Create custom code and plug-ins for load tests
Applies to: 
Visual Studio 
Visual Studio for Mac
Note
This article applies to Visual Studio 2017. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here
A custom plug-in uses code that you write and attach to a load test or a web performance test. You can use the load test API and the web performance test API to create custom plug-ins for tests to expand to the built-in functionality. You can add multiple plug-ins to your load test.
Note
Web performance and load test functionality is deprecated. Visual Studio 2019 is the last version where web performance and load testing will be fully available. For more information, see the Cloud-based load testing service end of life blog post. To reduce the impact on users some minimum support is still available in Visual Studio 2022 Preview 3 or later. Users should also note web performance and load test functionality only supports Internet Explorer which is not available on Windows 11 and some versions of Windows 10. Read more on Internet Explorer Lifecycle policy.
Tasks
| Tasks | Associated topics |
|---|---|
| Create a custom plug-in for your load test: You can use load test API to create a custom plug-in to add more testing functionality to your load test. | - How to: Use the load test API - How to: Create a load test plug-in |
| Create a custom plug-in for your Web Performance test: You can use web performance test API to create a custom plug-in to add more testing functionality to your web performance test, including at the request level. You can also create a web service test. Additionally, you can create a web recorder plug-in that can modify a web performance test after it is recorded, but before it appears in the Web Performance Test Result Viewer. |
- How to: Use the web performance test API - How to: Create a web performance test plug-in - How to: Create a request-level plug-in - How to: Create a web service test - How to: Create a recorder plug-in |
| Add UI features to Web Performance Test Results Viewer: You can add more UI features to the Web Performance Test Results Viewer using a Visual Studio add-in. | - How to: Create a Visual Studio add-in for the web performance test results viewer |
| Create a custom HTTP body editor: You can create a custom editor to edit binary or string http XML responses from a web service. | - How to: Create a custom HTTP body editor for the web performance test editor |
Reference
Microsoft.VisualStudio.TestTools.LoadTesting