How to Export a Gridview.Datasource to a Datatable or Dataset

How can I export a GridView.DataSource to a datatable or dataset?

You should convert first DataSource in BindingSource, look example

BindingSource bs = (BindingSource)dgrid.DataSource; // Se convierte el DataSource 
DataTable tCxC = (DataTable) bs.DataSource;

With the data of tCxC you can do anything.

Exporting a grid view to datatable

The Following Code will help you in adding the Gridview rows to DataTable

 DataTable dt = new DataTable();    
    for (int j = 0; j < grdList.Rows.Count; j++)
    {
        DataRow dr;
        GridViewRow row = grdList.Rows[j];
        dr = dt.NewRow();
        for (int i = 0; i < row.Cells.Count; i++)
        {
            dr[i] = row.Cells[i].Text;
        }

        dt.Rows.Add(dr);
    }

How to build a DataTable from a DataGridView?

Well, you can do

DataTable data = (DataTable)(dgvMyMembers.DataSource);

and then use

data.Columns.Remove(...);

I think it's the fastest way. This will modify data source table, if you don't want it, then copy of table is reqired. Also be aware that DataGridView.DataSource is not necessarily of DataTable type.

Putting GridView data in a DataTable

you can do something like this:

DataTable dt = new DataTable();
for (int i = 0; i < GridView1.Columns.Count; i++)
    {
        dt.Columns.Add("column"+i.ToString());
    }
foreach (GridViewRow row in GridView1.Rows)
    {
        DataRow dr = dt.NewRow();
        for(int j = 0;j<GridView1.Columns.Count;j++)
            {
                dr["column" + j.ToString()] = row.Cells[j].Text;
            }

            dt.Rows.Add(dr);
    }

And that will show that it works.

GridView6.DataSource = dt;
GridView6.DataBind();

Filling DataTable from GridView in C#

 I solved like this
           if (myGridView.Rows.Count > 0)
            {
                var dt = new DataTable();
                dt.Columns.Add("Column1", typeof(string));
                dt.Columns.Add("Column2", typeof(Int64));
                dt.Columns.Add("Column3", typeof(string));

                foreach (GridViewRow row in gd_endYearSchool.Rows)
                {
                    var id = row.Cells[1].Text;
         //for find textbox
          var tb1 = row.Cells[2].FindControl("tbNr") as TextBox;
                    int nrord = 0;
                    if (tb1 != null)
                    {
                        var ord = tb1.Text;
                        if (!Int64.TryParse(ord, out nrord))
                        {
                            nrord = 0;
                        }
                    }
                    var text=row.Cell[3].text;
                    dt.Rows.Add(id,nrord,text);
                }

            }

how can I set a dataset or datatable row to a value taken from a gridview textbox entry?

Use this code. May be this is what you need.

 string txtName = ((TextBox) GridView4.Rows[RowIndex].FindControl("textBox1")).Text; string txtEmail = ((TextBox) GridView4.Rows[RowIndex].FindControl("textBox2")).Text; string txtMobile = ((TextBox) GridView4.Rows[RowIndex].FindControl("textBox3")).Text;
 if (txtName != null) {   EditT.Tables[0].Rows[RowIndex]["Name"] = txtName; }

 if (txtEmail != null) {   EditT.Tables[0].Rows[RowIndex]["Email"] = txtEmail; }
 if (txtMobile != null) {   EditT.Tables[0].Rows[RowIndex]["Mobile"] = txtMobile; }

How to make a DataTable from DataGridView without any Datasource?

Might be a nicer way to do it but otherwise it would be fairly trivial to just loop through the DGV and create the DataTable manually.

Something like this might work:

DataTable dt = new DataTable();
foreach(DataGridViewColumn col in dgv.Columns)
{
   dt.Columns.Add(col.Name);    
}

foreach(DataGridViewRow row in dgv.Rows)
{
    DataRow dRow = dt.NewRow();
    foreach(DataGridViewCell cell in row.Cells)
    {
        dRow[cell.ColumnIndex] = cell.Value;
    }
    dt.Rows.Add(dRow);
}