C#•12mo ago

input file error

when reading numbers in my input file, i convert them to integers and assign specific numbers to a variable such as

uint x = Convert.ToUInt32(nextItem[0]);
uint y = Convert.ToUInt32(nextItem[1]);
uint z = Convert.ToUInt32(reader.ReadLine());

uint x = Convert.ToUInt32(nextItem[0]);
uint y = Convert.ToUInt32(nextItem[1]);
uint z = Convert.ToUInt32(reader.ReadLine());

but i keep getting an error saying "'Input string was not in a correct format.'" i am unsure how to fix this because the input file is automatically a string, but converting it to an int is causing an error. I normally convert this way and have not had an issue

94 Replies

Kiel•12mo ago

two things: 1. it's better practice to use uint.(Try)Parse than Convert methods - those are older mostly reserved for legacy purposes 2. it doesn't hurt to separate the assignment and conversion so you can more easily see what the "input" is - if it's not the right format, it's not the right format, so you may need to find out why

DinnyOP•12mo ago

1. i understand, i will try. my prof taught us to code that way, so we've been using that in out coding. 2. could u elaborate please? :333

Kiel•12mo ago

string xString = nextItem[0];
uint x = Convert.ToUInt32(xString);
string yString = nextItem[1];
uint y = Convert.ToUInt32(yString);
string zString = reader.ReadLine();
uint z = Convert.ToUInt32(zString);

string xString = nextItem[0];
uint x = Convert.ToUInt32(xString);
string yString = nextItem[1];
uint y = Convert.ToUInt32(yString);
string zString = reader.ReadLine();
uint z = Convert.ToUInt32(zString);

assuming all your inputs are strings then when debugging you can inspect the values of xString, yString, zString

DinnyOP•12mo ago

ok lemme try,plz hold

ZacharyPatten•12mo ago

Is this a school assignment? Are you required to read your input file using a StreamReader? You could probably make your life much easier by using JSON serialization & deserialization instead of coding your own parser

DinnyOP•12mo ago

yes this is a school assignment my prof is very old school and encourages us to code this way :/// i just tried and got the same error I'll look up the try parse functuion function

ZacharyPatten•12mo ago

don't just ignore the error, what does the error say?

DinnyOP•12mo ago

im not that's why im doing try parse instead of convertto "input string was not in correct format"

ZacharyPatten•12mo ago

and what does that error mean to you? what is it telling you?

DinnyOP•12mo ago

i believe it's something to do on my part with the concersion because the input file is read as one big string in the past i've ive convertto to convert to an int but thats not working here used*

ZacharyPatten•12mo ago

instead of "i bleive..." you should check put a breakpoint

DinnyOP•12mo ago

well yeah that's why im here i've checked and ran into tjat error so now im trying the try parse

ZacharyPatten•12mo ago

that likely won't help put a breakpoint

DinnyOP•12mo ago

but he never taught us that :///

ZacharyPatten•12mo ago

on the line that is throwing the error

DinnyOP•12mo ago

i did and it gave me the error i told u :///

ZacharyPatten•12mo ago

putting breakpoints and debugging is a vital skill you need to learn as a software developer so time to start learning it 🙂 I'll share an example

DinnyOP•12mo ago

i am trying and it's hard :/// yes plz my tutor was teaching me a bit of how to debug , which has helped me a lot in c++ but i admit i am struggling more with c#

ZacharyPatten•12mo ago

ZacharyPatten•12mo ago

see the red dot on the left side? that is a "breakpoint" you click there to place breakpoints

DinnyOP•12mo ago

yes i know

ZacharyPatten•12mo ago

and you can click break points to remove them

DinnyOP•12mo ago

i used those ik how to dp that part by using those is where i foud my error bc i was debugging i came to that error if that makes sense im just now struggling to fix it

ZacharyPatten•12mo ago

then when you run the code, it will stop at the break point and you can hover your mouse over variables and such to see their values

