Questa documentazione è stata archiviata e non viene gestita.

Classe DataGridViewColumn

Aggiornamento: novembre 2007

Rappresenta una colonna in un controllo DataGridView.

Spazio dei nomi:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public class DataGridViewColumn : DataGridViewBand, 
	IComponent, IDisposable
public class DataGridViewColumn extends DataGridViewBand implements IComponent, 
	IDisposable
public class DataGridViewColumn extends DataGridViewBand implements IComponent, IDisposable

La classe DataGridViewColumn rappresenta una colonna logica in un controllo DataGridView. È possibile recuperare le colonne mediante l'insieme Columns del controllo.

A differenza della classe DataGridViewRow, che contiene l'insieme effettivo di celle in una classe DataGridView, la classe DataGridViewColumn viene utilizzata principalmente per la regolazione dell'aspetto e del comportamento dell'interfaccia utente (UI) della colonna, ad esempio la larghezza della colonna e lo stile della cella. Per ulteriori informazioni sugli stili delle celle, vedere Stili della cella nel controllo DataGridView Windows Form

I tipi che derivano dalla classe DataGridViewColumn solitamente inizializzano la proprietà CellTemplate a una nuova istanza del tipo correlato derivato dalla classe DataGridViewCell. Le proprietà della colonna relative all'aspetto o al comportamento di singole celle sono wrapper per le proprietà corrispondenti della cella modello. La modifica di una di queste proprietà nella colonna, modifica automaticamente il valore nel modello di cella e nelle celle nella colonna. Per eseguire l'override del valore specificato per singole celle, impostare i valori delle celle dopo aver impostato il valore della colonna.

Note per gli eredi:

Quando si deriva dalla classe DataGridViewColumn e si aggiungono nuove proprietà alla classe derivata, accertarsi di eseguire l'override del metodo Clone per copiare le nuove proprietà durante le operazioni di duplicazione. È necessario inoltre chiamare il metodo Clone della classe base in modo che le proprietà della classe base vengano copiate nella nuova cella.

Nell'esempio di codice riportato di seguito viene creato un Windows Form con una classe DataGridView e un insieme di pulsanti. Ciascuna etichetta di pulsante descrive l'operazione correlata a una proprietà DataGridViewColumn, ad esempio lo scambio della prima e dell'ultima colonna (mediante la proprietà DisplayIndex) o la modifica del testo di un'intestazione di colonna (mediante la proprietà HeaderText). Facendo clic su un pulsante, viene modificata la proprietà associata alla classe DataGridViewColumn.

using System.Windows.Forms;
using System;
using System.Drawing;

public class DataGridViewColumnDemo : Form
{
    #region "set up form"
    public DataGridViewColumnDemo()
    {
        InitializeComponent();

        AddButton(Button1, "Reset",
            new EventHandler(ResetToDisorder));
        AddButton(Button2, "Change Column 3 Header",
            new EventHandler(ChangeColumn3Header));
        AddButton(Button3, "Change Meatloaf Recipe",
            new EventHandler(ChangeMeatloafRecipe));
        AddAdditionalButtons();

        InitializeDataGridView();
    }

    DataGridView dataGridView;
    Button Button1 = new Button();
    Button Button2 = new Button();
    Button Button3 = new Button();
    Button Button4 = new Button();
    Button Button5 = new Button();
    Button Button6 = new Button();
    Button Button7 = new Button();
    Button Button8 = new Button();
    Button Button9 = new Button();
    Button Button10 = new Button();
    FlowLayoutPanel FlowLayoutPanel1 = new FlowLayoutPanel();

    private void InitializeComponent()
    {
        FlowLayoutPanel1.Location = new Point(454, 0);
        FlowLayoutPanel1.AutoSize = true;
        FlowLayoutPanel1.FlowDirection = FlowDirection.TopDown;
        FlowLayoutPanel1.Name = "flowlayoutpanel";
        ClientSize = new System.Drawing.Size(614, 360);
        Controls.Add(this.FlowLayoutPanel1);
        Text = this.GetType().Name;
        AutoSize = true;
    }
    #endregion

