error: Use of unassigned local variable
<p>I have this method:</p>

<pre><code>public static void Add(int _Serial, string _Name, long? _number1, long? _number2)
{
    // ...
}
</code></pre>

<p>and use this code for send date to method:</p>

<pre><code>long? _num1;
long? _num2;
if (txtNumber1.Text != null &amp;&amp; txtNumber1.Text != "")
{
    _num1= long.Parse(txtNumber1.Text);
}
if (txtNumber2.Text != null &amp;&amp; txtNumber2.Text != "")
{
    _num2= long.Parse(txtNumber2.Text);
}
Add(22, "Kati", _num1, _num2)
</code></pre>

<p>but Error <code>_num1</code> &amp; <code>_num2</code> in <code>Add(...)</code>.</p>

<p>Error:</p>

<blockquote>
  <p>Use of unassigned local variable '_num1'</p>
  
  <p>Use of unassigned local variable '_num2'</p>
</blockquote>
