title: Changing text box from another class
body: <p>I'm trying to change value of a text box located in</p>
  
  <pre><code>public partial class Form1 : Form
  </code></pre>
  
  <p>from another class. I've tried something like this</p>
  
  <pre><code>public void echo(string text)
  {
      this.textBox1.AppendText(text + Environment.NewLine);
  }
  </code></pre>
  
  <p>From another class I'm calling it like</p>
  
  <pre><code>Form1 cout = new Form1();
  cout.echo("Does this work?");
  </code></pre>
  
  <p>And I get blank output. I also tried to add the <code>static</code> keyword to the <code>echo</code> method, but I got the same result. I searched over Stack&nbsp;Overflow and didn't get any solution to work. And one thing that triggers me, if I add <code>cout.Show()</code> the same form pop out with valid <code>textBox1</code> content. Why is that?</p>
  
  <p>Why it is not showing content right away? And how do I fix this?</p>