Comparing a string and array

[Jxyden]

I am new to c# is there any simple way to compare the user's input to an array for an authentication system to a game?
thanks

 

[CodeMonkeyJ]

The problem appears to be that one of your strings is a string array (string[]). It's hard to say without seeing the actual code. But, the following is how you compare two strings.

string str1 = "Hello World!";
string str2 = "Hello World!";
if (str1 == str2)
{
    Console.WriteLine("equal");
} else
{
    Console.WriteLine("not equal");
}

 

[Jxyden]

The problem appears to be that one of your strings is a string array (string[]). It's hard to say without seeing the actual code. But, the following is how you compare two strings.

string str1 = "Hello World!";
string str2 = "Hello World!";
if (str1 == str2)
{
    Console.WriteLine("equal");
} else
{
    Console.WriteLine("not equal");
}

What i an trying to do is make a authentication system where you input a name and it looks at a array and sees if they can go in or not. When i try doing it like you have said it says it cant convert a string[] to a string

 

[CodeMonkeyJ]

By using the System.Linq namespace, arrays get a Contains function that can find a value inside them. At the top of the program, add

using System.Linq;

Then, we change our comparison:

string[] usernames = new string[]{ "user1", "user2" };
string user = "user1";
if (usernames.Contains(user))
{
    Console.WriteLine("user found");
} else
{
    Console.WriteLine("user not found");
}

 

[Jxyden]

By using the System.Linq namespace, arrays get a Contains function that can find a value inside them. At the top of the program, add

using System.Linq;

Then, we change our comparison:

string[] usernames = new string[]{ "user1", "user2" };
string user = "user1";
if (usernames.Contains(user))
{
    Console.WriteLine("user found");
} else
{
    Console.WriteLine("user not found");
}

I am now getting this error when trying to put “using system.linq

 

[CodeMonkeyJ]

I don't know that error off the top of my head, but you have to put the using statement way up at the top of the file.

 

[Jxyden]

How would you kane it into a statement just by putting
Using system.linq or not?

 

[CodeMonkeyJ]

The `using System.Linq` goes up at the top to import functions/etc so that they can be used. When it's imported, arrays get a Contain method for finding values within them. Below is my entire program.

using System;
using System.Linq;

namespace Stringcompare
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] usernames = new string[]{ "user1", "user2" };
            string user = "user1";
            if (usernames.Contains(user))
            {
                Console.WriteLine("user found");
            } else
            {
                Console.WriteLine("user not found");
            }
        }
    }
}