DataGridView.ReadOnly Property

Definition

Namespace:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Source:

DataGridView.cs

Gets or sets a value indicating whether the user can edit the cells of the DataGridView control.

public:
 property bool ReadOnly { bool get(); void set(bool value); };

[System.ComponentModel.Browsable(true)]
public bool ReadOnly { get; set; }

[<System.ComponentModel.Browsable(true)>]
member this.ReadOnly : bool with get, set

Public Property ReadOnly As Boolean

Property Value

Boolean

true if the user cannot edit the cells of the DataGridView control; otherwise, false. The default is false.

Attributes

BrowsableAttribute

Exceptions

InvalidOperationException

The specified value when setting this property is true, the current cell is in edit mode, and the current cell contains changes that cannot be committed.

Exception

The specified value when setting this property would cause the control to enter edit mode, but initialization of the editing cell value failed and either there is no handler for the DataError event or the handler has set the ThrowException property to true. The exception object can typically be cast to type FormatException.

Examples

The following code example illustrates the use of this property in a DataGridView control intended primarily for display. In this example, the visual appearance of the control is customized in several ways and the control is configured for limited interactivity. This example is part of a larger example available in the DataGridViewCellStyle class overview.

// 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);
}

' Configures the appearance and behavior of a DataGridView control.
Private Sub 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. 
    Dim font As New Font( _
        dataGridView1.DefaultCellStyle.Font.FontFamily, 25, FontStyle.Bold)
    Try
        dataGridView1.Columns("Rating").DefaultCellStyle.Font = font
    Finally
        font.Dispose()
    End Try

End Sub

Remarks

A cell is read-only if the value of the ReadOnly property is true for the cell, the cell's row, the cell's column, or the DataGridView.

See also

• DataGridView Control (Windows Forms)