What is wrong with this following c# code just trying to find out Length and reverse of a given String

Question

I am just trying to find out the reverse and length of a string. Here is the snippet of the Code:

    Console.WriteLine("Please Enter your String: ");
        string InputString = Console.ReadLine();

        char[] String_Array = InputString.ToCharArray();
        int Length = 0;

        foreach (char c in String_Array)
        {
            Length++;
        }
        char[] String_Reverse = null;
        for (int i = Length - 1, j = 0; Length >= 0; Length--, j++)
        {
            //Here is the error I am facing, Null Reference Exception

            String_Reverse[j] = String_Array[i];
        }
        string Reverse = new string(String_Reverse);

        Console.WriteLine("Length of the String " + InputString + " is :" + Length + " and Reverse of the String is :" + Reverse);
        Console.ReadLine();

also the char array or even string has Length property. no need to use foreach and count. — M.kazem Akhgary, Feb 01 '16 at 13:15
thats alright, But i just want to know what is wrong in this code. — Moranis, Feb 01 '16 at 13:17
you set null to String_Reverse. you need to create new array. `char[] String_Reverse = new char[Length]` — M.kazem Akhgary, Feb 01 '16 at 13:18
"//Here is the error I am facing" -- You must **always** post **which error** you're facing. Not just "here it happens". **What** happened? — Lasse V. Karlsen, Feb 01 '16 at 13:18

score 1 · Answer 1 · answered Feb 01 '16 at 13:16

1

You never actually initialize String_Reverse as an array

Also, instead of using a foreach loop to get the length of an array you can use String_Array.Length this will return the length of the array without having to loop over each item in the array.

answered Feb 01 '16 at 13:16

Gilgamesh

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What is wrong with this following c# code just trying to find out Length and reverse of a given String

1 Answers1