Dear Amateur and Veteran Developers,
I'm a beginner who recently started learning C# a bit more seriously (I've already tipped my toes into the world of C# in high school, but now, I'm more serious about learning it). I've made a simple command prompt application as a homework for my High-level Programming Languages lesson at my university:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace HW_002_01
{
class Program
{
static void Main(string[] args)
{
Console.Write("Please enter the length of the triangle's a side (cm)! ");
double a;
bool a_if = double.TryParse(Console.ReadLine(), out a);
Console.Write("Please enter the length of the triangle's b side (cm)! ");
double b;
bool b_if = double.TryParse(Console.ReadLine(), out b);
Console.Write("Please enter the length of the triangle's c side (cm)! ");
double c;
bool c_if = double.TryParse(Console.ReadLine(), out c);
if (a_if == true && a > 0 && b > 0 && c > 0)
{
double res1 = a b;
if (res1 > c)
{
Console.WriteLine("Triangle equality is present.");
}
else
{
Console.WriteLine("Triangle equality is not present.");
}
}
else if (b_if == true && a > 0 && b > 0 && c > 0)
{
double res2 = a b;
if (res2 > c)
{
Console.WriteLine("Triangle equality is present.");
}
else
{
Console.WriteLine("Triangle equality is not present.");
}
}
else if (c_if == true && a > 0 && b > 0 && c > 0)
{
double ossz3 = a b;
if (res3 > c)
{
Console.WriteLine("Triangle equality is present.");
}
else
{
Console.WriteLine("Triangle equality is not present.");
}
}
else
{
Console.WriteLine("You cannot make a tringle with these numbers.");
}
Console.ReadKey();
}
}
}
This little program checks triangle equality in a triangle with the numbers that the user types in. It runs fine, but I just don't know how to make an error message about the program not being able to understand decimal fractions with a dot instead of a comma. This would be a nice cosmetic touch-up to my program to excuse my beginner-level spaghetti code.
I hope someone replies very soon.
CodePudding user response：
double.TryParse already check the number format by using your default culture. So if the dot doesnt exist in your culture number format, and a user inputs it instead of comma, double.TryParse returns false.
CodePudding user response：
I've written a method that will help you make sure that there is a comma and it depends on the read and the operation you did to read and then convert to double. Previously your reading line is:
bool a_if = double.TryParse(Console.ReadLine(), out a);
And now:
bool a_if = double.TryParse(isWithComma(Console.ReadLine()), out a);
In fact, the method will check if the comma is within the number, and if that will show an error message and the program will stop and I have added a red color to give more expression in the error, and at the same time it returns a string if the number is correct and does not contain a comma, then the program will complete without problems
This is the entire code after modification, and there is a variable (ossz3) that has shown me an error and I have modified it, please check it:
using System;
namespace HW_002_01
{
class Program
{
//New by: https://github.com/MohammadYAmmar
public static string isWithComma(string value)
{
if (value.Contains(","))
{
Console.ForegroundColor = ConsoleColor.Red;
Console.WriteLine("Error: cannot be used comma instead of a dot.");
Console.WriteLine("Please try again using the point (dot) for example 3.3");
System.Environment.Exit(0);
return value;//Won't happen
}
else
{
return value;
}
}
static void Main(string[] args)
{
Console.Write("Please enter the length of the triangle's a side (cm)! ");
double a;
bool a_if = double.TryParse(isWithComma(Console.ReadLine()), out a);
Console.Write("Please enter the length of the triangle's b side (cm)! ");
double b;
bool b_if = double.TryParse(isWithComma(Console.ReadLine()), out b);
Console.Write("Please enter the length of the triangle's c side (cm)! ");
double c;
bool c_if = double.TryParse(isWithComma(Console.ReadLine()), out c);
if (a_if == true && a > 0 && b > 0 && c > 0)
{
double res1 = a b;
if (res1 > c)
{
Console.WriteLine("Triangle equality is present.");
}
else
{
Console.WriteLine("Triangle equality is not present.");
}
}
else if (b_if == true && a > 0 && b > 0 && c > 0)
{
double res2 = a b;
if (res2 > c)
{
Console.WriteLine("Triangle equality is present.");
}
else
{
Console.WriteLine("Triangle equality is not present.");
}
}
else if (c_if == true && a > 0 && b > 0 && c > 0)
{
//Old
//double ossz3 = a b;
//New: Please check that the spelling is correct so that the code is correct for this variable as you wanted it to
double res3 = a b;
if (res3 > c)
{
Console.WriteLine("Triangle equality is present.");
}
else
{
Console.WriteLine("Triangle equality is not present.");
}
}
else
{
Console.WriteLine("You cannot make a tringle with these numbers.");
}
Console.ReadKey();
}
}
}
Good luck and have a good journey in learning C# :)