Input string was not in correct format

Question

static void Main(string[] args)
{
    //read in the file
    StreamReader convert = new StreamReader("../../convert.txt");

    //define variables
    string line = convert.ReadLine();
    int conversion;
    int numberIn;
    float conversionFactor;

    Console.WriteLine("Enter the conversion in the form (amount,from,to)");
    String inputMeasurement = Console.ReadLine();
    string[] inputMeasurementArray = inputMeasurement.Split(',');

    while (line != null)
    {
        string[] fileMeasurementArray = line.Split(',');
        if (fileMeasurementArray[0] == inputMeasurementArray[1])
        {
            if (fileMeasurementArray[1] == inputMeasurementArray[2])
            {
                Console.WriteLine("{0}", fileMeasurementArray[2]);
            }
        }

        line = convert.ReadLine();

        //convert to int
        numberIn = Convert.ToInt32(inputMeasurementArray[0]);
        conversionFactor = Convert.ToInt32(fileMeasurementArray[2]);

        conversion = (numberIn * conversionFactor);
    }

    Console.ReadKey();
}

On the line conversionFactor = Convert.ToInt32(fileMeasurementArray[2]); , I am getting an error saying "Input string was not in correct format". Please help!

The text file consists of the following:

ounce,gram,28.0
pound,ounce,16.0
pound,kilogram,0.454
pint,litre,0.568
inch,centimetre,2.5
mile,inch,63360.0

Answer 1

According to the line of the text file, fileMeasurementArray[2] will be 28.0 pound . This cannot be converted to an int. You should remove the string and keep only the number 28.0 .

UPDATE : the question was updated and the line of text file corrected. So my previous answer does'nt make sense anymore.

The problem occurs probably because you are trying to convert a float to an int.

Answer 2

You are trying to convert a float to an int.

Define conversionFactor as a double

also the variable conversion needs to be a double aswell.

like so

using System;
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using System.IO;

namespace measurementConverter { 
    class Program 
    { 
        static void Main(string[] args) 
        {  //read in the file 
            StreamReader convert = new StreamReader("../../convert.txt");

            //define variables
            string line = convert.ReadLine();
            double conversion;
            int numberIn;
            double conversionFactor;

            Console.WriteLine("Enter the conversion in the form (amount,from,to)");
            String inputMeasurement = Console.ReadLine();
            string[] inputMeasurementArray = inputMeasurement.Split(',');

            while (line != null)
            {
                string[] fileMeasurementArray = line.Split(',');
                if (fileMeasurementArray[0] == inputMeasurementArray[1])
                {
                    if (fileMeasurementArray[1] == inputMeasurementArray[2])
                    {
                        Console.WriteLine("{0}", fileMeasurementArray[2]);
                    }
                }

                line = convert.ReadLine();

                //convert to int
                numberIn = Convert.ToInt32(inputMeasurementArray[0]);
                conversionFactor = Convert.ToDouble(fileMeasurementArray[2]);

                conversion = (numberIn * conversionFactor);
            }



            Console.ReadKey();


        }
    }
}

Answer 3

'28.0 pound' isn't an integer. I'd imagine that's where your problem lies.

Answer 4

numberIn and conversionFactor are floats, not Ints. Use:

float numberIn;
float conversionFactor;
...

//convert to float
numberIn = Convert.ToSingle(inputMeasurementArray[0]);
conversionFactor = Convert.ToSingle(fileMeasurementArray[2]);