private static void drawString(
string text,
TextToImageOptions options,
Font font,
RectangleF rectangle,
Graphics graphics,
SolidBrush fgBrush)
{
using var format = new StringFormat
{
FormatFlags = StringFormatFlags.NoWrap,
Alignment = StringAlignment.Center
};
if (options.DropShadowLevel > 0)
{
using var brush = new SolidBrush(options.ShadowColor);
switch (options.DropShadowLevel)
{
case 1:
rectangle.Offset(-1, -1);
graphics.DrawString(text, font, brush, rectangle, format);
rectangle.Offset(+1, +1);
break;
case 2:
rectangle.Offset(+1, -1);
graphics.DrawString(text, font, brush, rectangle, format);
rectangle.Offset(-1, +1);
break;
case 3:
rectangle.Offset(-1, +1);
graphics.DrawString(text, font, brush, rectangle, format);
rectangle.Offset(+1, -1);
break;
case 4:
rectangle.Offset(+1, +1);
graphics.DrawString(text, font, brush, rectangle, format);
rectangle.Offset(-1, -1);
break;
}
}
graphics.DrawString(text, font, fgBrush, rectangle, format);
}
public static byte[] TextToImage(this string text, TextToImageOptions options)
{
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
using var family = new FontFamily(options.FontName);
using var font = new Font(family, options.FontSize, options.FontStyle, GraphicsUnit.Pixel);
var textSize = MeasureString(text, font);
int width = ((int)textSize.Width) + 5;
int height = ((int)textSize.Height) + 3;
var rectangle = new RectangleF(0, 0, width, height);
using var pic = new Bitmap(width, height);
using var graphics = Graphics.FromImage(pic);
graphics.SmoothingMode = SmoothingMode.AntiAlias;
graphics.SmoothingMode = SmoothingMode.HighQuality;
graphics.CompositingQuality = CompositingQuality.HighQuality;
graphics.InterpolationMode = InterpolationMode.High;
if (options.AntiAlias)
{
graphics.TextRenderingHint = TextRenderingHint.AntiAlias;
}
using var fgBrush = new SolidBrush(options.FontColor);
using var bgBrush = new SolidBrush(options.BgColor);
if (options.Rectangle)
{
graphics.FillRectangle(bgBrush, rectangle);
}
else
{
using var brush = new SolidBrush(Color.White);
graphics.FillRectangle(brush, rectangle);
graphics.FillEllipse(bgBrush, rectangle);
}
using var pen = new Pen(Color.LightGray);
graphics.DrawRectangle(pen, new Rectangle(0, 0, width - 1, height - 1));
drawString(text, options, font, rectangle, graphics, fgBrush);
using var memory = new MemoryStream();
pic.Save(memory, ImageFormat.Png);
return(memory.ToArray());
}
/// <summary>
/// Draws a text on a bitmap and then returns it as a png byte array.
/// </summary>
public static byte[] TextToImage(this string text, TextToImageOptions options)
{
using (Font font = new Font(new FontFamily(options.FontName), options.FontSize, options.FontStyle, GraphicsUnit.Pixel))
{
var textSize = MeasureString(text, font);
int width = ((int)textSize.Width) + 5;
int height = ((int)textSize.Height) + 3;
var rectangle = new RectangleF(0, 0, width, height);
using (Bitmap pic = new Bitmap(width, height))
{
using (Graphics graphics = Graphics.FromImage(pic))
{
graphics.SmoothingMode = SmoothingMode.AntiAlias;
graphics.SmoothingMode = SmoothingMode.HighQuality;
graphics.CompositingQuality = CompositingQuality.HighQuality;
graphics.InterpolationMode = InterpolationMode.High;
if (options.AntiAlias)
{
graphics.TextRenderingHint = TextRenderingHint.AntiAlias;
}
using (SolidBrush fgBrush = new SolidBrush(options.FontColor))
{
using (SolidBrush bgBrush = new SolidBrush(options.BgColor))
{
if (options.Rectangle)
{
graphics.FillRectangle(bgBrush, rectangle);
}
else
{
graphics.FillRectangle(new SolidBrush(Color.White), rectangle);
graphics.FillEllipse(bgBrush, rectangle);
}
graphics.DrawRectangle(new Pen(Color.LightGray), new Rectangle(0, 0, width - 1, height - 1));
using (StringFormat format = new StringFormat())
{
format.FormatFlags = StringFormatFlags.NoWrap;
format.Alignment = StringAlignment.Center;
if (options.DropShadowLevel > 0)
{
switch (options.DropShadowLevel)
{
case 1:
rectangle.Offset(-1, -1);
graphics.DrawString(text, font, new SolidBrush(options.ShadowColor), rectangle,
format);
rectangle.Offset(+1, +1);
break;
case 2:
rectangle.Offset(+1, -1);
graphics.DrawString(text, font, new SolidBrush(options.ShadowColor), rectangle,
format);
rectangle.Offset(-1, +1);
break;
case 3:
rectangle.Offset(-1, +1);
graphics.DrawString(text, font, new SolidBrush(options.ShadowColor), rectangle,
format);
rectangle.Offset(+1, -1);
break;
case 4:
rectangle.Offset(+1, +1);
graphics.DrawString(text, font, new SolidBrush(options.ShadowColor), rectangle,
format);
rectangle.Offset(-1, -1);
break;
}
}
graphics.DrawString(text, font, fgBrush, rectangle, format);
using (var memory = new MemoryStream())
{
pic.Save(memory, ImageFormat.Png);
return(memory.ToArray());
}
}
}
}
}
}
}
}
/// <summary>
/// An ASP.NET Core text to image renderer.
/// </summary>
public TextToImageResult(string text, TextToImageOptions options)
{
_options = options;
_text = text;
}
