Question

I have a Form1 and I do some processing in the other class.
What would be the proper way to output information to Form1 textBox9 ?

This is how I do it, but it only work partially, only when the form is active.

This is what I have in my class:

var form = Form.ActiveForm as Form1;
if (form != null)
{
 form.updateLabel("DBadd[" + counter + "]" + NAME2);
}

This is that I have in my Form1:

    delegate void updateStatus(String value);
    public void updateLabel(String value)
    {
        if (textBox9.InvokeRequired)
        {
            updateStatus del = new updateStatus(updateCodemicroLabel);
            textBox9.Invoke(del, new object[] { value });
        }
        else
        {
            {
                textBox9.Text = value;
            }
        }
    }

This is how my class called:

    private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
    {
        new className().runTask();
    }

Answer 1

Instead of using Form.ActiveForm you need to pass the instance to the class so it can call whatever.updateLabel() with whatever being the instance.