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You can monitor and collect coverage data from .NET managed code during manual or automated functional tests performed on a running web application that is deployed on IIS server. You can also send coverage data and test results to DTP. The application coverage information can be displayed in the DTP Coverage Explorer (see the "Coverage Explorer" chapter in the DTP user manual), which provides insights about how well the application is tested, as well as the quality of your tests.

Prerequisites

The following components are required for collecting coverage:

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• You can download coverage information that was collected in a test session. Coverage data collected when no test session was active cannot be downloaded.
• If multiple users are simultaneously accessing the same web application, the coverage data they collect may be mixed. To ensure that coverage is properly associated with individual users, the multiuse mode must be enabled (see Collecting Coverage from Multiple Users).
• The HTTP or HTTPS protocols are required to enable the multiuser mode, as the user-specific information must be provided within the HTTP header.
• In the multiuser mode, collecting coverage for WCF-based applications requires that they have the ASP.NET compatibility mode enabled.
• In the multiuser mode, the "default" user (the user who has not specified their ID) may collect extra coverage information from other users who are accessing the same web application.
• In the multiuser mode, assigning coverage collected for multithreaded application to individual users is limited. Coverage data for child threads is not assigned to the user who is actually accessing the application, but to the "default" user.
• Coverage data collected web initialization is not assigned to a specific user, but to the "default" user.
• The application coverage scope file cannot be used for WebSite projects as they may get recompiled by IIS Server and change the name of the target assembly. Scope files can be safely used for Web Applications.
• dotTEST does not support collecting coverage for .NET Core web-based applications. As a workaround, use the the coverage.exe tool, as described in Application Coverage for Standalone Applications.