公开dataGridView1

Question

Im trying to make my dataGridView public so I can access it from another class. I attempted to do so by doing this

public DataGridView dgv = new DataGridView();

To test this change out, I tried populating it on Form1 with information using

dgv.DataSource = prevEx.ToList();

It would previously get filled with information but now it doesnt get populated at all, and I'm left staring at an empty DGV . I know for a fact prevEx has data in it because prior to making it public, the DGV would get populated.

I know I'm initializing the new DGV prior to the step in which it is supposed to populate the field (its up top with all my other public variables), so thats not the problem so as of now I'm at a loss. Any help would be awesome.

To clear up some confusion here is more code.

public partial class Form1 : Form
    {
    public static Microsoft.Office.Interop.Excel._Application excelApp = new Microsoft.Office.Interop.Excel.Application() { DisplayAlerts = false, Visible = false };
    System.Diagnostics.Process proc = System.Diagnostics.Process.GetCurrentProcess();

    public List<Attorney> listOfAttys = Helpers.getAttorneys();
    public static DataGridView dgv = new DataGridView();

    public static string fileName = null;
    public static string chatterCase = null;
    public static string userName = null;
    public static string attorneyNum = null;
    public static int batchID;
    public static string ID;
    public static DateTime dateHold;
    public static string holdDesc = null;
    public static int startingRow;
    public static string holdAccount = null;

---

    public void btnLoad_Click(object sender, EventArgs e)
    {
        txtbxFilename.Text = null;
        txtbxChatterCase.Text = null;
        txtbxUserName.Text = null;
        txtbxRowNum.Text = null;

        System.IO.Stream myStream = null;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();

        openFileDialog1.InitialDirectory = "C:\\";
        openFileDialog1.Filter = "Excel files |*.xls;*.xlsx";
        openFileDialog1.FilterIndex = 2;
        openFileDialog1.RestoreDirectory = true;

        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            try
            {
                if ((myStream = openFileDialog1.OpenFile()) != null)
                {
                    fileName = txtbxFilename.Text = openFileDialog1.FileName;

                    myStream.Close();
                    myStream.Dispose();
                }
            }
            catch (Exception ex)
            {
                excelApp.Quit();
                MessageBox.Show("Error: Could not read file from disk. Original error: " + ex.Message);
            }
        }

        var prevEx = LegalTransactionList.previewExcel();
        dgv.DataSource = prevEx.ToList();

    }

Answer 1

Declare with a static tag too:

public static DataGridView dgv = new DataGridView();

This will make it retain data between classes (globally).

In your other class call it ass such:

MyClassName.dgv.DataSource = prevEx.ToList();

Answer 2

Make it with a static tag:

  public static DataGridView dgv = new DataGridView();

Assuming this control belongs to Class Foo, to access it another class simply use

  Foo.dgv.DataSource = prevEx.ToList();

If class Foo has been instantiated in the class that needs to call it ie

   Foo bar = new Foo();

Then you would not need the static tag and it would be accessed as such:

bar.dgv.DataSource = prevEx.ToList();

However my recomendation would be to make a public static list, and set the data source inside the same class as dgv, instead of making the dgv public and static.

And one last suggestion, try setting the dataSource to null first.

  dgv.DataSource = null;
  dgv.DataSource = prevEx.ToList();