System.Format.Exception Input string was not in a correct format

Question

I am having some trouble when calling a method from class A in class B.

Here is the method being called in class B

 public double monthlyExpense
        {
            get
            {
                return RealEstateApp.GetExpenses();
            }

The method itself from class A is

public static double GetExpenses()
{
    double insurance;
    double taxes;
    double utilities;
    string inValue;

    inValue = _insurance;
    insurance = double.Parse(inValue);
    inValue = _tax;
    taxes = double.Parse(inValue);
    inValue = _utilities;
    utilities = double.Parse(inValue);
    return (insurance / 12 + taxes / 12 + utilities);

}

I get the exception a the insurance = double.Parse(inValue); line.

The _insurance etc variables are being read from various text boxes:

RealEstateApp._insurance = txtBoxInsurance.Text;
RealEstateApp._tax = txtBoxTax.Text;
RealEstateApp._utilities = txtBoxUtilities.Text;

Any help would be hugely appreciated.

This should be solvable by simply [using the debugger](http://msdn.microsoft.com/en-us/library/sc65sadd.aspx), IMO. — Uwe Keim, Apr 28 '14 at 04:42
Then it is the textbox. Check if you input it in the correct format. — Poomrokc The 3years, Apr 28 '14 at 04:43
@UweKeim I am a bit of noob to c# and programming in general so apologies if this is trivial. — Matt, Apr 28 '14 at 04:44
Easy way , before the line that gives error, call Messagebox.Show(inValue); and see if the value in the message box is the value you are looking for. — Poomrokc The 3years, Apr 28 '14 at 04:48
Okay upon further testing it looks like the data from the textboxes isn't being read and I am ending up with a 0 value using the TryParse method in the answer below. Any ideas why this may be? — Matt, Apr 28 '14 at 05:16
You must validate your inputs. What is this application? Web? Windows? — Paulo Morgado, Apr 28 '14 at 07:44

score 0 · Answer 1 · answered Apr 28 '14 at 05:00

0

You might have inserted wrong input like space or any other character in txtBoxInsurancetextbox firstly validate that textbox for double value then you will not get that exception.

answered Apr 28 '14 at 05:00

Mohini Mhetre

912
10
29

That in fact is the case - the data from the textboxes isn't being read and I am ending up with a 0 value using the TryParse method and an exception if using Parse. – Matt Apr 28 '14 at 05:28
Try this one. Convert.ToDouble(inVal); – Mohini Mhetre Apr 28 '14 at 06:45

Manish Parakhiya · Answer 2 · 2014-04-28T04:58:28.673

-1

You can use TryParse instead of parse method

 inValue = _insurance;
double.TryParse(inValue,out insurance);//this will assign double value to insurance variable 
inValue = _tax;
double.TryParse(inValue,out taxes);

This will try to parse string value to double value and return true or false if it success or fail.

edited Apr 28 '14 at 04:58

answered Apr 28 '14 at 04:44

Manish Parakhiya

3,732
3
22
25

1

-1 This hides the problem. doesn't solves it. – Sriram Sakthivel Apr 28 '14 at 04:44
Also this gives me a Cannot implicitly convert type bool to double error. – Matt Apr 28 '14 at 04:46
don't assign it to variable like this insurance =double.TryParse(inValue,out insurance ); – Manish Parakhiya Apr 28 '14 at 04:48

System.Format.Exception Input string was not in a correct format

2 Answers2