DataGridView.ColumnCount Property

Definition

Namespace:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Gets or sets the number of columns displayed in the DataGridView.

public:
 property int ColumnCount { int get(); void set(int value); };

[System.ComponentModel.Browsable(false)]
public int ColumnCount { get; set; }

[<System.ComponentModel.Browsable(false)>]
member this.ColumnCount : int with get, set

Public Property ColumnCount As Integer

Property Value

Int32

The number of columns displayed in the DataGridView.

Attributes

BrowsableAttribute

Exceptions

ArgumentOutOfRangeException

The specified value when setting this property is less than 0.

InvalidOperationException

When setting this property, the DataSource property has been set.

Examples

The following code example demonstrates how to set the ColumnHeadersDefaultCellStyle, AutoSizeRowsMode, ColumnHeadersBorderStyle, CellBorderStyle, GridColor, BackgroundColor, RowHeadersVisible, SelectionMode, ColumnCount, and MultiSelect properties. In addition, the code example demonstrates how to set the DataGridViewColumn.Name and DataGridViewColumn.DefaultCellStyle properties. To run this example, paste the code into a form that contains a DataGridView named dataGridView1, and then call the SetUpDataGridView method from the form's constructor or Load event handler. Ensure all events are associated with their event handlers.

void SetUpDataGridView()
{
   this->Controls->Add( dataGridView1 );
   dataGridView1->ColumnCount = 5;
   DataGridViewCellStyle^ style = dataGridView1->ColumnHeadersDefaultCellStyle;
   style->BackColor = Color::Navy;
   style->ForeColor = Color::White;
   style->Font = gcnew System::Drawing::Font( dataGridView1->Font,FontStyle::Bold );
   dataGridView1->EditMode = DataGridViewEditMode::EditOnEnter;
   dataGridView1->Name = "dataGridView1";
   dataGridView1->Location = Point(8,8);
   dataGridView1->Size = System::Drawing::Size( 500, 300 );
   dataGridView1->AutoSizeRowsMode = DataGridViewAutoSizeRowsMode::DisplayedCellsExceptHeaders;
   dataGridView1->ColumnHeadersBorderStyle = DataGridViewHeaderBorderStyle::Raised;
   dataGridView1->CellBorderStyle = DataGridViewCellBorderStyle::Single;
   dataGridView1->GridColor = SystemColors::ActiveBorder;
   dataGridView1->RowHeadersVisible = false;
   dataGridView1->Columns[ 0 ]->Name = "Release Date";
   dataGridView1->Columns[ 1 ]->Name = "Track";
   dataGridView1->Columns[ 1 ]->DefaultCellStyle->Alignment = DataGridViewContentAlignment::MiddleCenter;
   dataGridView1->Columns[ 2 ]->Name = "Title";
   dataGridView1->Columns[ 3 ]->Name = "Artist";
   dataGridView1->Columns[ 4 ]->Name = "Album";

   // Make the font italic for row four.
   dataGridView1->Columns[ 4 ]->DefaultCellStyle->Font = gcnew System::Drawing::Font( DataGridView::DefaultFont,FontStyle::Italic );
   dataGridView1->SelectionMode = DataGridViewSelectionMode::FullRowSelect;
   dataGridView1->MultiSelect = false;
   dataGridView1->BackgroundColor = Color::Honeydew;
   dataGridView1->Dock = DockStyle::Fill;
   dataGridView1->CellFormatting += gcnew DataGridViewCellFormattingEventHandler( this, &Form1::dataGridView1_CellFormatting );
   dataGridView1->CellParsing += gcnew DataGridViewCellParsingEventHandler( this, &Form1::dataGridView1_CellParsing );
   addNewRowButton->Click += gcnew EventHandler( this, &Form1::addNewRowButton_Click );
   deleteRowButton->Click += gcnew EventHandler( this, &Form1::deleteRowButton_Click );
   ledgerStyleButton->Click += gcnew EventHandler( this, &Form1::ledgerStyleButton_Click );
   dataGridView1->CellValidating += gcnew DataGridViewCellValidatingEventHandler( this, &Form1::dataGridView1_CellValidating );
}

private void SetUpDataGridView()
{
    this.Controls.Add(dataGridView1);
    dataGridView1.ColumnCount = 5;
    DataGridViewCellStyle style = 
        dataGridView1.ColumnHeadersDefaultCellStyle;
    style.BackColor = Color.Navy;
    style.ForeColor = Color.White;
    style.Font = new Font(dataGridView1.Font, FontStyle.Bold);

