Btukfyl

Let's say, there are arrays of available item quantity given.

int [,] AvailableQuantity= new int[3,4]

{

    { 4, 5, 2, 3 },

    { 2, 7, 3, 4 },

    { 9, 3, 5, 6 }

};

If a user purchases 3 items of [0, 0], then the AvailableQuantity array must be updated with the current available quantity as below:

{

    { 1, 5, 2, 3 },

    { 2, 7, 3, 4 },

    { 9, 3, 5, 6 }

};

Again, if 2 items of, for example, [0, 1] are purchased, then the array should look like below:

{

    { 1, 3, 2, 3 },

    { 2, 7, 3, 4 },

    { 9, 3, 5, 6 }

};

The quantity has to be updated each time when any item is purchased and updated. Then, the array has to be saved in the text file as shown below when the application is closed.

1 3 2 3

2 7 3 4

9 3 5 6

How can this be performed?

The answer seems overly obvious, so I might be missing something. If the user selects to buy the item at 1,3, then you reduce the quantity at 1,3 accordingly. That is why you have two arrays, so you can re-use the indexes - or not?

However this design also seems flawed. Generally you do not put up two paralell arrays like that. Instead you make a custom class "Product" that has fields for price, quantity, name and everything else you may need later (like a name to display it with). And then you make array of that Product Products = new Products[10];. However you might still be before learning how to write classes.

As for saving the whole thing to a textfile: XML and CSV are common formats for such rather simple data. For little amounts of data, CSV might even be slightly more readable. But generally this should be a seperate question.

using System;

using System.IO;

using System.Text;



class Program



{

    /// <summary>

    /// Static Multidimensional Array what have products quantity.

    /// </summary>

    static int [,] AvailableQuantity = new int[3,4]

    {

        { 4, 5, 2, 3 },

        { 2, 7, 3, 4 },

        { 9, 3, 5, 6 }

    };



    /// <summary>

    /// Main Console Call.

    /// </summary>

    /// <param name="args"></param>

    public static void Main(string args)

    {



        string path = Environment.CurrentDirectory + "\file.txt";



        // TEST

        Purchase_Item(3, 0, 0);

        Purchase_Item(2, 0, 1);



        Save_File(path, Generate_String_File());



        System.Diagnostics.Process.Start("notepad.exe", path);



        Console.Write("Press any key to continue . . . ");

        Console.ReadKey(true);

    }



    /// <summary>

    /// Edit static int Multidimensional Array. (M.A)

    /// </summary>

    /// <param name="cuantity">The cuantity of the item what has ben purchased.</param>

    /// <param name="row">Row that you want to edit in the M.A.</param>

    /// <param name="column">Column that you want to edit in the M.A.</param>

    private static void Purchase_Item(int cuantity, int row, int column){



        try {



            if(row > AvailableQuantity.GetLength(0) || row < 0){

                Console.WriteLine("Row - Out of Range");

                return;

            }



            if(column > AvailableQuantity.GetLength(1) || column < 0){

                Console.WriteLine("Column - Out of Range");

                return;

            }



            int cuantity_in_row = AvailableQuantity[row, column];



            if(cuantity > cuantity_in_row){

                Console.WriteLine("Not enough items!");

                return;

            }



            AvailableQuantity[row, column] = cuantity_in_row - cuantity;



        } catch (Exception eX) {



            Console.WriteLine(eX.ToString());

        }



    }



    /// <summary>

    /// Generate string file, with the format (worst format ever).

    /// </summary>

    /// <returns>text that will be saved.</returns>

    private static string Generate_String_File(){



        string line = string.Empty;

        string full_text = string.Empty;



        for (int row = 0; row < AvailableQuantity.GetLength(0); row++) {



            line = string.Empty;



            for (int column = 0; column < AvailableQuantity.GetLength(1); column++) {



                line += AvailableQuantity[row, column].ToString() + " ";

            }



            line = line.Remove(line.Length-1);



            full_text += line + Environment.NewLine;

        }



        full_text = full_text.Remove(full_text.Length-1);



        return full_text;

    }



    /// <summary>

    /// Save the file at the asing path.

    /// </summary>

    /// <param name="path">location where will go the file.</param>

    /// <param name="text">text that will be included at the file.</param>

    private static void Save_File(string path, string text){



        try {



            File.WriteAllText(path, text);



        } catch (Exception eX) {



            Console.WriteLine(eX.ToString());

        }





    }



}

I'm not an expert, but i supouse that it has to be something like that...
Please do not kill me for do it, it's just the worst implemention for what do you want.