public ActionResult AddCalculation(Calculation calculation) { try { double[] results = Regex.Split(calculation.MathCal, @"-|\+|\*|\/").Select(x => Convert.ToDouble(x)).ToArray(); //if ((calculation.MathCal.Trim()).StartsWith(".")[1]) // textBox1.Text = "0" + textBox1.Text; string operation = Regex.Split(calculation.MathCal, @"[0-9]+")[1]; switch (operation) { case "+.": calculation.MathCal = $"{results[0]} {operation} {results[1]} = {results[0] + results[1]}"; break; case "-.": calculation.MathCal = $"{results[0]} {operation} {results[1]} = {results[0] - results[1]}"; break; case "*.": calculation.MathCal = $"{results[0]} {operation} {results[1]} = {results[0] * results[1]}"; break; case "/.": calculation.MathCal = $"{results[0]} {operation} {results[1]} = {results[0] / results[1]}"; break; case "+": calculation.MathCal = $"{results[0]} {operation} {results[1]} = {results[0] + results[1]}"; break; case "-": calculation.MathCal = $"{results[0]} {operation} {results[1]} = {results[0] - results[1]}"; break; case "*": calculation.MathCal = $"{results[0]} {operation} {results[1]} = {results[0] * results[1]}"; break; case "/": calculation.MathCal = $"{results[0]} {operation} {results[1]} = {results[0] / results[1]}"; break; default: break; } _calRepo.CreateCalculation(calculation); } catch (Exception) { calculation.MathCal = "NaN"; _calRepo.CreateCalculation(calculation); return(RedirectToAction("Index")); } return(RedirectToAction("Index")); }