    #region "set up DataGridView"

    private string thirdColumnHeader = "Main Ingredients";
    private string boringMeatloaf = "ground beef";
    private string boringMeatloafRanking = "*";
    private bool boringRecipe;
    private bool shortMode;

    private void InitializeDataGridView()
    {
        dataGridView = new System.Windows.Forms.DataGridView();
        Controls.Add(dataGridView);
        dataGridView.Size = new Size(300, 200);

        // Create an unbound DataGridView by declaring a
        // column count.
        dataGridView.ColumnCount = 4;
        AdjustDataGridViewSizing();

        // Set the column header style.
        DataGridViewCellStyle columnHeaderStyle =
            new DataGridViewCellStyle();
        columnHeaderStyle.BackColor = Color.Aqua;
        columnHeaderStyle.Font =
            new Font("Verdana", 10, FontStyle.Bold);
        dataGridView.ColumnHeadersDefaultCellStyle =
            columnHeaderStyle;

        // Set the column header names.
        dataGridView.Columns[0].Name = "Recipe";
        dataGridView.Columns[1].Name = "Category";
        dataGridView.Columns[2].Name = thirdColumnHeader;
        dataGridView.Columns[3].Name = "Rating";

        PostColumnCreation();

        // Populate the rows.
        string[] row1 = new string[]{"Meatloaf", 
                                        "Main Dish", boringMeatloaf, boringMeatloafRanking};
        string[] row2 = new string[]{"Key Lime Pie", 
                                        "Dessert", "lime juice, evaporated milk", "****"};
        string[] row3 = new string[]{"Orange-Salsa Pork Chops", 
                                        "Main Dish", "pork chops, salsa, orange juice", "****"};
        string[] row4 = new string[]{"Black Bean and Rice Salad", 
                                        "Salad", "black beans, brown rice", "****"};
        string[] row5 = new string[]{"Chocolate Cheesecake", 
                                        "Dessert", "cream cheese", "***"};
        string[] row6 = new string[]{"Black Bean Dip", "Appetizer",
                                        "black beans, sour cream", "***"};
        object[] rows = new object[] { row1, row2, row3, row4, row5, row6 };

        foreach (string[] rowArray in rows)
        {
            dataGridView.Rows.Add(rowArray);
        }

        shortMode = false;
        boringRecipe = true;
    }

    private void AddButton(Button button, string buttonLabel,
        EventHandler handler)
    {
        FlowLayoutPanel1.Controls.Add(button);
        button.TabIndex = FlowLayoutPanel1.Controls.Count;
        button.Text = buttonLabel;
        button.AutoSize = true;
        button.Click += handler;
    }

    private void ResetToDisorder(object sender, System.EventArgs e)
    {
        Controls.Remove(dataGridView);
        dataGridView.Dispose();
        InitializeDataGridView();
    }

    private void ChangeColumn3Header(object sender,
        System.EventArgs e)
    {
        Toggle(ref shortMode);
        if (shortMode)
        { dataGridView.Columns[2].HeaderText = "S"; }
        else
        { dataGridView.Columns[2].HeaderText = thirdColumnHeader; }
    }

    private static void Toggle(ref bool toggleThis)
    {
        toggleThis = !toggleThis;
    }

    private void ChangeMeatloafRecipe(object sender,
        System.EventArgs e)
    {
        Toggle(ref boringRecipe);
        if (boringRecipe)
        {
            SetMeatloaf(boringMeatloaf, boringMeatloafRanking);
        }
        else
        {
            string greatMeatloafRecipe =
                "1 lb. lean ground beef, " +
                "1/2 cup bread crumbs, 1/4 cup ketchup," +
                "1/3 tsp onion powder, " +
                "1 clove of garlic, 1/2 pack onion soup mix " +
                " dash of your favorite BBQ Sauce";
            SetMeatloaf(greatMeatloafRecipe, "***");
        }
    }

    private void SetMeatloaf(string recipe, string rating)
    {
        dataGridView.Rows[0].Cells[2].Value = recipe;
        dataGridView.Rows[0].Cells[3].Value = rating;
    }
    #endregion

