create custom gridview template fields for a List<> - asp.net

Question

I have a List of Lists of string . I want to show it to user using a gridview . as number of columns are not known I decided to create gridview fields dynamically . I found some tutorials but all of them use DataTable . I tried to use the same but I have problem with databinding event's "_columnName" :
void field_DataBinding(object sender, EventArgs e)
{
TextBox txtdata = (TextBox)sender;
GridViewRow container = (GridViewRow)txtdata.NamingContainer;
object dataValue = DataBinder.Eval(container.DataItem, _columnName);
if (dataValue != DBNull.Value)
{
txtdata.Text = dataValue.ToString();
}
}
as there is no column in list . any suggestion is appreciated .

Answer 1

A much easier way would be to set AutoGenerateColumns to true and use a DataTable as DataSource.
For example ( the aspx can be an empty GridView ):
List<List<String>> data = new List<List<String>>() {
new List<String>(){"Row1_Col1", "Row1_Col2", "Row1_Col3"},
new List<String>(){"Row2_Col1", "Row2_Col2", "Row2_Col3"},
new List<String>(){"Row3_Col1", "Row3_Col2", "Row3_Col3"},
new List<String>(){"Row4_Col1", "Row4_Col2", "Row4_Col3"},
new List<String>(){"Row5_Col1", "Row5_Col2", "Row5_Col3"},
};
var tbl = new DataTable();
int maxFieldCount = data.Max(l => l.Count);
for (int i = 1; i <= maxFieldCount; i++)
tbl.Columns.Add("Column" + i);
foreach (var list in data)
{
DataRow newRow = tbl.Rows.Add();
newRow.ItemArray = list.ToArray();
}
now it can be used as DataSource of the GridView:
GridView1.DataSource = tbl;
GridView1.DataBind();