如何：擴充儲存格和資料行的行為和外觀以自訂 Windows Form DataGridView 控制項中的儲存格和資料行

發行項
06/02/2023

DataGridView 控制項提供數種方法使用屬性、事件和附屬類別來自訂其外觀和行為。有時候除了這些功能可提供的以外，您可能有對於儲存格的更多需求。您可以建立自己的自訂 DataGridViewCell 類別來提供擴充功能。

藉由衍生自 DataGridViewCell 基底類別或其中一個衍生的類別，您可建立自訂的 DataGridViewCell 類別。雖然您可以在任何類型的資料行中顯示任何類型的儲存格，您通常也會建立自訂的 DataGridViewColumn 類別，專門用於顯示儲存格類型。資料行類別衍生自 DataGridViewColumn 或其衍生類型之一。

在下列程式碼範例中，您將建立自訂儲存格類別，稱為 DataGridViewRolloverCell，偵測滑鼠何時進入及離開儲存格邊界。當滑鼠在儲存格的邊界內時，會繪製內凹矩形。這個新的類型衍生自 DataGridViewTextBoxCell，在其他方面的行為如同其基底類別。附屬資料行類別稱為 DataGridViewRolloverColumn。

若要使用這些類別，請建立一個表單，其中包含 DataGridView 控制項，以及加入一個以上的 DataGridViewRolloverColumn 物件到 Columns 集合，並在控制項填入包含值的資料列。

注意

如果您加入空白資料列，此範例將無法正確運作。例如當您藉由設定 RowCount 屬性加入資料列至控制項時，會建立空白資料列。這是因為在此情況下加入的資料列會自動共用，這表示 DataGridViewRolloverCell 物件不會具現化，直到您按一下個別的儲存格，因而導致相關的資料列變成非共用的。

因為自訂這種類型的儲存格需要非共用的資料列，所以它並不適用於大型資料集的使用。如需資料列共用的詳細資訊，請參閱調整 Windows Forms DataGridView 控制項的最佳做法。

注意

當您自 DataGridViewCell 或 DataGridViewColumn 中衍生時，以及在衍生類別中加入新的屬性時，請務必覆寫 Clone 方法，在複製作業期間複製新的屬性。您也應該呼叫基底類別的 Clone 方法，以便將基底類別的屬性複製到新的儲存格或資料行。

若要自訂 DataGridView 控制項中的資料格和資料行

從 DataGridViewTextBoxCell 類型衍生新的儲存格類別，稱為 DataGridViewRolloverCell。

public class DataGridViewRolloverCell : DataGridViewTextBoxCell
{

Public Class DataGridViewRolloverCell
    Inherits DataGridViewTextBoxCell

End Class

覆寫 Paint 類別中的 DataGridViewRolloverCell 方法。在覆寫時，先呼叫基底類別實作，這會處理裝載的文字方塊功能。然後使用控制項的 PointToClient 方法，將游標位置 (以螢幕座標表示) 轉換為 DataGridView 工作區座標。如果滑鼠座標落在儲存格的邊界內，則繪製內凹矩形。

protected override void Paint(
    Graphics graphics,
    Rectangle clipBounds,
    Rectangle cellBounds,
    int rowIndex,
    DataGridViewElementStates cellState,
    object value,
    object formattedValue,
    string errorText,
    DataGridViewCellStyle cellStyle,
    DataGridViewAdvancedBorderStyle advancedBorderStyle,
    DataGridViewPaintParts paintParts)
{
    // Call the base class method to paint the default cell appearance.
    base.Paint(graphics, clipBounds, cellBounds, rowIndex, cellState,
        value, formattedValue, errorText, cellStyle,
        advancedBorderStyle, paintParts);

    // Retrieve the client location of the mouse pointer.
    Point cursorPosition =
        this.DataGridView.PointToClient(Cursor.Position);

    // If the mouse pointer is over the current cell, draw a custom border.
    if (cellBounds.Contains(cursorPosition))
    {
        Rectangle newRect = new Rectangle(cellBounds.X + 1,
            cellBounds.Y + 1, cellBounds.Width - 4,
            cellBounds.Height - 4);
        graphics.DrawRectangle(Pens.Red, newRect);
    }
}