ZacharyPatten•12mo ago

in this case, I am trying to convert/parse myString into an int but the value of myString is "cat" and that isn't valid for an int so it will throw the same error you are seeing

DinnyOP•12mo ago

ohh okay i see what ur saying

ZacharyPatten•12mo ago

now, in your code, put a breakpoint and tell us what your string looks like that you are trying to convert into a Uint

DinnyOP•12mo ago

the there's a header in my file thats "P3" that's suppose to stay a string otherwise the rest of the file is numbers i have a feeling it's trying to convert that one moment plz turns out my feeling was correct lemme try to fix plz hold i keep running into the same error it keeps trying to convert a string of words to an int but im not understanding how bc it should be moving on to the next line it's just staying on the first

ZacharyPatten•12mo ago

it will move on to the next line when you call ReadLine() are you calling ReadLine() multiple times? can you share your code and maybe your input file?

DinnyOP•12mo ago

yes one moment

 string? p = reader.ReadLine();
 uint x = Convert.ToUInt32(nextItem[0]);
 uint y = Convert.ToUInt32(nextItem[1]);
 uint z = Convert.ToUInt32(reader.ReadLine());
 

 List<Pixel> pixels = new List<Pixel>((int)(x * y));

 string? p = reader.ReadLine();
 uint x = Convert.ToUInt32(nextItem[0]);
 uint y = Convert.ToUInt32(nextItem[1]);
 uint z = Convert.ToUInt32(reader.ReadLine());
 

 List<Pixel> pixels = new List<Pixel>((int)(x * y));

DinnyOP•12mo ago

ScrambledFlag_1_1.pp...

ZacharyPatten•12mo ago

that isn't your full code where are you defining nextItem?

DinnyOP•12mo ago

oh i thought u meant the portion i was messing up on one moment

DinnyOP•12mo ago

MainProgram.cs

DinnyOP•12mo ago

do u need my other files too or no @ZP ░▒▓█├■̶˾̶͞■┤█▓▒░

ZacharyPatten•12mo ago

not yet. trying to get you an example

DinnyOP•12mo ago

okay sorry, take ur time

ZacharyPatten•12mo ago

static void Main()
{
    List<Color> pixels = [];
    using StreamReader reader = new("ScrambledFlag_1_1.ppm");
    reader.ReadLine(); // skip "P3" header line
    string sizeLine = reader.ReadLine()!; // read the "XXX YYY" size line
    string[] sizeSplits = sizeLine.Split(' ', StringSplitOptions.RemoveEmptyEntries);
    int size1 = int.Parse(sizeSplits[0]);
    int size2 = int.Parse(sizeSplits[1]);
    int length = size1 * size2;
    for (int i = 0; i < length; i++)
    {
        int red1 = int.Parse(reader.ReadLine()!);
        int blue1 = int.Parse(reader.ReadLine()!);
        int green1 = int.Parse(reader.ReadLine()!);

        pixels.Add(Color.FromArgb(red1, green1, blue1));
    }
    //UnscrambleMachine.Unscramble(pixels);
    using StreamWriter writer = new("UnscrambledFlag.ppm", false);
    //writer.WriteLine(p);
    //writer.WriteLine(x + " " + y);
    //writer.WriteLine(z);
    //for (int i = 0; i < pixels.Count; i++)
    //{
    //    writer.WriteLine(pixels[i].ToString());
    //}
}

static void Main()
{
    List<Color> pixels = [];
    using StreamReader reader = new("ScrambledFlag_1_1.ppm");
    reader.ReadLine(); // skip "P3" header line
    string sizeLine = reader.ReadLine()!; // read the "XXX YYY" size line
    string[] sizeSplits = sizeLine.Split(' ', StringSplitOptions.RemoveEmptyEntries);
    int size1 = int.Parse(sizeSplits[0]);
    int size2 = int.Parse(sizeSplits[1]);
    int length = size1 * size2;
    for (int i = 0; i < length; i++)
    {
        int red1 = int.Parse(reader.ReadLine()!);
        int blue1 = int.Parse(reader.ReadLine()!);
        int green1 = int.Parse(reader.ReadLine()!);

