Different value from input

chipp_zanuff

i'm new to C# and i'm just doin a test proj... i wonder why this happened?

using System;

namespace test_cs
{
class Program
{
static double calc(double n, double m)
{
return (n * m);
}

    static void Main(string\[\] args)
    {
        Console.WriteLine("Welcome to calculator 1.0");
        Console.Write("Enter calculations:");
        double num1, num2;
        char oper;
        num1 = Convert.ToInt32(Console.Read());
        oper = Convert.ToChar(Console.Read());
        num2 = Convert.ToInt32(Console.Read());

        Console.WriteLine("{0} {1} {2}", num1, oper, num2);
        Console.ReadLine();
        Console.ReadLine();
    }

}

}

the result is: Imgur: The magic of the Internet[^] anybody can explain why? also, i actually wanna make input streaming like C++

std::cin >> num1 >> oper >> num2;

but haven't know how to do it in C#

OriginalGriff

Simple: COnsole.Read fetches a single character from eth input types by the user, and you are converting that to an integer - but Convert changes type, not value. The character '3' is not the same a a number 3 - it's a character with a particular value within a character set, which is actually 51 in decimal: http://www.asciitable.com/ What I'd suggest is you read it as a line:

string input = Console.ReadLine();

And then "break" that into separate token strings:

        Match m = Regex.Match(input, @"^(\\d+)(\[^\\d\])(\\d+)$");
        if (m.Success)
            {
            int a = int.Parse(m.Groups\[1\].Value);
            string op = m.Groups\[2\].Value;
            int b = int.Parse(m.Groups\[3\].Value);
            Console.WriteLine($"{a} {op} {b}");
            }

This also means that it will work if you enter 123+456

"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony AntiTwitter: @DalekDave is now a follower!

Lost User

51 is "3" in the ASCII table, 52 is "4". Console.Read reads a character and returns its ASCII value as an integer.

MSDN[^] wrote:

Returns Int32 The next character from the input stream, or negative one (-1) if there are currently no more characters to be read.

Bastard Programmer from Hell :suss: If you can't read my code, try converting it here[^] "If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.

chipp_zanuff

is there any simpler ways like C++? i can typed 9+3 and make input stream like this:

int num1, num2;
char opr;
std::cin >> num1 >> opr >> num2;

OriginalGriff

No. Using the Console to interface with the user is "old fashioned" and you won't be doing it for long anyway. C# was born into a Windows world, and was primarily designed to work in Windows apps. C++ was the child of C, and was born into a world where Windows was new and unpopular, so it was given much more text based user input focus, because it needed it way back then. In the modern world, even C++ apps very rarely use cin at all now!

"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony AntiTwitter: @DalekDave is now a follower!