Currently I am sending one Array List from form2 to form 1 and it works fine.

```
Form1 form2 = new Form1(this, SampleArrayList); //pass form reference and an arraylist
form2.Show();
this.Hide();

```

And on form1 I associate SampleArrayList with local Array List.

```
Form2 formParent;
ArrayList SampleArrayList;
public MainForm(Form2 par, ArrayList _SampleArrayList)
{            
       InitializeComponent();
       this.formParent = par;
       this.SampleArrayList = _SampleArrayList;
}

```

However I want to avoid creating new instance of Form1 

```
form2 = new Form1(this, SampleArrayList);

```

I want to send Array List to currently running instance of Form1. What would be best way to do this. Thank you