DataGridViewRowPrePaintEventArgs.DrawFocus(Rectangle, Boolean) Metodo

Definizione

Spazio dei nomi:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Origine:

DataGridViewRowPrePaintEventArgs.cs

Disegna il rettangolo di attivazione intorno ai limiti specificati.

public:
 void DrawFocus(System::Drawing::Rectangle bounds, bool cellsPaintSelectionBackground);

public void DrawFocus (System.Drawing.Rectangle bounds, bool cellsPaintSelectionBackground);

member this.DrawFocus : System.Drawing.Rectangle * bool -> unit

Public Sub DrawFocus (bounds As Rectangle, cellsPaintSelectionBackground As Boolean)

Parametri

bounds

Rectangle

Struttura Rectangle che specifica l'area attiva.

cellsPaintSelectionBackground

Boolean

true per utilizzare la proprietà SelectionBackColor della proprietà InheritedStyle per determinare il colore del rettangolo di attivazione; false per utilizzare la proprietà BackColor della proprietà InheritedStyle.

Eccezioni

InvalidOperationException

La proprietà RowIndex è minore di zero o maggiore del numero di righe nel controllo DataGridView meno 1.

Esempio

Nell'esempio di codice seguente viene illustrato come usare il DrawFocus metodo per disegnare uno stato attivo sulle celle visibili della riga. Il codice usa effettivamente il DataGridViewRowPostPaintEventArgs.DrawFocus metodo, che è quasi identico al DrawFocus metodo di DataGridViewRowPrePaintEventArgs. Questo esempio fa parte di un esempio più ampio disponibile in Procedura: Personalizzare l'aspetto delle righe nel controllo DataGridView Windows Forms.

// Paints the content that spans multiple columns and the focus rectangle.
void dataGridView1_RowPostPaint(object sender,
    DataGridViewRowPostPaintEventArgs e)
{
    // Calculate the bounds of the row.
    Rectangle rowBounds = new Rectangle(
        this.dataGridView1.RowHeadersWidth, e.RowBounds.Top,
        this.dataGridView1.Columns.GetColumnsWidth(
            DataGridViewElementStates.Visible) -
        this.dataGridView1.HorizontalScrollingOffset + 1,
        e.RowBounds.Height);

    SolidBrush forebrush = null;
    try
    {
        // Determine the foreground color.
        if ((e.State & DataGridViewElementStates.Selected) ==
            DataGridViewElementStates.Selected)
        {
            forebrush = new SolidBrush(e.InheritedRowStyle.SelectionForeColor);
        }
        else
        {
            forebrush = new SolidBrush(e.InheritedRowStyle.ForeColor);
        }

        // Get the content that spans multiple columns.
        object recipe =
            this.dataGridView1.Rows.SharedRow(e.RowIndex).Cells[2].Value;

        if (recipe != null)
        {
            String text = recipe.ToString();

            // Calculate the bounds for the content that spans multiple 
            // columns, adjusting for the horizontal scrolling position 
            // and the current row height, and displaying only whole
            // lines of text.
            Rectangle textArea = rowBounds;
            textArea.X -= this.dataGridView1.HorizontalScrollingOffset;
            textArea.Width += this.dataGridView1.HorizontalScrollingOffset;
            textArea.Y += rowBounds.Height - e.InheritedRowStyle.Padding.Bottom;
            textArea.Height -= rowBounds.Height -
                e.InheritedRowStyle.Padding.Bottom;
            textArea.Height = (textArea.Height / e.InheritedRowStyle.Font.Height) *
                e.InheritedRowStyle.Font.Height;

            // Calculate the portion of the text area that needs painting.
            RectangleF clip = textArea;
            clip.Width -= this.dataGridView1.RowHeadersWidth + 1 - clip.X;
            clip.X = this.dataGridView1.RowHeadersWidth + 1;
            RectangleF oldClip = e.Graphics.ClipBounds;
            e.Graphics.SetClip(clip);

            // Draw the content that spans multiple columns.
            e.Graphics.DrawString(
                text, e.InheritedRowStyle.Font, forebrush, textArea);

            e.Graphics.SetClip(oldClip);
        }
    }
    finally
    {
        forebrush.Dispose();
    }

    if (this.dataGridView1.CurrentCellAddress.Y == e.RowIndex)
    {
        // Paint the focus rectangle.
        e.DrawFocus(rowBounds, true);
    }
}

' Paints the content that spans multiple columns and the focus rectangle.
Sub dataGridView1_RowPostPaint(ByVal sender As Object, _
    ByVal e As DataGridViewRowPostPaintEventArgs) _
    Handles dataGridView1.RowPostPaint

    ' Calculate the bounds of the row.
    Dim rowBounds As New Rectangle(Me.dataGridView1.RowHeadersWidth, _
        e.RowBounds.Top, Me.dataGridView1.Columns.GetColumnsWidth( _
        DataGridViewElementStates.Visible) - _
        Me.dataGridView1.HorizontalScrollingOffset + 1, e.RowBounds.Height)

    Dim forebrush As SolidBrush = Nothing
    Try
        ' Determine the foreground color.
        If (e.State And DataGridViewElementStates.Selected) = _
            DataGridViewElementStates.Selected Then

            forebrush = New SolidBrush(e.InheritedRowStyle.SelectionForeColor)
        Else
            forebrush = New SolidBrush(e.InheritedRowStyle.ForeColor)
        End If

        ' Get the content that spans multiple columns.
        Dim recipe As Object = _
            Me.dataGridView1.Rows.SharedRow(e.RowIndex).Cells(2).Value

        If (recipe IsNot Nothing) Then
            Dim text As String = recipe.ToString()

            ' Calculate the bounds for the content that spans multiple 
            ' columns, adjusting for the horizontal scrolling position 
            ' and the current row height, and displaying only whole
            ' lines of text.
            Dim textArea As Rectangle = rowBounds
            textArea.X -= Me.dataGridView1.HorizontalScrollingOffset
            textArea.Width += Me.dataGridView1.HorizontalScrollingOffset
            textArea.Y += rowBounds.Height - e.InheritedRowStyle.Padding.Bottom
            textArea.Height -= rowBounds.Height - e.InheritedRowStyle.Padding.Bottom
            textArea.Height = (textArea.Height \ e.InheritedRowStyle.Font.Height) * _
                e.InheritedRowStyle.Font.Height

            ' Calculate the portion of the text area that needs painting.
            Dim clip As RectangleF = textArea
            clip.Width -= Me.dataGridView1.RowHeadersWidth + 1 - clip.X
            clip.X = Me.dataGridView1.RowHeadersWidth + 1
            Dim oldClip As RectangleF = e.Graphics.ClipBounds
            e.Graphics.SetClip(clip)

            ' Draw the content that spans multiple columns.
            e.Graphics.DrawString(text, e.InheritedRowStyle.Font, forebrush, _
                textArea)

            e.Graphics.SetClip(oldClip)
        End If
    Finally
        forebrush.Dispose()
    End Try

    If Me.dataGridView1.CurrentCellAddress.Y = e.RowIndex Then
        ' Paint the focus rectangle.
        e.DrawFocus(rowBounds, True)
    End If

End Sub

Commenti

Usare il DrawFocus metodo quando si disegna il contenuto delle DataGridViewRow celle. Se si disegna manualmente l'intera riga e il contenuto delle celle, impostare la HandledEventArgs.Handled proprietà su true. Quando HandledEventArgs.Handled è true, gli CellPainting eventi e RowPostPaint non si verificano.

Vedi anche

• DataGridView
• BackColor
• SelectionBackColor
• DataGridViewRow
• Handled