Hi Immanuel,
You can use class CL_GUI_FRONTEND_SERVICES and method GUI_UPLOAD to load data of excel in an internal table.
Now play with the internal table and generate a final internal table that you can use to display alv report. To display you can use below classes and methods.
cl_salv_table : For display
cl_salv_functions : For activating functions(User action) on output screen.
Thanks and Regards,
Satish
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