csharp 创建字符串图像

Posted 2021-05-12

private static string DrawText(String text)
{

    Font font = new Font("Arial", 1024, FontStyle.Bold);
    Color textColor = Color.White;
    Color backColor = Color.FromArgb(1, 143, 36, 174);

    //first, create a dummy bitmap just to get a graphics object
    Image img = new Bitmap(1, 1);
    Graphics drawing = Graphics.FromImage(img);

    //measure the string to see how big the image needs to be
    SizeF textSize = drawing.MeasureString(text, font);

    //free up the dummy image and old graphics object
    img.Dispose();
    drawing.Dispose();

    //create a new image of the right size
    img = new Bitmap((int)textSize.Width, (int)textSize.Height);

    drawing = Graphics.FromImage(img);
    drawing.SmoothingMode = SmoothingMode.HighQuality;
    drawing.InterpolationMode = InterpolationMode.HighQualityBicubic;
    drawing.PixelOffsetMode = PixelOffsetMode.HighQuality;

    //paint the background
    drawing.Clear(backColor);

    Brush rect = new SolidBrush(backColor);
    Rectangle rectangle = new Rectangle(0, 0, 200, 200);
    drawing.FillRectangle(rect, rectangle);
    
    //create a brush for the text
    Brush textBrush = new SolidBrush(textColor);

    drawing.DrawString(text, font, textBrush, 0, 0);

    drawing.Save();

    string base64;
    using (MemoryStream ms = new MemoryStream())
    {
        img.Save(ms, ImageFormat.Jpeg);
        base64 = Convert.ToBase64String(ms.ToArray());
    }

    textBrush.Dispose();
    drawing.Dispose();

    return base64;
}