title: Change label from 2 different Forms
body: <p>I'm trying to change labels when pressing on a button on 2 different windowsForms.</p>
  
  <p>If I open the second form I can change it easy but I cant figure out how to change data on a Form that's already open. I keep getting <code>NullRefferenceExecption</code>.</p>
  
  <p>This is the code i use in my buttons on <code>Form1</code> and <code>Form2</code>:</p>
  
  <pre><code>public Form2 m_Form2;
  
  m_Form2 = new Form2();
  m_Form2.Show();
  m_Form2.label1.Text = "pressed on form 1";
  </code></pre>
  
  <p>And:</p>
  
  <pre><code>public Form1 m_Form1;
  
  m_Form1.label1.Text = "pressed on form 2";
  </code></pre>