Unable to pass data between forms to a listView

[tet3828]

I have a two forms that I created using the design view of Visual C# Express (Form1 & infoEntry). I set the properties to of the listview in Form1.

public System.Windows.Forms.ListView toSend;

I've invoked the second form and sent some data using code below. Works great.

infoEntry dataWindow = new infoEntry(); 
dataWindow.filePath(selectedFile); \\sending some data to new form
dataWindow.ShowDialog();

I'm running into a problem when I attempt to send data back to Form1. The following code is within a button_Click

            string patientid = (patientidSender.ToString());
            string shift2 = (shift2Sender.ToString());
            string[] row1 = { ("value1"), ("value2") };
            Form1.toSend.Items.Add("test").SubItems.AddRange(row1); \\<--- this line causing the error.

The last line of code causes an error "An object reference is required for the non-static field"
But when I use that exact same line in the First Form (Form1) it doesn't seem to have a problem addind items. What can I do to fix this please? And thank you in advance.

[Rogachev]

In my opinion:
If you must to create the instance of your toSend variable before you try to add items. In your code example you try to add items to the null object.

[tet3828]

The object toSend is a listView box in Form1. I'm attempting to populate it with varaibles from a text box in another form that was invoked by Form1. So if I'm understanding the response correctly-- I need to make a variable that sends variables? I new to coding and if that is the case I can't even begin to visualize how to do so.

[TnTinMN]

Add a property to "infoEntry" to accept a reference to the ListView.

    private ListView _lv;
    public ListView lv
    {
        get { return _lv; }
        set { _lv = value; }
    }

Then set that property before showing "dataWindow"

dataWindow.lv = this.toSend;
dataWindow.ShowDialog();

Then: lv.Items.Add("test").SubItems.AddRange(row1);