    dataGridView1.EditMode = DataGridViewEditMode.EditOnEnter;
    dataGridView1.Name = "dataGridView1";
    dataGridView1.Location = new Point(8, 8);
    dataGridView1.Size = new Size(500, 300);
    dataGridView1.AutoSizeRowsMode = 
        DataGridViewAutoSizeRowsMode.DisplayedCellsExceptHeaders;
    dataGridView1.ColumnHeadersBorderStyle = 
        DataGridViewHeaderBorderStyle.Raised;
    dataGridView1.CellBorderStyle = DataGridViewCellBorderStyle.Single;
    dataGridView1.GridColor = SystemColors.ActiveBorder;
    dataGridView1.RowHeadersVisible = false;

    dataGridView1.Columns[0].Name = "Release Date";
    dataGridView1.Columns[1].Name = "Track";
    dataGridView1.Columns[1].DefaultCellStyle.Alignment = 
        DataGridViewContentAlignment.MiddleCenter;
    dataGridView1.Columns[2].Name = "Title";
    dataGridView1.Columns[3].Name = "Artist";
    dataGridView1.Columns[4].Name = "Album";

    // Make the font italic for row four.
    dataGridView1.Columns[4].DefaultCellStyle.Font = new Font(DataGridView.DefaultFont, FontStyle.Italic);

    dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect;
    dataGridView1.MultiSelect = false;

    dataGridView1.BackgroundColor = Color.Honeydew;

    dataGridView1.Dock = DockStyle.Fill;

    dataGridView1.CellFormatting += new DataGridViewCellFormattingEventHandler(dataGridView1_CellFormatting);
    dataGridView1.CellParsing += new DataGridViewCellParsingEventHandler(dataGridView1_CellParsing);
    addNewRowButton.Click += new EventHandler(addNewRowButton_Click);
    deleteRowButton.Click += new EventHandler(deleteRowButton_Click);
    ledgerStyleButton.Click += new EventHandler(ledgerStyleButton_Click);
    dataGridView1.CellValidating += new DataGridViewCellValidatingEventHandler(dataGridView1_CellValidating);
}

Private Sub SetUpDataGridView()

    Me.Controls.Add(dataGridView1)
    dataGridView1.ColumnCount = 5

    With dataGridView1.ColumnHeadersDefaultCellStyle
        .BackColor = Color.Navy
        .ForeColor = Color.White
        .Font = New Font(dataGridView1.Font, FontStyle.Bold)
    End With

    With dataGridView1
        .EditMode = DataGridViewEditMode.EditOnEnter
        .Name = "dataGridView1"
        .Location = New Point(8, 8)
        .Size = New Size(500, 300)
        .AutoSizeRowsMode = _
            DataGridViewAutoSizeRowsMode.DisplayedCellsExceptHeaders
        .ColumnHeadersBorderStyle = _
            DataGridViewHeaderBorderStyle.Raised
        .CellBorderStyle = _
            DataGridViewCellBorderStyle.Single
        .GridColor = SystemColors.ActiveBorder
        .RowHeadersVisible = False

        .Columns(0).Name = "Release Date"
        .Columns(1).Name = "Track"
        .Columns(1).DefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter
        .Columns(2).Name = "Title"
        .Columns(3).Name = "Artist"
        .Columns(4).Name = "Album"

        ' Make the font italic for row four.
        .Columns(4).DefaultCellStyle.Font = _
            New Font(Control.DefaultFont, _
                FontStyle.Italic)

        .SelectionMode = _
            DataGridViewSelectionMode.FullRowSelect
        .MultiSelect = False

        .BackgroundColor = Color.Honeydew

        .Dock = DockStyle.Fill
    End With

End Sub

Remarks

Setting the ColumnCount property to 0 will remove all columns from the DataGridView.

If ColumnCount is reset to a value less than the current value, columns will be removed from the end of the Columns collection. If ColumnCount is set to a value greater than the current value, columns will be added to the end of the Columns collection.

This property can be used with the RowCount property to create a simple DataGridView for displaying and editing text.

For more information about how to handle events, see Handling and Raising Events.

See also

• DataGridView Control (Windows Forms)