Below example showing you how to add the row number in WebGrid.
You just need add the following script inside the grid columns.
grid.Column(header: "No.",
format: item => item.WebGrid.Rows.IndexOf(item) + 1 + Math.Round(Convert.ToDouble(grid.TotalRowCount / grid.PageCount) / grid.RowsPerPage) * grid.RowsPerPage * grid.PageIndex)
The completed WebGrip example as below:
@{
var grid = new WebGrid(@Model,
@grid.GetHtml(
columns: new [] {
grid.Column(header: "No.",
format: item => item.WebGrid.Rows.IndexOf(item) + 1 + Math.Round(Convert.ToDouble(grid.TotalRowCount / grid.PageCount) / grid.RowsPerPage) * grid.RowsPerPage * grid.PageIndex),
grid.Column("Title"),
grid.Column("Date")
}
}