Protected Overrides Sub Paint( _
    ByVal graphics As Graphics, _
    ByVal clipBounds As Rectangle, _
    ByVal cellBounds As Rectangle, _
    ByVal rowIndex As Integer, _
    ByVal elementState As DataGridViewElementStates, _
    ByVal value As Object, _
    ByVal formattedValue As Object, _
    ByVal errorText As String, _
    ByVal cellStyle As DataGridViewCellStyle, _
    ByVal advancedBorderStyle As DataGridViewAdvancedBorderStyle, _
    ByVal paintParts As DataGridViewPaintParts)

    ' Call the base class method to paint the default cell appearance.
    MyBase.Paint(graphics, clipBounds, cellBounds, rowIndex, elementState, _
        value, formattedValue, errorText, cellStyle, _
        advancedBorderStyle, paintParts)

    ' Retrieve the client location of the mouse pointer.
    Dim cursorPosition As Point = _
        Me.DataGridView.PointToClient(Cursor.Position)

    ' If the mouse pointer is over the current cell, draw a custom border.
    If cellBounds.Contains(cursorPosition) Then
        Dim newRect As New Rectangle(cellBounds.X + 1, _
            cellBounds.Y + 1, cellBounds.Width - 4, _
            cellBounds.Height - 4)
        graphics.DrawRectangle(Pens.Red, newRect)
    End If

End Sub

覆寫 DataGridViewRolloverCell 類別中的 OnMouseEnter 和 OnMouseLeave 方法，當滑鼠指標進入或離開儲存格時，強制重新繪製儲存格。

// Force the cell to repaint itself when the mouse pointer enters it.
protected override void OnMouseEnter(int rowIndex)
{
    this.DataGridView.InvalidateCell(this);
}

// Force the cell to repaint itself when the mouse pointer leaves it.
protected override void OnMouseLeave(int rowIndex)
{
    this.DataGridView.InvalidateCell(this);
}

' Force the cell to repaint itself when the mouse pointer enters it.
Protected Overrides Sub OnMouseEnter(ByVal rowIndex As Integer)
    Me.DataGridView.InvalidateCell(Me)
End Sub

' Force the cell to repaint itself when the mouse pointer leaves it.
Protected Overrides Sub OnMouseLeave(ByVal rowIndex As Integer)
    Me.DataGridView.InvalidateCell(Me)
End Sub

從 DataGridViewColumn 類型衍生新的類別，稱為 DataGridViewRolloverCellColumn。在建構函式中，指派新的 DataGridViewRolloverCell 物件至其 CellTemplate 屬性。

public class DataGridViewRolloverCellColumn : DataGridViewColumn
{
    public DataGridViewRolloverCellColumn()
    {
        this.CellTemplate = new DataGridViewRolloverCell();
    }
}

Public Class DataGridViewRolloverCellColumn
    Inherits DataGridViewColumn

    Public Sub New()
        Me.CellTemplate = New DataGridViewRolloverCell()
    End Sub

End Class

範例

完整的程式碼範例包含小型測試表單，會示範自訂儲存格類型的行為。

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

class Form1 : Form
{
    [STAThreadAttribute()]
    public static void Main()
    {
        Application.Run(new Form1());
    }

    public Form1()
    {
        DataGridView dataGridView1 = new DataGridView();
        DataGridViewRolloverCellColumn col =
            new DataGridViewRolloverCellColumn();
        dataGridView1.Columns.Add(col);
        dataGridView1.Rows.Add(new string[] { "" });
        dataGridView1.Rows.Add(new string[] { "" });
        dataGridView1.Rows.Add(new string[] { "" });
        dataGridView1.Rows.Add(new string[] { "" });
        this.Controls.Add(dataGridView1);
        this.Text = "DataGridView rollover-cell demo";
    }
}

public class DataGridViewRolloverCell : DataGridViewTextBoxCell
{
    protected override void Paint(
        Graphics graphics,
        Rectangle clipBounds,
        Rectangle cellBounds,
        int rowIndex,
        DataGridViewElementStates cellState,
        object value,
        object formattedValue,
        string errorText,
        DataGridViewCellStyle cellStyle,
        DataGridViewAdvancedBorderStyle advancedBorderStyle,
        DataGridViewPaintParts paintParts)
    {
        // Call the base class method to paint the default cell appearance.
        base.Paint(graphics, clipBounds, cellBounds, rowIndex, cellState,
            value, formattedValue, errorText, cellStyle,
            advancedBorderStyle, paintParts);

