VFP calculator uses _CALCVALUE and _CALCMEM system variables. You can use keyboard or mouse to operate it.

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>I thought it would be a good idea let the user to use the "Calculator Window" when he has to input a complex price. I activated the calculator and I could make a few operations as adding for example. By the moment I'm not insterested how bring the result. I'd like to know how can I manage the calculator with only a hand like a real calculator. Do you know any tips? VFP help says almost nothing about it.
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