        pixels.Add(Color.FromArgb(red1, green1, blue1));
    }
    //UnscrambleMachine.Unscramble(pixels);
    using StreamWriter writer = new("UnscrambledFlag.ppm", false);
    //writer.WriteLine(p);
    //writer.WriteLine(x + " " + y);
    //writer.WriteLine(z);
    //for (int i = 0; i < pixels.Count; i++)
    //{
    //    writer.WriteLine(pixels[i].ToString());
    //}
}

there is an example that seems to work with the input file you provided you don't need to make both a file stream and a stream reader. you can just directly make the stream reader. also you want to use using in front of the stream reader. that is better than closing it later because it really needs to be in a try-catch and using "using" will do that for you you had multiple loops and things, but you didn't need som eof the extra stuff you had also, you can just change "Color" back to "Pixel" from my example. I didn't have your "Pixel" class so I just used System.Drawing.Color as an alternative

DinnyOP•12mo ago

I have to keep my stream reader and writer the same because that how my prof wants us to do it

ZacharyPatten•12mo ago

tell him to fuck off

DinnyOP•12mo ago

LMAOOOO im sorry he's very old fashioned :////

ZacharyPatten•12mo ago

seriously though. he shouldn't count off points if you use proper coding practices. if he did I would complain to your school abot that

DinnyOP•12mo ago

i doubt he would, but for now, i'd rather stick to what he taught us because, as amazing of an example it is, there's a lot of new stuff i am not familiar with and I don't wanna confuse myself

ZacharyPatten•12mo ago

does my example make sense?

DinnyOP•12mo ago

im still reading it, plz hold what's the "!" for in the 7th line

ZacharyPatten•12mo ago

that is a null forgiving operator you don't need it it tells the compiler to ignore a potential null value what version of C# are you using

DinnyOP•12mo ago

visual studios is version 17.7.4 and my .NET version is 4.8.04084

ZacharyPatten•12mo ago

you are using old stuff that is .NET Framework that is now legacy ".NET" is the new stuff ".NET Framework" is old and legacy

DinnyOP•12mo ago

it is .NET framework sorry i left out the framework part i didn’t realize there was a difference

ZacharyPatten•12mo ago

since this is a school assignment for an asshole of a teacher... you are probably stuck using the old shit... but I'm just trying to inform you that you really shouldnt' be using it anymore

DinnyOP•12mo ago

😭😭😭 ur not the only one hoenstly i’ve gotten help multiple times and they’ve told me the same thing a lot of what he teaches isn’t even in use anymore it suck’s but he’s the only c# prof my college has :/

ZacharyPatten•12mo ago

how goes on understanding my example? do you need me to convert it back to .NET Framework? what can I do to help you understand it?

DinnyOP•12mo ago

yes plz, could u do that i’m trying to compare it to my own code i think i get the gist but i just wanna make sure i apologize if this is such a hassle

ZacharyPatten•12mo ago

I coded it using .NET 8, which came out last month and has several features you don't have in that older version One sec I'll back port it

DinnyOP•12mo ago

tysm

ZacharyPatten•12mo ago

class Pixel
{
    public int Red { get; set; }
    public int Green { get; set; }
    public int Blue { get; set; }

    public Pixel(int red, int green, int blue)
    {
        Red = red;
        Green = green;
        Blue = blue;
    }
}

static void Main()
{
    List<Pixel> pixels = new List<Pixel>();
    using (StreamReader reader = new StreamReader("ScrambledFlag_1_1.ppm"))
    {
        reader.ReadLine(); // skip "P3" header line
        string sizeLine = reader.ReadLine(); // read the "XXX YYY" size line
        string[] sizeSplits = sizeLine.Split(' ');
        int size1 = int.Parse(sizeSplits[0]);
        int size2 = int.Parse(sizeSplits[1]);
        int length = size1 * size2;
        for (int i = 0; i < length; i++)
        {
            int r = int.Parse(reader.ReadLine());
            int g = int.Parse(reader.ReadLine());
            int b = int.Parse(reader.ReadLine());
            pixels.Add(new Pixel(r, g, b));
        }
    }
    //UnscrambleMachine.Unscramble(pixels);
    using (StreamWriter writer = new StreamWriter("UnscrambledFlag.ppm", false))
    {
        //writer.WriteLine(p);
        //writer.WriteLine(x + " " + y);
        //writer.WriteLine(z);
        //for (int i = 0; i < pixels.Count; i++)
        //{
        //    writer.WriteLine(pixels[i].ToString());
        //}
    }
}

