Multiple IFs won't work

Question

I'm creating a Desktop application (console) for Windows, using C#.

This is my code:

namespace myapp
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello!");
            Console.WriteLine("Type 'exit' to exit!");
            string line = Console.ReadLine();
            if (line == "exit") {
                Environment.Exit(0);
            }
            if (line == "copyright") {
                Console.WriteLine("Copyright 2017 TIVJ-dev");
            }
        }
    }
}

If I type "exit", it works fine (I'm sure it does this Environment.Exit(0); action). But if I type "copyright", it does not work. I can see an empty line instead. I started with C# today, so my apologies if this is very beginner problem. I haven't found solution on the internet.

Screenshot:

Have you tried using a `Console.WriteLine()` for the "exit", as well, to see if it works as expected? — Dimitris Damilos, Sep 06 '17 at 10:08
also trim it before comparing like `if (line.Trim() == "copyright")` — Rahul, Sep 06 '17 at 10:10
running your program works as expected. It does output copyright, but you probably won't see it because the program finishes. — Riv, Sep 06 '17 at 10:11
Have you tried debugging it? There's nothing I can see that's wrong with your code - you should learn to use the debugger for something as simple as this. — Matt Hogan-Jones, Sep 06 '17 at 10:13
He told _There comes only empty line_. Program should be finished as expected, I think that is the problem. Why the program is still running. @Riv — Berkay Yaylacı, Sep 06 '17 at 10:15
@Matt Jones: I haqven't yet maked any versions. Just trying to get two IFs work, BY DEBUGGING! — Kuvaaja, Sep 06 '17 at 10:15
@Kuvaaja - I have no idea what you mean. Put a breakpoint in and step through it to see a) what the value of `line` is and b) whether the code executes the second `if` statement. No idea what "maked any versions" even means, and I think your caps lock is stuck. — Matt Hogan-Jones, Sep 06 '17 at 10:19
I've run this code and it works exactly as you have said it should work. Whatever issue you have, it's not in the code. — Matt Hogan-Jones, Sep 06 '17 at 10:22
@Tom. You published answer ´, but it's deleted. I can't mark it as solution. So the solution is else if. — Kuvaaja, Sep 06 '17 at 10:22
@Kuvaaja no it isn't. Your code in the question works. Whatever issue you have, it's not code related. — Matt Hogan-Jones, Sep 06 '17 at 10:25
If this makes sense I can delete this question. What do you think? — Kuvaaja, Sep 06 '17 at 10:26

score 3 · Answer 1 · answered Sep 06 '17 at 10:11

3

I'm not sure in what way it doesn't work. It should run

Console.WriteLine("Copyright 2017 TIVJ-dev");

then immediately close the console window. Try putting another

Console.ReadLine();

at the end of Main().

answered Sep 06 '17 at 10:11

spodger

1,668
1
12
16

Works for me. Sorry. In what way is it "not working"? What actually happens? – spodger Sep 06 '17 at 10:14
@Kuvaaja, it is back sorry for that :) – Tom Sep 06 '17 at 10:22

Tom · Accepted Answer · 2017-09-06T10:46:05.537

1

You could use an else if statement;

   namespace myapp
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello!");
            Console.WriteLine("Type 'exit' to exit!");
            string line = Console.ReadLine();
            if (line == "exit")
            {
                Environment.Exit(0);
            }
            else if (line == "copyright") {
                Console.WriteLine("Copyright 2017 TIVJ-dev");
            }
        }
    }
}

Edit

By using an if/else this does the same as using multiple if statements however this is a more efficient way and make it easier when using break points.

edited Sep 06 '17 at 10:46

answered Sep 06 '17 at 10:19

Tom

12,928
2
15
31

1

What difference does this make at all to the original code? The original code **worked**. – Matt Hogan-Jones Sep 06 '17 at 10:26
Can people please advise why this answer is being down voted? else if is a vaild way of checking? – Tom Sep 06 '17 at 10:29
1

@Tom not the downvoter, but I assume it was because the original code is fine and should work, the OP had/has another issue completely. Your addition doesn't change anything for this example – FakeCaleb Sep 06 '17 at 10:32
1

@Tom if/else probably more efficient, but aside from that it does the same thing as OP's original code. Can't see how it would solve the problem – Riv Sep 06 '17 at 10:33
1

@Kuvaaja I don't know how many more times I can say this, but the problem is not in your code. Your original code worked. Considering that the first if statement would **terminate the process** I don't see how an `else if` can be considered to be any better. – Matt Hogan-Jones Sep 06 '17 at 10:34

score 0 · Answer 3 · answered Sep 06 '17 at 11:02

Try launching the application by pressing ctrl F5 in visual studio and seeing if it works. Alternatively click on debug->start without debugging.

Then write "copyright" and press enter.

What is probably happening is that the console is printing the line, then closing before you have a chance to see it. When you don't use the debugger the console stays open even once the application is finished.

score -1 · Answer 4 · answered Sep 06 '17 at 11:03

-1

Now everyone: Now this project works fine! Thanks for people who said add another Console.ReadLine. When I tested else if, I forgot there was that also. But now it works, so I try to close this. Thanks everyone!

answered Sep 06 '17 at 11:03

Kuvaaja

51
12

Multiple IFs won't work

4 Answers4