圖片處理

改變大小

※會轉為 jpeg 格式

public static byte[] resizeImage(byte[] imagearray, int maxsize)

{

using (var ms = new System.IO.MemoryStream(imagearray))

using (var image = (Image)new Bitmap(Image.FromStream(ms)))

{

decimal scale = ((decimal)image.Width) / image.Height;

Size size = default;

if (scale > 1)

{

int w = maxsize;

int h = (int)(w / scale);

size = new Size(w, h);

}

else

{

int h = maxsize;

int w = (int)(h * scale);

size = new Size(w, h);

}

byte[] arr;

Bitmap bmp = new Bitmap(image, size);

using (var ms1 = new System.IO.MemoryStream())

{

bmp.Save(ms1, ImageFormat.Jpeg);

arr = ms1.ToArray();

return arr;

}

}

}

寫入文字

var newBitmap = new Bitmap(image.Width, (int)(image.Height + fontsize));

newBitmap.SetResolution(image.HorizontalResolution, image.VerticalResolution);

using (Graphics graphics = Graphics.FromImage(newBitmap))

{

graphics.Clear(Color.White);

graphics.DrawImage(image, 0, 0);

using (Font font = new Font(fontname, fontsize, GraphicsUnit.Pixel))

{

var size = graphics.MeasureString(text, font);

var rect = new RectangleF(x, y, size.Width, size.Height);

graphics.FillRectangle(Brushes.White, rect);

graphics.DrawString(text, font, Brushes.Blue, new PointF(image.Width / 2 - fontsize * 13 / 3, image.Height - size.Height / 2));

}

}

文字轉圖片

Bitmap bmp = new Bitmap(width, Height);

using (Graphics graphics = Graphics.FromImage(bmp))

using (Font font = new Font(fontname, fontsize))

{

graphics.FillRectangle(new SolidBrush(bgcolor), 0, 0, bmp.Width, bmp.Height);

graphics.DrawString(txt, font, new SolidBrush(fcolor), 0, 0);

graphics.Flush();

}