you can do this way...
store formula in sql table
tblFormulas like below...
FormulaName FormulaEquation
Gain S.P. - C.P.
Loss C.P. - S.P.
Gain% (GAIN * 100)/C.P.
Loss% (LOSS * 100)/S.P
Selling Price (S.P) ((100 + GAIN%)/100)*C.P.
Now...
Write down code in .net
replace values of parameters in equations...
for e.g.
string Equation = "((100 + GAIN%)/100)*C.P.";
Equation = Equation.Replace("GAIN%", txtGainPer.text);
Equation = Equation.Replace("C.P.", txtCP.text);
Equation = Equation.Replace("S.P.", txtSP.text);
Equation = Equation.Replace("GAIN", txtGain.text);
Equation = Equation.Replace("LOSS", txtLoss.text);
Equation = "Select " + Equation;
NOTE : This code is vulnerable for
sql injection
TIP: to avoid this you can use
third party .net classes available for evaluate expressions OR can
write code for evaluate expressions your self
Hope this helped you.
Happy Coding!
:)