在椭圆内正确显示文本

Question

我需要在 c# 中正确显示绘制的椭圆内的文本，目前我正在使用它。

e.Graphics.DrawString(this.Text, base.Font, new SolidBrush(_NormalColorA), this.ClientRectangle, GetStringFormat(this.TextAlign));

GetStringFormat 函数

static internal StringFormat GetStringFormat(ContentAlignment ctrlalign)
        {
            StringFormat strFormat = new StringFormat();
            switch (ctrlalign)
            {
                case ContentAlignment.MiddleCenter:
                    strFormat.LineAlignment = StringAlignment.Center;
                    strFormat.Alignment = StringAlignment.Center;
                    break;
                case ContentAlignment.MiddleLeft:
                    strFormat.LineAlignment = StringAlignment.Center;
                    strFormat.Alignment = StringAlignment.Near;
                    break;
                case ContentAlignment.MiddleRight:
                    strFormat.LineAlignment = StringAlignment.Center;
                    strFormat.Alignment = StringAlignment.Far;
                    break;
                case ContentAlignment.TopCenter:
                    strFormat.LineAlignment = StringAlignment.Near;
                    strFormat.Alignment = StringAlignment.Center;
                    break;
                case ContentAlignment.TopLeft:
                    strFormat.LineAlignment = StringAlignment.Near;
                    strFormat.Alignment = StringAlignment.Near;
                    break;
                case ContentAlignment.TopRight:
                    strFormat.LineAlignment = StringAlignment.Near;
                    strFormat.Alignment = StringAlignment.Far;
                    break;
                case ContentAlignment.BottomCenter:
                    strFormat.LineAlignment = StringAlignment.Far;
                    strFormat.Alignment = StringAlignment.Center;
                    break;
                case ContentAlignment.BottomLeft:
                    strFormat.LineAlignment = StringAlignment.Far;
                    strFormat.Alignment = StringAlignment.Near;
                    break;
                case ContentAlignment.BottomRight:
                    strFormat.LineAlignment = StringAlignment.Far;
                    strFormat.Alignment = StringAlignment.Far;
                    break;
            }

            strFormat.HotkeyPrefix = System.Drawing.Text.HotkeyPrefix.None;

            return strFormat;
        }

在下面的图片中，您可以看到问题和预期，有什么想法吗？

Answer 1

由于椭圆在几何上等同于线性缩放的圆，并且由于您的长轴和短轴始终与 X 轴和 Y 轴对齐，因此最大化文本可用区域的内部矩形可以是只需将椭圆的总宽度和高度乘以 sqrt(2)/2.

给定一个描述椭圆的矩形，此函数应该为您的文本计算正确的布局矩形：

private static RectangleF GetEllipseInnerRect(RectangleF ellipse) {
    const float HalfSqrt2 = 0.707107f;
    var innerSize = new SizeF(ellipse.Width * HalfSqrt2, ellipse.Height * HalfSqrt2);
    return new RectangleF(
        ellipse.Left + 0.5f * (ellipse.Width - innerSize.Width),
        ellipse.Top + 0.5f * (ellipse.Height - innerSize.Height),
        innerSize.Width,
        innerSize.Height);
}

在椭圆内正确显示文本

Display text properly within ellipse

c#

.net

winforms

system.drawing