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simon
Asked: 2020-01-18 10:50:17 +0800 CST 2020-01-18 10:50:17 +0800 CST

convert string to Double to get subtotal

  • 772

I'm new to c# and I have the following code:

 using System;

public class Program
{
    public static void Main()

    {

        int precio;
        int cantidadarticulo;
        int subtotal;
        int siniva;
        int coniva;
        int total;

     Console.WriteLine("dame nombre : ");
     string nombrepedido = Console.ReadLine();

     Console.WriteLine("dame precio : ");
     string preciopedidos = Console.ReadLine();
     precio = Convert.ToInt32(preciopedidos);


     Console.WriteLine("dame cantidad de cualquier articulo : ");
     string cantidadarticulopedido = Console.ReadLine();
     cantidadarticulo = Convert.ToDouble(cantidadarticulopedido);


        //calcular subtotal
        subtotal = cantidadarticulo/16;

and if you see in this next line I'm using toDouble to convert a String to a double to get the subtotal.

 cantidadarticulo = Convert.ToDouble(cantidadarticulopedido);

For that I am using this c# code:

Convert.ToDouble Method (String)

source of the above code

this is the complete code:

 //+===================================================================
//
//   Acerca del programa : 
//
//   3. Elabore un programa que pida el nombre, el precio y la cantidad de cualquier artículo (sin iva); 
//   y que después informe de cuanto tiene que pagar el usuario por dicho producto: subtotal sin iva, iva y total.  
//
//  Autor del codigo : Gilberto Quintero Armenta
//  codigo en github ( el codigo en linea ) :

//  Herramienta que use para codificar el codigo c# : https://dotnetfiddle.net
//
//
//
//
//
//+===================================================================

using System;

public class Program
{
    public static void Main()

    {

        int precio;
        int cantidadarticulo;
        int subtotal;
        int siniva;
        int coniva;
        int total;

     Console.WriteLine("dame nombre : ");
     string nombrepedido = Console.ReadLine();

     Console.WriteLine("dame precio : ");
     string preciopedidos = Console.ReadLine();
     precio = Convert.ToInt32(preciopedidos);


     Console.WriteLine("dame cantidad de cualquier articulo : ");
     string cantidadarticulopedido = Console.ReadLine();
     cantidadarticulo = Convert.ToDouble(cantidadarticulopedido);


        //calcular subtotal
        subtotal = cantidadarticulo/16;




        Console.WriteLine("subtototal: ");
        Console.WriteLine("sin iva: ");
        Console.WriteLine("total: ");



    }
}

I do not understand why it does not work if in the documentation it indicates that I must use toDouble to convert a string to Double, where could my error be?

c#

2 Answers

  1. Best Answer

    Well, it's simple, I'll explain:

    You are declaring an integer

        int cantidadarticulo;

    You are trying to assign a double to an integer.

         cantidadarticulo = Convert.ToDouble(cantidadarticulopedido);

    To fix it, declare itemQuantity as double;

    So:

    double cantidadarticulo;

    Note: I suggest you declare your int as a decimal, since for example a price can have decimals. as well as the subtotal

    • 3

  2. Although your question has already been answered, I would like to add some suggestions that allow you to write C# code that is more readable.

    To begin with, in C# it is not common to declare variables at the beginning of the Main(), as is usually done in C or C++, but it is common practice to declare variables when using them, as for example you did in the line: string nombrepedido = Console.ReadLine();. Similarly, instead of declaring Main()the variable at the beginning int cantidadarticuloand then writing:

    Console.WriteLine("dame cantidad de cualquier articulo : ");
string cantidadarticulopedido = Console.ReadLine();
cantidadarticulo = Convert.ToDouble(cantidadarticulopedido);

    The following code is more readable:

    Console.WriteLine("dame cantidad de cualquier articulo : ");
string cantidadarticulopedido = Console.ReadLine();
int cantidadarticulo = Convert.ToDouble(cantidadarticulopedido);

    Writing in the above way would have made you notice your mistake of wanting to store a doublein a int, which is not allowed. If you use VS you will even notice that the program "complains" and gives you the error: " Cannot implicitly cast type doubletoint ".

    On the other hand, it is unnecessary to create extra type variables stringto use the Console.ReadLine(). Instead of writing:

    Console.WriteLine("dame precio : ");
string preciopedidos = Console.ReadLine();
precio = Convert.ToInt32(preciopedidos);

    I suggest you write more succinctly the above code as:

    Console.WriteLine("dame precio : ");
int precio = Convert.ToInt32(Console.ReadLine());

    The above is also common practice in C#.

    Finally, regarding the name of your variables. From what I understand, when your variable name is made up of two or more words, as is the case with cantidadarticulo, it is not recommended to write it all in lowercase, but rather to use the sub-hyphen (_)to separate each word or capitalize the first letter of each. word from the second. For example, in the case of the variable cantidadarticulo, it is better to write either cantidad_articuloor cantidadArticulo.

    • 0