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Graphics.IsVisible Method (Int32, Int32, Int32, Int32)

Indicates whether the rectangle specified by a pair of coordinates, a width, and a height is contained within the visible clip region of this Graphics.

Namespace:  System.Drawing
Assembly:  System.Drawing (in System.Drawing.dll)

Public Function IsVisible ( _
	x As Integer, _
	y As Integer, _
	width As Integer, _
	height As Integer _
) As Boolean


Type: System.Int32

The x-coordinate of the upper-left corner of the rectangle to test for visibility.

Type: System.Int32

The y-coordinate of the upper-left corner of the rectangle to test for visibility.

Type: System.Int32

Width of the rectangle to test for visibility.

Type: System.Int32

Height of the rectangle to test for visibility.

Return Value

Type: System.Boolean
true if the rectangle defined by the x, y, width, and height parameters is contained within the visible clip region of this Graphics; otherwise, false.

The following code example is designed for use with Windows Forms, and it requires PaintEventArgs e, which is a parameter of the Paint event handler. The code performs the following actions:

  • Creates a rectangular clipping region and sets it as the clipping region for the graphics object of the form using Replace.

  • Creates the location and size of two rectangles, one inside the clipping region and one outside.

  • Tests each of the rectangles for visibility and draws only the visible one.

The result is one small red rectangle, which is within the clip region.

Private Sub IsVisible4Int(ByVal e As PaintEventArgs)

    ' Set clip region. 
    Dim clipRegion As New [Region](New Rectangle(50, 50, 100, 100))
    e.Graphics.SetClip(clipRegion, CombineMode.Replace)

    ' Set up coordinates of rectangles. 
    Dim x1 As Integer = 100
    Dim y1 As Integer = 100
    Dim width1 As Integer = 20
    Dim height1 As Integer = 20
    Dim x2 As Integer = 200
    Dim y2 As Integer = 200
    Dim width2 As Integer = 20
    Dim height2 As Integer = 20

    ' If rectangle is visible, fill it. 
    If e.Graphics.IsVisible(x1, y1, width1, height1) Then
        e.Graphics.FillRectangle(New SolidBrush(Color.Red), x1, y1, _
        width1, height1)
    End If 
    If e.Graphics.IsVisible(x2, y2, width2, height2) Then
        e.Graphics.FillRectangle(New SolidBrush(Color.Blue), x2, y2, _
        width2, height2)
    End If 
End Sub

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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