DataGridViewCellStyle.Format, propriété

// Configures the appearance and behavior of a DataGridView control.
private void InitializeDataGridView()
{
    // Initialize basic DataGridView properties.
    dataGridView1.Dock = DockStyle.Fill;
    dataGridView1.BackgroundColor = Color.LightGray;
    dataGridView1.BorderStyle = BorderStyle.Fixed3D;

    // Set property values appropriate for read-only display and 
    // limited interactivity. 
    dataGridView1.AllowUserToAddRows = false;
    dataGridView1.AllowUserToDeleteRows = false;
    dataGridView1.AllowUserToOrderColumns = true;
    dataGridView1.ReadOnly = true;
    dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect;
    dataGridView1.MultiSelect = false;
    dataGridView1.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.None;
    dataGridView1.AllowUserToResizeColumns = false;
    dataGridView1.ColumnHeadersHeightSizeMode = 
        DataGridViewColumnHeadersHeightSizeMode.DisableResizing;
    dataGridView1.AllowUserToResizeRows = false;
    dataGridView1.RowHeadersWidthSizeMode = 
        DataGridViewRowHeadersWidthSizeMode.DisableResizing;

    // Set the selection background color for all the cells.
    dataGridView1.DefaultCellStyle.SelectionBackColor = Color.White;
    dataGridView1.DefaultCellStyle.SelectionForeColor = Color.Black;

    // Set RowHeadersDefaultCellStyle.SelectionBackColor so that its default
    // value won't override DataGridView.DefaultCellStyle.SelectionBackColor.
    dataGridView1.RowHeadersDefaultCellStyle.SelectionBackColor = Color.Empty;

    // Set the background color for all rows and for alternating rows. 
    // The value for alternating rows overrides the value for all rows. 
    dataGridView1.RowsDefaultCellStyle.BackColor = Color.LightGray;
    dataGridView1.AlternatingRowsDefaultCellStyle.BackColor = Color.DarkGray;

    // Set the row and column header styles.
    dataGridView1.ColumnHeadersDefaultCellStyle.ForeColor = Color.White;
    dataGridView1.ColumnHeadersDefaultCellStyle.BackColor = Color.Black;
    dataGridView1.RowHeadersDefaultCellStyle.BackColor = Color.Black;

    // Set the Format property on the "Last Prepared" column to cause
    // the DateTime to be formatted as "Month, Year".
    dataGridView1.Columns["Last Prepared"].DefaultCellStyle.Format = "y";

    // Specify a larger font for the "Ratings" column. 
    using (Font font = new Font(
        dataGridView1.DefaultCellStyle.Font.FontFamily, 25, FontStyle.Bold))
    {
        dataGridView1.Columns["Rating"].DefaultCellStyle.Font = font;
    }

    // Attach a handler to the CellFormatting event.
    dataGridView1.CellFormatting += new
        DataGridViewCellFormattingEventHandler(dataGridView1_CellFormatting);
}