton1.Content = "Canvas.Top=50"
Canvas.SetBottom(myButton2, 50)
myButton2.Content = "Canvas.Bottom=50"
Canvas.SetLeft(myButton3, 50)
myButton3.Content = "Canvas.Left=50"
Canvas.SetRight(myButton4, 50)
myButton4.Content = "Canvas.Right=50"

' Add Buttons to the Canvas' Children collection
myCanvas.Children.Add(myButton1)
myCanvas.Children.Add(myButton2)
myCanvas.Children.Add(myButton3)
myCanvas.Children.Add(myButton4)

' Add the Canvas as the lone Child of the Border
myBorder.Child = myCanvas
Me.Content = myBorder
XAML 
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" WindowTitle="Canvas Attached Properties Sample">
  <Border HorizontalAlignment="Left" VerticalAlignment="Top" BorderBrush="Black" BorderThickness="2">
    <Canvas Background="LightBlue" Width="400" Height="400">
      <Button Canvas.Top="50">Canvas.Top="50"</Button>
      <Button Canvas.Bottom="50">Canvas.Bottom="50"</Button>
      <Button Canvas.Left="50">Canvas.Left="50"</Button>
      <Button Canvas.Right="50">Canvas.Right="50"</Button>
    </Canvas>
  </Border>    
</Page>
Platforms

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

Version Information
See Also
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