---
title: "How to: Use Hit Testing with a Region"
ms.date: "03/30/2017"
dev_langs: 
  - "csharp"
  - "vb"
helpviewer_keywords: 
  - "hit tests [Windows Forms], using regions"
  - "regions [Windows Forms], hit testing"
ms.assetid: 3a4c07cb-a40a-4d14-ad35-008f531910a8
---
# How to: Use Hit Testing with a Region
The purpose of hit testing is to determine whether the cursor is over a given object, such as an icon or a button.  
  
## Example  
 The following example creates a plus-shaped region by forming the union of two rectangular regions. Assume that the variable `point` holds the location of the most recent click. The code checks to see whether `point` is in the plus-shaped region. If the point is in the region (a hit), the region is filled with an opaque red brush. Otherwise, the region is filled with a semitransparent red brush.  
  
 [!code-csharp[System.Drawing.MiscLegacyTopics#31](~/samples/snippets/csharp/VS_Snippets_Winforms/System.Drawing.MiscLegacyTopics/CS/Class1.cs#31)]
 [!code-vb[System.Drawing.MiscLegacyTopics#31](~/samples/snippets/visualbasic/VS_Snippets_Winforms/System.Drawing.MiscLegacyTopics/VB/Class1.vb#31)]  
  
## Compiling the Code  
 The preceding example is designed for use with Windows Forms, and it requires <xref:System.Windows.Forms.PaintEventArgs> `e`, which is a parameter of <xref:System.Windows.Forms.PaintEventHandler>.  
  
## See also

- <xref:System.Drawing.Region>
- [Regions in GDI+](regions-in-gdi.md)
- [How to: Use Clipping with a Region](how-to-use-clipping-with-a-region.md)