class Pixel
{
    public int Red { get; set; }
    public int Green { get; set; }
    public int Blue { get; set; }

    public Pixel(int red, int green, int blue)
    {
        Red = red;
        Green = green;
        Blue = blue;
    }
}

static void Main()
{
    List<Pixel> pixels = new List<Pixel>();
    using (StreamReader reader = new StreamReader("ScrambledFlag_1_1.ppm"))
    {
        reader.ReadLine(); // skip "P3" header line
        string sizeLine = reader.ReadLine(); // read the "XXX YYY" size line
        string[] sizeSplits = sizeLine.Split(' ');
        int size1 = int.Parse(sizeSplits[0]);
        int size2 = int.Parse(sizeSplits[1]);
        int length = size1 * size2;
        for (int i = 0; i < length; i++)
        {
            int r = int.Parse(reader.ReadLine());
            int g = int.Parse(reader.ReadLine());
            int b = int.Parse(reader.ReadLine());
            pixels.Add(new Pixel(r, g, b));
        }
    }
    //UnscrambleMachine.Unscramble(pixels);
    using (StreamWriter writer = new StreamWriter("UnscrambledFlag.ppm", false))
    {
        //writer.WriteLine(p);
        //writer.WriteLine(x + " " + y);
        //writer.WriteLine(z);
        //for (int i = 0; i < pixels.Count; i++)
        //{
        //    writer.WriteLine(pixels[i].ToString());
        //}
    }
}

that compiles in .NET Framework you can remove the class Pixel {...} I just added that since I don't have your class

ZacharyPatten•12mo ago

if I put a break point after the using for the stream reader, you can see that the list of pixels has 1215000 items in it because 1350 * 900 = 1215000 (1350 and 900 are the sizes listed in the file on line #2) If you need to go back to the code your teacher wanted for the stream reader/writer... the reason why I moved them around is because in general you should only keep files open while you need them the way you were doing it, your file was open the entire time the program is running but you should only keep the input file open while you are reading it (the first half of your app) and you should only keep the output file open while you are writing to it (the 2nd part of your app) keeping files open for longer than necessary causes issues

DinnyOP•12mo ago

ok lemme read up and make some adjustments one moment plz

ZacharyPatten•12mo ago

heads up... I may have swapped green and blue compared to your code. in general most graphics libraries tend to use RGB, not RBG feel free to use RBG if necessary, but that is why I changed it 😛

DinnyOP•12mo ago

waitso for the "skipping header" part, i have

 string p = reader.ReadLine();

 string p = reader.ReadLine();

because my prof said we had to read it to let our program know we will be working with pixels and pictures i gotta get rid of that ? or just get rid of the left half

ZacharyPatten•12mo ago

you just need to skip past the first line of the file. the first line of the file you provided has "P3" which doesn't matter for us every time you call ReadLine it will progress the reader to the next line of the file one of the problems you had in your code is that you had two loops and that probably wasn't necessary:

while (!reader.EndOfStream)
{
    ...
    for (int i = 0; i < pixels.Count; i++)
    {

while (!reader.EndOfStream)
{
    ...
    for (int i = 0; i < pixels.Count; i++)
    {

you only really need one loop to loop through all the ints in the file

DinnyOP•12mo ago

but my prof does the "while !reader.EndOfStream" so we put that in our code im so sorry this is so lik extra 😭 idk y he teaches that way honestly i feel like i give ppl a stroke whenever they see how i have to code lmao

