如何将字节数组转换为图像文件？

Question

I have browsed and uploaded a png/jpg file in my MVC web app. I have stored this file as byte[] in my database. Now I want to read and convert the byte[] to original file. How can i achieve this?

Answer 1

1. Create a MemoryStream passing the array in the constructor.
2. Read the image from the stream using Image.FromStream .
3. Call theImg.Save("theimage.jpg", ImageFormat.Jpeg) .

Remember to reference System.Drawing.Imaging and use a using block for the stream.

Answer 2

Create a memory stream from the byte[] array in your database and then use Image.FromStream.

byte[] image = GetImageFromDatabase();
MemoryStream ms = new MemoryStream(image);
Image i = Image.FromStream(ms);

Answer 3

May you have trouble with the mentioned solutions on DotNet Core 3.0 or higher
so my solution is:

using(var ms = new MemoryStream(yourByteArray)) {
   using(var fs = new FileStream("savePath", FileMode.Create)) {
      ms.WriteTo(fs);
   }
}

Answer 4

Or just use this:

System.IO.File.WriteAllBytes(string path, byte[] bytes)

File.WriteAllBytes(String, Byte[]) Method (System.IO) | Microsoft Docs