        // Retrieve the client location of the mouse pointer.
        Point cursorPosition =
            this.DataGridView.PointToClient(Cursor.Position);

        // If the mouse pointer is over the current cell, draw a custom border.
        if (cellBounds.Contains(cursorPosition))
        {
            Rectangle newRect = new Rectangle(cellBounds.X + 1,
                cellBounds.Y + 1, cellBounds.Width - 4,
                cellBounds.Height - 4);
            graphics.DrawRectangle(Pens.Red, newRect);
        }
    }

    // Force the cell to repaint itself when the mouse pointer enters it.
    protected override void OnMouseEnter(int rowIndex)
    {
        this.DataGridView.InvalidateCell(this);
    }

    // Force the cell to repaint itself when the mouse pointer leaves it.
    protected override void OnMouseLeave(int rowIndex)
    {
        this.DataGridView.InvalidateCell(this);
    }

}

public class DataGridViewRolloverCellColumn : DataGridViewColumn
{
    public DataGridViewRolloverCellColumn()
    {
        this.CellTemplate = new DataGridViewRolloverCell();
    }
}

Imports System.Drawing
Imports System.Windows.Forms

Class Form1
    Inherits Form

    <STAThreadAttribute()> _
    Public Shared Sub Main()
        Application.Run(New Form1())
    End Sub

    Public Sub New()
        Dim dataGridView1 As New DataGridView()
        Dim col As New DataGridViewRolloverCellColumn()
        dataGridView1.Columns.Add(col)
        dataGridView1.Rows.Add(New String() {""})
        dataGridView1.Rows.Add(New String() {""})
        dataGridView1.Rows.Add(New String() {""})
        dataGridView1.Rows.Add(New String() {""})
        Me.Controls.Add(dataGridView1)
        Me.Text = "DataGridView rollover-cell demo"
    End Sub

End Class

Public Class DataGridViewRolloverCell
    Inherits DataGridViewTextBoxCell

    Protected Overrides Sub Paint( _
        ByVal graphics As Graphics, _
        ByVal clipBounds As Rectangle, _
        ByVal cellBounds As Rectangle, _
        ByVal rowIndex As Integer, _
        ByVal elementState As DataGridViewElementStates, _
        ByVal value As Object, _
        ByVal formattedValue As Object, _
        ByVal errorText As String, _
        ByVal cellStyle As DataGridViewCellStyle, _
        ByVal advancedBorderStyle As DataGridViewAdvancedBorderStyle, _
        ByVal paintParts As DataGridViewPaintParts)

        ' Call the base class method to paint the default cell appearance.
        MyBase.Paint(graphics, clipBounds, cellBounds, rowIndex, elementState, _
            value, formattedValue, errorText, cellStyle, _
            advancedBorderStyle, paintParts)

        ' Retrieve the client location of the mouse pointer.
        Dim cursorPosition As Point = _
            Me.DataGridView.PointToClient(Cursor.Position)

        ' If the mouse pointer is over the current cell, draw a custom border.
        If cellBounds.Contains(cursorPosition) Then
            Dim newRect As New Rectangle(cellBounds.X + 1, _
                cellBounds.Y + 1, cellBounds.Width - 4, _
                cellBounds.Height - 4)
            graphics.DrawRectangle(Pens.Red, newRect)
        End If

    End Sub

    ' Force the cell to repaint itself when the mouse pointer enters it.
    Protected Overrides Sub OnMouseEnter(ByVal rowIndex As Integer)
        Me.DataGridView.InvalidateCell(Me)
    End Sub

    ' Force the cell to repaint itself when the mouse pointer leaves it.
    Protected Overrides Sub OnMouseLeave(ByVal rowIndex As Integer)
        Me.DataGridView.InvalidateCell(Me)
    End Sub

End Class

Public Class DataGridViewRolloverCellColumn
    Inherits DataGridViewColumn

    Public Sub New()
        Me.CellTemplate = New DataGridViewRolloverCell()
    End Sub

End Class

編譯程式碼

這個範例需要：

System、System.Windows.Forms 和 System.Drawing 組件的參考。

Share via

如何：擴充儲存格和資料行的行為和外觀以自訂 Windows Form DataGridView 控制項中的儲存格和資料行

若要自訂 DataGridView 控制項中的資料格和資料行

範例

編譯程式碼

另請參閱

意見反應

其他資源