ZacharyPatten•12mo ago

using while (!reader.EndOfStream) is fine there are often multiple ways to do any task in code but what I'm getting at is that you only need one loop not two

DinnyOP•12mo ago

oh i have three loops the while loop to read the entire input file, the first for loop to read the pixels and add them to the list, and the last for loop to display the list in the input file

ZacharyPatten•12mo ago

Yes but you are misunderstanding loops when you put one loop inside another loop it is a "nested loop" you were nesting loops when at least for the output part of your code you should do that loop after the input loop finishes Did you try out my code? Did you get it to read in the entire input file?

DinnyOP•12mo ago

im still tweaking parts of my code to what you've shown me one moment ok that part is solved, but i am not getting that same error in my override ToString() method one sec

DinnyOP•12mo ago

Pixel.cs

DinnyOP•12mo ago

this is my pixel file the ToString() method at the bottom, I get the same error from earlier

ZacharyPatten•12mo ago

that is ugly... I'm assuming your teacher provided that code?

DinnyOP•12mo ago

i call this method at the end when displaying my pixel list

for (int i = 0; i < length; i++)
{
    writer.WriteLine(pixels[i].ToString());
}

for (int i = 0; i < length; i++)
{
    writer.WriteLine(pixels[i].ToString());
}

YES LMAOOO

ZacharyPatten•12mo ago

we don't make Get and Set methods in C#... that is a Java thing...

DinnyOP•12mo ago

apparently no one uses doc strings either ??

ZacharyPatten•12mo ago

C# has "properties" so we don't need getter and setter methods

DinnyOP•12mo ago

he also teaches java :/// according to him we do :///

ZacharyPatten•12mo ago

he should not be teaching C#...

DinnyOP•12mo ago

i feel like imma have to unlearn everything he's taught when i transfer to a 4 year uni :////

ZacharyPatten•12mo ago

can you elaborate on what error you are currently seeing? if the error is happening in the output, it should be a different error

DinnyOP•12mo ago

the same one from earlier, 'Input string was not in a correct format.'"

ZacharyPatten•12mo ago

can you get a screenshot of where the error is being thrown?

DinnyOP•12mo ago

yes plz hold

DinnyOP•12mo ago

ZacharyPatten•12mo ago

o... you have ")" when you need "}" take a closer look 😉

DinnyOP•12mo ago

-__- i need a cig after this😭 not actua;;y but oml it really be the littlest things i swear

ZacharyPatten•12mo ago

you will get used to finding stuff like that it never stops 😛 you will always make little typos and crap while coding but as you improve you will get better and catching it

DinnyOP•12mo ago

i remeber i spent an error when i simply needed to make something a word lowercase instead of capitilized 😭 ok the code compiled imma check my output file so it compiled but this def is NOT the dutch flag LMAOOO i gott tweak my unscrambler file

ZacharyPatten•12mo ago

lol.... it sounds like your original issue of how to handle the input and output is resolved?

DinnyOP•12mo ago

yes it is ! tysm like real kitty really**

ZacharyPatten•12mo ago

do you have any questions about the code?

DinnyOP•12mo ago

like i’m truly grateful for ur help uhhh i honestly might 💀💀💀 just gimme one second i did learn a lot from u tho !

DinnyOP•12mo ago

my unscramble file literally looks great, i did it with my school tutor

DinnyOP•12mo ago

idk how it's ending up like this'it should be solid red, then white, then blue

ZacharyPatten•12mo ago

I will need more info in order to help. did your teacher provide you some instructions explaining what about the input file is "scrambled" and therefore needs to be unscrambled? also can you share the code for your unscrambling method? --- I'll have to go offline for the night soon. I would recommend you close this help post since the original issue of handling the input and output is resolved (so other discord users don't have to skim this entire chat), but open a new help post for your unscrambling logic not working correctly. You will need to provide a lot of extra infor for us to help though.

DinnyOP•12mo ago

i understand ty ! i will

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input file error