protected void btnAddComments_Click(object sender, EventArgs e)
{
// ExStart:AddComments
// Accessing the reference of the worksheet that is currently active and add a dummy value to cell A1
GridWorksheet sheet = GridWeb1.WorkSheets[GridWeb1.ActiveSheetIndex];
sheet.Cells["A1"].PutValue("This cell has a comment added, hover to view.");
// Resize first column
sheet.Cells.SetColumnWidth(0, 140);
// Adding comment to "A1" cell of the worksheet
GridComment comment = sheet.Comments[sheet.Comments.Add("A1")];
// Setting the comment note
comment.Note = "These are my comments for the cell";
// ExEnd:AddComments
}