C# - Using File.Exists, when file DOESN'T exist does not run the last else statement

Question

Super new to C#. I'm having an input get split and then find an ID from the pointsTarget var.

When the file DOES exist, it seems that the line

else if (File.Exists(filePath+userId+txt))
   returns true;

because it runs just fine and sets the argument "addPointsCompleted" to TRUE. It works just how I would expect. But when the file does NOT exist, I want it to return false and run the last else statement:

CPH.SetArgument("missing", "True");

and set "missing" to TRUE.

I feel like there is something wrong with the way I put in the if/else if/else statement because I get an error :

"System.IO.FileNotFoundException: Could not find file 'E:\Users\Troy\Documents\Stuff\PointNames\Test.txt'.

using System;
using System.IO;

public class CPHInline
{
    public bool Execute()
    {
        string rawInput = args["rawInput"].ToString();
        string[] split= rawInput.Split('+');
        var pointsTarget = split[0].ToString();
        var addPoints = split[1].ToString();
        CPH.LogInfo($"pointsTarget is {pointsTarget}");
        CPH.LogInfo($"addPoints is {addPoints}");
        var user = args["user"].ToString();
        CPH.SetArgument("pointsTarget", pointsTarget);
        string userPath = @"E:/Users/Troy/Documents/Stuff/PointNames/";
        string filePath = @"E:/Users/Troy/Documents/Stuff/PointIDs/";
        string txt = ".txt";
        var userId = File.ReadAllText(userPath+pointsTarget+txt);
        CPH.LogInfo($"userId is {userId}");

        if (user == pointsTarget)
        {
            CPH.SetArgument("corrupt", "True");
        }
        else if (File.Exists(filePath+userId+txt))
        {
            //DO THIS
            string fileName = filePath+userId+txt;
            string points = File.ReadAllText(fileName);
            int x = Convert.ToInt32(points);
            int y = Convert.ToInt32(addPoints);
            int sum = x + y;
            String newPoints;
            newPoints = sum.ToString();
            File.WriteAllText(fileName, newPoints);
            CPH.SetArgument("newPoints", newPoints);
            CPH.SetArgument("addPointsCompleted", "True");
        }
            
        else
        {
            //do this
            CPH.SetArgument("missing", "True");
        }

        return true;

     
    }
}

I tried looking around, but all the issues are from people where the file DOES exist and they can't find it. My problem is kind of the opposite.

Are you stepping through this with a debugger attached? If you're using Visual Studio, you should [learn to use the debugger](https://learn.microsoft.com/en-us/visualstudio/debugger/debugger-feature-tour?view=vs-2022) as it will allow you to step through this code line by line and examine all the values as you go, and that will help you learn exactly what it's doing and why. — mason, Jul 23 '22 at 14:45

score 2 · Accepted Answer · answered Jul 23 '22 at 14:46

I feel like there is something wrong with the way I put in the if/else if/else statement because I get an error "System.IO.FileNotFoundException: Could not find file 'E:\Users\Troy\Documents\Stuff\PointNames\Test.txt'.

This is a good opportunity for you to start familiarizing yourself with using a debugger to step through the code and observe its behavior. Because the problem has nothing to do with your if structure. It's happening before your if block. Right here:

var userId = File.ReadAllText(userPath+pointsTarget+txt);

Look at the error message. It's trying to read a file in the "PointNames" folder. Which is in your userPath variable:

string userPath = @"E:/Users/Troy/Documents/Stuff/PointNames/";

Which is only ever used in that one line of code that tries to read a file. And File.ReadAllText will throw a FileNotFoundException if the file is not found.

It seems you're already aware of how to check if a file exists. So why not apply that here? For example:

var userId = string.Empty;
if (File.Exists(userPath+pointsTarget+txt))
{
    userId = File.ReadAllText(userPath+pointsTarget+txt);
}
else
{
    // handle the error in some way
}

Now that you point it out I understand I was associating the error with the wrong file. I will also start learning how to use a debugger in the future. Thank you very much! — T. Navarro, Jul 23 '22 at 21:43

C# - Using File.Exists, when file DOESN'T exist does not run the last else statement

1 Answers1