Well, i see now why this command doesn't work for me!!
Actually, my inputfield takes his values from an Xls file (to avoid losses of values, due to the inputfield issue: when adding some lines, the input field keeps it position and does not work as it should! i guess you understand what i m talking about.), and when i execute the macro, it takes the last known value since last reload and does not force it to zero as it work in your example when their is no source for this inputfield.
So because of that, i can't find any good command to force my input field value to be 0. any ideas?