The reason that Function Libraries are missing is that API Test uses C# as its scripting language, which is compiled and not interpreted language as compared to VBScript. Hence all your code will have to be compiled before it can be executed.

The UFT API equivalent would be the .dll files you can create with the help of Microsoft Visual Studio and add references to the same to your solution. The DLL is supposed you added references to some dll stored on your local drive.

Hope this helps in a better understanding of the working of the tool and understanding the difference between code sharing approaches of GUI and API.

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