Задача
Для каждой ячейки необходимо учитывать несколько факторов:
- DataGridViewContentAlignment .
- Точный размер выделенных символов.
- Символы нулевой ширины (пробелы).
- Размер содержимого.
- Пустое пространство.
- Индекс первого вхождения строки поиска.
Все перечисленное необходимо для вычисления и корректировки как местоположения, так и размера выделения. прямоугольник.
Вот пример:
RTL Languages - RTL Layout
private void dgv_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
{
if (txtSearch.TextLength < 1
|| e.RowIndex < 0
|| e.ColumnIndex < 1
|| e.Value == null)
return;
var zeroWidth = "|";
var v = e.Value.ToString().Replace(" ", zeroWidth);
var f = txtSearch.Text.Replace(" ", zeroWidth);
var i = v.IndexOf(f, StringComparison.InvariantCultureIgnoreCase);
if (i < 0) return;
e.Handled = true;
var g = e.Graphics;
using (var sf = ToStringFormat(e.CellStyle.Alignment))
{
var zw = g.MeasureString(zeroWidth, e.CellStyle.Font, e.CellBounds.Width, sf).Width;
var valWidth = g.MeasureString(v, e.CellStyle.Font, e.CellBounds.Width, sf).Width;
var w = g.MeasureString(f, e.CellStyle.Font, e.CellBounds.Width, sf).Width;
var x = e.CellBounds.Right - ((e.CellBounds.Width - valWidth) / 2);
x -= g.MeasureString(v.Substring(0, i), e.CellStyle.Font,
e.CellBounds.Width, sf).Width;
x -= w;
switch (e.CellStyle.Alignment)
{
case DataGridViewContentAlignment.BottomLeft:
case DataGridViewContentAlignment.MiddleLeft:
case DataGridViewContentAlignment.TopLeft:
x += ((e.CellBounds.Width - valWidth) / 2) - zw;
break;
case DataGridViewContentAlignment.MiddleRight:
case DataGridViewContentAlignment.BottomRight:
case DataGridViewContentAlignment.TopRight:
x -= ((e.CellBounds.Width - valWidth) / 2) - zw;
break;
default:
break;
}
var r = new RectangleF(
x,
e.CellBounds.Y + 3,
w,
e.CellBounds.Height - 7);
e.PaintBackground(e.CellBounds, true);
g.FillRectangle(Brushes.Yellow, r);
e.PaintContent(e.CellBounds);
}
}
private StringFormat ToStringFormat(DataGridViewContentAlignment ca)
{
var sf = StringFormat.GenericTypographic;
switch (ca)
{
case DataGridViewContentAlignment.MiddleCenter:
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Center;
break;
case DataGridViewContentAlignment.MiddleLeft:
sf.Alignment = StringAlignment.Near;
sf.LineAlignment = StringAlignment.Center;
break;
case DataGridViewContentAlignment.MiddleRight:
sf.Alignment = StringAlignment.Far;
sf.LineAlignment = StringAlignment.Center;
break;
case DataGridViewContentAlignment.BottomCenter:
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Far;
break;
case DataGridViewContentAlignment.BottomLeft:
sf.Alignment = StringAlignment.Near;
sf.LineAlignment = StringAlignment.Far;
break;
case DataGridViewContentAlignment.BottomRight:
sf.Alignment = StringAlignment.Far;
sf.LineAlignment = StringAlignment.Far;
break;
case DataGridViewContentAlignment.TopLeft:
sf.Alignment = StringAlignment.Near;
sf.LineAlignment = StringAlignment.Near;
break;
case DataGridViewContentAlignment.TopRight:
sf.Alignment = StringAlignment.Far;
sf.LineAlignment = StringAlignment.Near;
break;
case DataGridViewContentAlignment.TopCenter:
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Near;
break;
}
sf.FormatFlags |= StringFormatFlags.DirectionRightToLeft;
return sf;
}
Вот демонстрация .
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Примечание: Только DGV настроен на макет RTL в демонстрационной версии.
Языки LTR - макет LTR
Возможно, выходит за рамки, но может быть кому-то полезно.
private void dgv_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
{
if (txtSearch.TextLength < 1
|| e.RowIndex < 0
|| e.ColumnIndex < 1
|| e.Value == null)
return;
var zeroWidth = "|";
var v = e.Value.ToString().Replace(" ", zeroWidth);
var f = txtSearch.Text.Replace(" ", zeroWidth);
var i = v.IndexOf(f, StringComparison.InvariantCultureIgnoreCase);
if (i < 0) return;
e.Handled = true;
var g = e.Graphics;
using (var sf = ToStringFormat(e.CellStyle.Alignment))
{
var zs = g.MeasureString(zeroWidth, e.CellStyle.Font,
e.CellBounds.Width, sf).Width;
var valWidth = g.MeasureString(v, e.CellStyle.Font,
e.CellBounds.Width, sf).Width;
var x = g.MeasureString(v.Substring(0, i), e.CellStyle.Font,
e.CellBounds.Width, sf).Width;
var w = g.MeasureString(v.Substring(i, f.Length), e.CellStyle.Font,
e.CellBounds.Width, sf).Width;
switch (e.CellStyle.Alignment)
{
case DataGridViewContentAlignment.MiddleCenter:
case DataGridViewContentAlignment.BottomCenter:
case DataGridViewContentAlignment.TopCenter:
x += (e.CellBounds.Width - valWidth) / 2;
x -= zs / 2;
break;
case DataGridViewContentAlignment.MiddleRight:
case DataGridViewContentAlignment.BottomRight:
case DataGridViewContentAlignment.TopRight:
x += (e.CellBounds.Width - valWidth);
x -= zs * 1.5f;
break;
default:
x += zs / 2;
break;
}
var r = new RectangleF(
e.CellBounds.X + x,
e.CellBounds.Y + 3,
w,
e.CellBounds.Height - 7);
e.PaintBackground(e.CellBounds, true);
g.FillRectangle(Brushes.Yellow, r);
e.PaintContent(e.CellBounds);
}
}
private StringFormat ToStringFormat(DataGridViewContentAlignment ca)
{
var sf = StringFormat.GenericTypographic;
switch (ca)
{
case DataGridViewContentAlignment.MiddleCenter:
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Center;
break;
case DataGridViewContentAlignment.MiddleLeft:
sf.Alignment = StringAlignment.Near;
sf.LineAlignment = StringAlignment.Center;
break;
case DataGridViewContentAlignment.MiddleRight:
sf.Alignment = StringAlignment.Far;
sf.LineAlignment = StringAlignment.Center;
break;
case DataGridViewContentAlignment.BottomCenter:
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Far;
break;
case DataGridViewContentAlignment.BottomLeft:
sf.Alignment = StringAlignment.Near;
sf.LineAlignment = StringAlignment.Far;
break;
case DataGridViewContentAlignment.BottomRight:
sf.Alignment = StringAlignment.Far;
sf.LineAlignment = StringAlignment.Far;
break;
case DataGridViewContentAlignment.TopLeft:
sf.Alignment = StringAlignment.Near;
sf.LineAlignment = StringAlignment.Near;
break;
case DataGridViewContentAlignment.TopRight:
sf.Alignment = StringAlignment.Far;
sf.LineAlignment = StringAlignment.Near;
break;
case DataGridViewContentAlignment.TopCenter:
sf.Alignment = StringAlignment.Center;
sf.LineAlignment = StringAlignment.Near;
break;
}
return sf;
}
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