In Excel COM the range object exposes two dimensional array that can be used to create json quickly. In this article I will cover, how you can transpose entire selected range into an array and get a handy json.
This example covers Excel Addin which is VSTO (Visual studio tools for office) C# technology, however no need to surprise as I have plenty of examples where you can understand how you can create your own Excel Addin using C# Visual Studio
If I make selection for given data in excel, the code gives me output as given in next screenshot:
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