Find vowels character in a String

Introduction

Some one ask a question to me, how to find all vowels from a string without repeating vowels ( means you can find out vowels from a string but if one is come out like 'E' from that string, then next time it is not included with the output.

Now I write a code for Find out vowels from a given string.

Example

using System;

class Program

{

    static void Main()

    {

        string value1 = RemoveDuplicateChars("AERTJEIUO");

        for (int i = 0; i <= value1.Length - 1; i++)

        {

                // code that checks the char is vowel or not

            if (65 == (int)value1[i] || 69 == (int)value1[i] || 73 == (int)value1[i] || 79 == (int)value1[i] || 85 == (int)value1[i]) 

            {

                Console.WriteLine(value1[i]);

            }

        }

        Console.ReadKey();

    }

 

    // method for removing the duplicate characters

        static string RemoveDuplicateChars(string key)

    {

        string val1 = "";

        string result = "";

        foreach (char value in key)

        {

            if (val1.IndexOf(value) == -1)

            {

                val1 += value;

                result += value;

            }

        }

        return result;

    }

}

Output