    #region "demonstration code"
    private void PostColumnCreation()
    {
        AddContextLabel();
        AddCriteriaLabel();
        CustomizeCellsInThirdColumn();
        AddContextMenu();
        SetDefaultCellInFirstColumn();
        ToolTips();

        dataGridView.CellMouseEnter +=
            dataGridView_CellMouseEnter;
        dataGridView.AutoSizeColumnModeChanged +=
            dataGridView_AutoSizeColumnModeChanged;
    }

    private string criteriaLabel = "Column 3 sizing criteria: ";
    private void AddCriteriaLabel()
    {
        AddLabelToPanelIfNotAlreadyThere(criteriaLabel,
            criteriaLabel +
            dataGridView.Columns[2].AutoSizeMode.ToString() +
            ".");
    }

    private void AddContextLabel()
    {
        string labelName = "label";
        AddLabelToPanelIfNotAlreadyThere(labelName,
            "Use shortcut menu to change cell color.");
    }

    private void AddLabelToPanelIfNotAlreadyThere(
        string labelName, string labelText)
    {
        Label label;
        if (FlowLayoutPanel1.Controls[labelName] == null)
        {
            label = new Label();
            label.AutoSize = true;
            label.Name = labelName;
            label.BackColor = Color.Bisque;
            FlowLayoutPanel1.Controls.Add(label);
        }
        else
        {
            label = (Label)FlowLayoutPanel1.Controls[labelName];
        }
        label.Text = labelText;
    }

    private void CustomizeCellsInThirdColumn()
    {
        int thirdColumn = 2;
        DataGridViewColumn column =
            dataGridView.Columns[thirdColumn];
        DataGridViewCell cell = new DataGridViewTextBoxCell();

        cell.Style.BackColor = Color.Wheat;
        column.CellTemplate = cell;
    }

    ToolStripMenuItem toolStripItem1 = new ToolStripMenuItem();

    private void AddContextMenu()
    {
        toolStripItem1.Text = "Redden";
        toolStripItem1.Click += new EventHandler(toolStripItem1_Click);
        ContextMenuStrip strip = new ContextMenuStrip();
        foreach (DataGridViewColumn column in dataGridView.Columns)
        {

            column.ContextMenuStrip = strip;
            column.ContextMenuStrip.Items.Add(toolStripItem1);
        }
    }

    private DataGridViewCellEventArgs mouseLocation;

    // Change the cell's color.
    private void toolStripItem1_Click(object sender, EventArgs args)
    {
        dataGridView.Rows[mouseLocation.RowIndex]
            .Cells[mouseLocation.ColumnIndex].Style.BackColor
            = Color.Red;
    }

    // Deal with hovering over a cell.
    private void dataGridView_CellMouseEnter(object sender,
        DataGridViewCellEventArgs location)
    {
        mouseLocation = location;
    }

    private void SetDefaultCellInFirstColumn()
    {
        DataGridViewColumn firstColumn = dataGridView.Columns[0];
        DataGridViewCellStyle cellStyle =
            new DataGridViewCellStyle();
        cellStyle.BackColor = Color.Thistle;

        firstColumn.DefaultCellStyle = cellStyle;
    }


    private void ToolTips()
    {
        DataGridViewColumn firstColumn = dataGridView.Columns[0];
        DataGridViewColumn thirdColumn = dataGridView.Columns[2];
        firstColumn.ToolTipText =
            "This column uses a default cell.";
        thirdColumn.ToolTipText =
            "This column uses a template cell." +
            " Style changes to one cell apply to all cells.";
    }

    private void AddAdditionalButtons()
    {
        AddButton(Button4, "Set Minimum Width of Column Two",
            new EventHandler(Button4_Click));
        AddButton(Button5, "Set Width of Column One",
            new EventHandler(Button5_Click));
        AddButton(Button6, "Autosize Third Column",
            new EventHandler(Button6_Click));
        AddButton(Button7, "Add Thick Vertical Edge",
            new EventHandler(Button7_Click));
        AddButton(Button8, "Style and Number Columns",
            new EventHandler(Button8_Click));
        AddButton(Button9, "Change Column Header Text",
            new EventHandler(Button9_Click));
        AddButton(Button10, "Swap First and Last Columns",
            new EventHandler(Button10_Click));
    }

    private void AdjustDataGridViewSizing()
    {
        dataGridView.ColumnHeadersHeightSizeMode = 
            DataGridViewColumnHeadersHeightSizeMode.AutoSize;
    }

