更改DatagridviewCheckboxCell的checkBoxSize并增加可點擊區域

我的 .net 核心 Winform 資料 GridVew 中有一個復選框列。
我已經使復選框更大，以便用戶單擊。

我的代碼里面CellPainting，

                e.PaintBackground(e.CellBounds, true);
                ControlPaint.DrawCheckBox(e.Graphics, e.CellBounds.X   1, e.CellBounds.Y   5,
                    e.CellBounds.Width - 10, e.CellBounds.Height - 10,
                    (bool)e.FormattedValue ? ButtonState.Checked : ButtonState.Normal);
                e.Handled = true;

這些是我的參考鏈接，

但問題是點擊區域，即使復選框的大小更大，我意識到可點擊區域仍然是原來的大小。
如下所示，綠色區域是可點擊區域，

我想讓可點擊區域與復選框的大小一樣大，如下所示，

有什么解決辦法嗎？

uj5u.com熱心網友回復：

當您單擊滑鼠DataGridViewCheckBoxCell來切換Checked狀態時，您必須單擊單元格內的內容，單擊單元格內的其他位置不會改變任何事情。a 的內容DataGridViewCheckBoxCell就是那個小盒子區域。因此，僅繪制一個更大的框不會調整該內容DefaultCellStyle.Alignment區域的大小或重新定位（根據該列的），并且它保持不變。您需要為此撰寫代碼來說明，內容區域已被單擊，并且應該呼叫相關的基本方法和事件。

我會創建自定義DataGridViewCheckBox列和單元格來應用此要求。

在專案的命名空間中，從以下位置派生一個新類DataGridViewCheckBoxColumn：

public class CustomDataGridViewCheckBoxColumn : DataGridViewCheckBoxColumn
{
    public CustomDataGridViewCheckBoxColumn() : base() =>
        CellTemplate = new CustomDataGridViewCheckBoxCell();

    public override DataGridViewCell CellTemplate
    {
        get => base.CellTemplate;
        set
        {
            if (value != null &&
                !value.GetType().IsAssignableFrom(typeof(CustomDataGridViewCheckBoxCell)))
                throw new InvalidCastException("CustomDataGridViewCheckBoxCell.");

            base.CellTemplate = value;
        }
    }

    [Category("Appearance")]
    [DefaultValue(typeof(Size), "17, 17")]
    [Description("The size of the check box.")]
    public Size CheckBoxSize { get; set; } = new Size(17, 17);

    // We should copy the new properties.
    public override object Clone()
    {
        var c = base.Clone() as CustomDataGridViewCheckBoxColumn;
        c.CheckBoxSize = CheckBoxSize;
        return c;
    }
}

另一個來自DataGridViewCheckBoxCell：

public class CustomDataGridViewCheckBoxCell : DataGridViewCheckBoxCell
{
    private Rectangle curCellBounds;
    private Rectangle checkBoxRect;

    public CustomDataGridViewCheckBoxCell() : base() { }

    protected override void Paint(
        Graphics g,
        Rectangle clipBounds,
        Rectangle cellBounds,
        int rowIndex,
        DataGridViewElementStates elementState,
        object value,
        object formattedValue,
        string errorText,
        DataGridViewCellStyle cellStyle,
        DataGridViewAdvancedBorderStyle advancedBorderStyle,
        DataGridViewPaintParts paintParts)
    {
        // Paint default except the check box parts.
        var parts = paintParts & ~(DataGridViewPaintParts.ContentForeground 
            | DataGridViewPaintParts.ContentBackground);

        base.Paint(g, 
            clipBounds, 
            cellBounds, 
            rowIndex, 
            elementState, 
            value, 
            formattedValue, 
            errorText, 
            cellStyle, 
            advancedBorderStyle, 
            parts);
            
        if (curCellBounds != cellBounds)
        {
            // To get the box size...
            var col = OwningColumn as CustomDataGridViewCheckBoxColumn;

            curCellBounds = cellBounds;
            // ToDo: Use col.DefaultCellStyle.Alignment or
            // DataGridView.ColumnHeadersDefaultCellStyle.Alignment
            // to position the box. MiddleCenter here...
            checkBoxRect = new Rectangle(
                (cellBounds.Width - col.CheckBoxSize.Width) / 2   cellBounds.X,
                (cellBounds.Height - col.CheckBoxSize.Height) / 2   cellBounds.Y,
                col.CheckBoxSize.Width,
                col.CheckBoxSize.Height);
        }

        ControlPaint.DrawCheckBox(g, checkBoxRect, (bool)formattedValue 
            ? ButtonState.Checked | ButtonState.Flat 
            : ButtonState.Flat);
    }

    // In case you don't use the `Alignment` property to position the 
    // box. This is to disallow toggling the state if you click on the
    // original content area outside the drawn box.
    protected override void OnContentClick(DataGridViewCellEventArgs e)
    {
        if (!ReadOnly &&
            checkBoxRect.Contains(DataGridView.PointToClient(Cursor.Position)))
            base.OnContentClick(e);
    }

    protected override void OnContentDoubleClick(DataGridViewCellEventArgs e)
    {
        if (!ReadOnly &&
            checkBoxRect.Contains(DataGridView.PointToClient(Cursor.Position)))
            base.OnContentDoubleClick(e);
    }

    // Toggle the checked state by mouse clicks...
    protected override void OnMouseUp(DataGridViewCellMouseEventArgs e)
    {
        base.OnMouseUp(e);

        if (!ReadOnly && e.Button == MouseButtons.Left &&
            checkBoxRect.Contains(DataGridView.PointToClient(Cursor.Position)))
        {
            Value = Value == null || !Convert.ToBoolean(Value);
            DataGridView.RefreshEdit();
            DataGridView.NotifyCurrentCellDirty(true);
        }    
    }

    // ... and Space key...
    protected override void OnKeyDown(KeyEventArgs e, int rowIndex)
    {
        base.OnKeyDown(e, rowIndex);
        if (!ReadOnly && e.KeyCode == Keys.Space)
        {
            Value = Value == null || !Convert.ToBoolean(Value.ToString());
            DataGridView.RefreshEdit();
            DataGridView.NotifyCurrentCellDirty(true);
        }
    }
}

在網格設計器中重建并檢查新的列型別。

如果您有資料系結網格，請將AutoGenerateColumns屬性設定為false并手動添加列。例如：

private readonly static Random rnd = new Random();
//..

var dt = new DataTable();
dt.Columns.AddRange(new[]
{
    new DataColumn("Default", typeof(bool)),
    new DataColumn("Custom", typeof(bool))
});

for (int i = 1; i < 6; i  )
    dt.Rows.Add(rnd.Next(0, 2), rnd.Next(0, 2));

dataGridView1.AutoGenerateColumns = false;
dataGridView1.Columns.AddRange(new[]
{
    new DataGridViewCheckBoxColumn { HeaderText = "Default" },
    new CustomDataGridViewCheckBoxColumn 
    { 
        HeaderText = "Custom",
        CheckBoxSize = new Size(32, 32) 
    }
});
dataGridView1.DataSource = dt;

標籤：C＃ 表格 复选框 数据网格视图 数据网格视图复选框单元格

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