title: Automatically check a CheckBox if file exists
body: <p>I want to create a program such that if the file exists, the checkbox will auto check. </p>
  
  <pre><code>private void button3_Click(object sender, EventArgs e)
  {
    //check whether the file is exist or not
    if (string curFile = @"C:\s\test.txt")
    {
  
    }
    else
    {
  
    }
  }
  </code></pre>