NATVIS File – What is .natvis file and how to open it?

NATVIS Files: Introduction

NATVIS files, short for Native Visualizer for Visual Studio, are XML-based configuration files used in Microsoft’s Visual Studio debugger. They define visualization rules for specific data structures and objects, allowing developers to customize how these entities are displayed in the debugger’s data visualization windows. NATVIS files enable enhanced debugging experiences by providing tailored representations of complex data structures, simplifying their comprehension and analysis.

Applications and Benefits

NATVIS files find applications in various scenarios. They can be used to:

• Enhance visualization of standard data types, such as arrays, lists, or trees, providing a more intuitive representation.
• Create custom visualizations for complex user-defined classes or data structures, enabling developers to understand the internal state of their code.
• Simplify debugging of generated code, such as code produced by compilers or code generators, by providing meaningful visualizations that simplify understanding the underlying data structures.
• Support debugging of third-party libraries or frameworks by defining visualization rules for their specific data types or objects.

Opening NATVIS Files

NATVIS files, also known as Natvis VC++ Debugger Visualization Files, are used for customizing the visualization of variables and data structures in the Microsoft Visual Studio debugger. To open a NATVIS file, follow these steps:

1. Open Visual Studio and navigate to the Debug menu.
2. Select Options and navigate to the Debugging category.
3. Under the Visualizer section, click on Edit User Customizations….
4. In the Debugger Visualizers dialog box, click on the Add button and select the NATVIS file you want to open.
5. The NATVIS file will be added to the list of loaded visualizers and will be applied when debugging any code that uses the corresponding data types or objects.

Creating and Editing NATVIS Files

NATVIS files are XML-based files that define visualization rules for specific data types, structs, and classes. To create a new NATVIS file, follow these steps:

1. Open a text editor, such as Notepad++ or Visual Studio Code.
2. Create a new XML file and save it with a .NATVIS file extension.
3. Enter the following basic structure into the file:
   xml
<?xml version="1.0" encoding="utf-8"?>
<AutoVisualizer xmlns="http://schemas.microsoft.com/vstudio/debugger/natvis/2010">
<Type Name="TypeName">
<DisplayString>DisplayString</DisplayString>
<!-- Additional visualization rules -->
</Type>
</AutoVisualizer>

4. Replace TypeName with the fully qualified name of the data type you want to visualize.
5. Replace DisplayString with a user-friendly name for the data type.
6. Add additional visualization rules, such as specifying custom expansions, colors, or tooltips, as needed.
7. Save the NATVIS file and add it to Visual Studio as described above.

What is a NATVIS File?

NATVIS (Natvis VC++ Debugger Visualization File) is an XML-based format designed primarily for extending the visualization capabilities of the Microsoft Visual C++ debugger (VC++ Debugger). These files enable developers to customize how specific data types appear in the debugger’s visualization windows, such as variable tooltips, watch windows, and disassemblers. By leveraging NATVIS, developers can significantly improve the readability, understandability, and overall debugging experience for custom or third-party data types.

Benefits and Features of NATVIS Files:

NATVIS files offer a multitude of benefits for developers. They allow for:

• Enhanced visualization of complex data structures, making it easier to interpret their contents.
• Custom formatting and display of data values, improving readability and reducing clutter.
• Display of additional information or diagnostic messages, providing context and assisting in debugging.
• Support for custom icons or colors, enabling visual identification of specific data types.
• Extension of existing debugger visualization mechanisms, allowing developers to adapt visualization to their specific needs.

Other Extensions