Contains source code for shared classes and business objects (for example, ..cs, and .vb files) that you want to compile as part of your application. In a dynamically compiled Web site project, ASP.NET compiles the code in the App_Code folder on the initial
request to your application. Items in this folder are then recompiled when any changes are detected.
Code in the App_Code folder is referenced automatically in your application. The App_Code folder can contain subdirectories of files, which can include class files that in different programming languages. For more information, see
Shared Code Folders in ASP.NET Web Projects and
codeSubDirectories Element for compilation (ASP.NET Settings Schema).
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