Upload Textfile to Data Table

Question

I'm trying to allow the user to upload existing information to a data table. Here's what the code is for the upload:

private void label30_Click(object sender, EventArgs e)
        {
            OpenFileDialog ofd = new OpenFileDialog();
            if (ofd.ShowDialog() == DialogResult.OK)
            {
                StreamReader read = new StreamReader(File.OpenRead(ofd.FileName));
                string[] lines = File.ReadAllLines(ofd.FileName);
                string[] values;

                for (int i = 31; i < lines.Length; i++)
                {
                    values = lines[i].ToString().Split(',');
                    string[] row = new string[values.Length];

                    for (int j = 0; j < values.Length; j++)
                    {
                        row[j] = values[j].Trim();
                    }
                    stkSheetdgv.Rows.Add(row);
                    read.Close();
                    read.Dispose();
                }
                
            }
        }

There is a lot of other information inside the text file, hence the reason int i = 31. I'm getting System.InvalidOperationException: 'Rows cannot be programmatically added to the DataGridView's rows collection when the control is data-bound.'

Can someone tell me what is missing to make this work? I can add more code for the dt if necessary. Let me know.

            stkSheetdgv.AutoGenerateColumns = false;
            DataTable dt = new DataTable();
            dt.Columns.Add("Wire", typeof(String));
            dt.Columns.Add("Pole", typeof(String));
            dt.Columns.Add("Primary Unit", typeof(String));
            dt.Columns.Add("Down Guy", typeof(String));
            dt.Columns.Add("Anchor", typeof(String));
            dt.Columns.Add("Transformer", typeof(String));
            dt.Columns.Add("Ground", typeof(String));
            dt.Columns.Add("Riser/Disconnect", typeof(String));
            dt.Columns.Add("Misc.", typeof(String));
            DataGridViewComboBoxColumn wire = new DataGridViewComboBoxColumn();
            var wirelist = new List<string>() {"AAC 1/0 POPPY", "AAC 477 COSMOS"};
            wire.DataSource = wirelist;
            wire.HeaderText = "Wire";
            wire.DataPropertyName = "Wire";
            DataGridViewComboBoxColumn pole = new DataGridViewComboBoxColumn();
            var polelist = new List<string>() {"30C4 CCA", "30C5 CCA"};
            pole.DataSource = polelist;
            pole.HeaderText = "Pole";
            pole.DataPropertyName = "Pole";
            DataGridViewComboBoxColumn primary = new DataGridViewComboBoxColumn();
            var primarylist = new List<string>() {"C1-LD", "C2-LD"};
            primary.DataSource = primarylist;
            primary.HeaderText = "Primary Unit";
            primary.DataPropertyName = "Primary Unit";
            DataGridViewComboBoxColumn down = new DataGridViewComboBoxColumn();
            var downlist = new List<string>() {"E1-5-144", "E1-5-144P"};
            down.DataSource = downlist;
            down.HeaderText = "Down Guy";
            down.DataPropertyName = "Down Guy";
            DataGridViewComboBoxColumn anch = new DataGridViewComboBoxColumn();
            var anchlist = new List<string>() {"F1-2 Expansion", "F1-2 Plate"};
            anch.DataSource = anchlist;
            anch.HeaderText = "Anchor";
            anch.DataPropertyName = "Anchor";
            DataGridViewComboBoxColumn trans = new DataGridViewComboBoxColumn();
            var translist = new List<string>() { "G311-15kVA", "G311-25kVA"};
            trans.DataSource = translist;
            trans.HeaderText = "Transformer";
            trans.DataPropertyName = "Transformer";
            DataGridViewComboBoxColumn ground = new DataGridViewComboBoxColumn();
            var groundlist = new List<string>() { "M2-12", "M2-11" };
            ground.DataSource = groundlist;
            ground.HeaderText = "Ground";
            ground.DataPropertyName = "Ground";
            DataGridViewComboBoxColumn rise = new DataGridViewComboBoxColumn();
            var riserlist = new List<string>() { "M8-60-10'", "M8-100-10'"};
            rise.DataSource = riserlist;
            rise.HeaderText = "Riser/Disconnect";
            rise.DataPropertyName = "Riser/Disconnect";
            DataGridViewComboBoxColumn misc = new DataGridViewComboBoxColumn();
            var misclist = new List<string>() { "M5-5LD", "M5-5HD"};
            misc.DataSource = misclist;
            misc.HeaderText = "Misc.";
            misc.DataPropertyName = "Misc.";
            stkSheetdgv.DataSource = dt;
            stkSheetdgv.Columns.AddRange(wire, pole, primary, down, anch, trans, ground, rise, misc);
            stkSheetdgv.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells;

You will need to add a [NewRow](https://learn.microsoft.com/en-us/dotnet/api/system.data.datatable.newrow?view=netcore-3.1) first, assign values to that new row, then add to the `DataTable`. — Hayden, Aug 14 '20 at 00:20
Have a look further at [this question](https://stackoverflow.com/questions/8708057/rows-cannot-be-programmatically-added-to-the-datagridviews-row-collection-when). — Hayden, Aug 14 '20 at 00:27
Are you able to provide how you initialise stkSheetdgv (with columns and all) and the format of your csv. — Hayden, Sep 01 '20 at 03:08
When providing the information, edit the question then tag me. — Hayden, Sep 01 '20 at 03:11

Hayden · Accepted Answer · 2020-09-01T04:08:59.953

There are two different ways to resolve this issue, either by removing the assignment of the DataSource (e.g. remove stkSheetdgv.DataSource = dt;) on the DataGridView, or adding to the DataSource explicitly:

Code

private void label30_Click(object sender, EventArgs e)
{
    DataTable dataTable = (DataTable)stkSheetdgv.DataSource;
    OpenFileDialog ofd = new OpenFileDialog();
    if (ofd.ShowDialog() == DialogResult.OK)
    {
        using (StreamReader read = new StreamReader(File.OpenRead(ofd.FileName)))
        {
            string[] lines = File.ReadAllLines(ofd.FileName);
            string[] values;

            for (int i = 31; i < lines.Length; i++)
            {
                values = lines[i].ToString().Split(',');
                var dataRow = dataTable.NewRow();
                for (int j = 0; j < values.Length; j++)
                {
                    dataRow[j] = values[j].Trim();
                }
                dataTable.Rows.Add(dataRow);
                dataTable.AcceptChanges();
            }
        }
    }
}

Edit

The reason that you're receiving the error is due to the csv having more columns than specified on the DataTable. The CSV file that I used was:

AAC 1/0 POPPY,30C4 CCA,C1-LD,E1-5-144,F1-2 Expansion,G311-15kVA,M2-12,M8-60-10',M5-5LD
AAC 477 COSMOS,30C5 CCA,C2-LD,E1-5-144P,F1-2 Plate,G311-25kVA,M2-11,M8-100-10',M5-5HD

Which worked perfectly fine for me.

it's having an error now at `dataRow[j] = values[j].Trim();` and the error reads `System.IndexOutOfRangeException: 'Cannot find column 9.'` — Worm, Sep 01 '20 at 04:02

Upload Textfile to Data Table

1 Answers1