    //Set the minimum width.
    private void Button4_Click(object sender,
        System.EventArgs e)
    {
        DataGridViewColumn column = dataGridView.Columns[1];
        column.MinimumWidth = 40;
    }

    // Set the width.
    private void Button5_Click(object sender, System.EventArgs e)
    {
        DataGridViewColumn column = dataGridView.Columns[0];
        column.Width = 60;
    }


    // AutoSize the third column.
    private void Button6_Click(object sender,
        System.EventArgs e)
    {
        DataGridViewColumn column = dataGridView.Columns[2];
        column.AutoSizeMode = DataGridViewAutoSizeColumnMode.DisplayedCells;
    }

    // Set the vertical edge.
    private void Button7_Click(object sender,
        System.EventArgs e)
    {
        int thirdColumn = 2;
        DataGridViewColumn column =
            dataGridView.Columns[thirdColumn];
        column.DividerWidth = 10;
    }

    // Style and number columns.
    private void Button8_Click(object sender,
        EventArgs args)
    {
        DataGridViewCellStyle style = new DataGridViewCellStyle();
        style.Alignment =
            DataGridViewContentAlignment.MiddleCenter;
        style.ForeColor = Color.IndianRed;
        style.BackColor = Color.Ivory;

        foreach (DataGridViewColumn column in dataGridView.Columns)
        {
            column.HeaderCell.Value = column.Index.ToString();
            column.HeaderCell.Style = style;
        }
    }

    // Change the text in the column header.
    private void Button9_Click(object sender,
        EventArgs args)
    {
        foreach (DataGridViewColumn column in dataGridView.Columns)
        {

            column.HeaderText = String.Concat("Column ",
                column.Index.ToString());
        }
    }

    // Swap the last column with the first.
    private void Button10_Click(object sender, EventArgs args)
    {
        DataGridViewColumnCollection columnCollection = dataGridView.Columns;

        DataGridViewColumn firstVisibleColumn =
            columnCollection.GetFirstColumn(DataGridViewElementStates.Visible);
        DataGridViewColumn lastVisibleColumn =
            columnCollection.GetLastColumn(
                DataGridViewElementStates.Visible, DataGridViewElementStates.None);

        int firstColumn_sIndex = firstVisibleColumn.DisplayIndex;
        firstVisibleColumn.DisplayIndex = lastVisibleColumn.DisplayIndex;
        lastVisibleColumn.DisplayIndex = firstColumn_sIndex;
    }

    // Updated the criteria label.
    private void dataGridView_AutoSizeColumnModeChanged(object sender,
        DataGridViewAutoSizeColumnModeEventArgs args)
    {
        args.Column.DataGridView.Parent.
            Controls["flowlayoutpanel"].Controls[criteriaLabel].
            Text = criteriaLabel
            + args.Column.AutoSizeMode.ToString();
    }
    #endregion

    [STAThreadAttribute()]
    public static void Main()
    {
        Application.Run(new DataGridViewColumnDemo());
    }

}


Qualsiasi membro static (Shared in Visual Basic) pubblico di questo tipo è thread-safe. I membri di istanza non sono garantiti come thread-safe.

Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition , Windows XP Starter Edition, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

.NET Framework e .NET Compact Framework non supportano tutte le versioni di ciascuna piattaforma. Per un elenco delle versioni supportate, vedere Requisiti di sistema di .NET Framework.

.NET Framework

Supportato in: 3.5, 3.0, 2.0
Mostra: