C# arguments values in methods
<p>If I write <code>a = a +115</code> my <code>MessageBox</code> will return 215 but if write like <code>a=115;</code> it will display 115.</p>

<p>Why is that?</p>

<pre><code>private void button1_Click(object sender, EventArgs e)
{
    int c=100;
    MessageBox.Show(Count(c).ToString());
}

public int Count(int a)
{
    a=115;
    return a;
}
</code></pre>
