C# Display repeated letter in string
<p>I'm trying to figure out how to display the repeated letter in a string. For example if the entered string was "red house" it would show that the letter "e" was repeated, then it would be displayed in the label I created. This is a basic program, Here is what I've written thus far. Any help is appreciated.</p>

<pre><code>private void button1_Click(object sender, EventArgs e)
    {
        string enteredWord = textBox1.Text;
        char letter;


        for (int index = 0; index &lt; enteredWord.Length; index++) 
        {
            letter = enteredWord[index];

            if (letter == enteredWord[index])
            {
                label1.Text = (letter.ToString());
            }
            else
            { return; 

            }
</code></pre>
