Error converting image to byte for saving in database

Question

I have a win form with picture box and i want to store image to database so while converting image to byte to store in database I am getting the error.How to solve the error? Here is my code and I have also pointed out the line at which error (object reference not set to instance of object) occurs:

   public string ImageToBase64(Image image,
      System.Drawing.Imaging.ImageFormat format)
    {
        using (MemoryStream ms = new MemoryStream())
        {
            // Convert Image to byte[]
            image.Save(ms, format);-------Error at this point----
            byte[] imageBytes = ms.ToArray();

            // Convert byte[] to Base64 String
            string base64String = Convert.ToBase64String(imageBytes);
            return base64String;
        }
    }

Possible duplicate of [What is a NullReferenceException, and how do I fix it?](http://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-and-how-do-i-fix-it) — ASh, Jun 01 '16 at 06:35

Pushpendra · Accepted Answer · 2016-06-01T07:53:41.973

1

Instead of

   using (MemoryStream ms = new MemoryStream())
    {
        // Convert Image to byte[]
        image.Save(ms, format);-------Error at this point----
        byte[] imageBytes = ms.ToArray();
          ..
     }

It should be:

    using(var ms = new MemoryStream())
    {
        image.Save(ms, image.RawFormat);
        byte[] imageBytes = ms.ToArray();

    }

RawFormat property of image returns the format of image

EDIT 1

You could also try to use ImageConverter class

 ImageConverter converter = new ImageConverter();
 byte[] imageBytes= (byte[])converter.ConvertTo(img, typeof(byte[]));

EDIT 2

If you are saving bytearray in your database table then the columntype should be VARBINARY Else if you are saving base64string it should be VARCHAR(MAX) or VARCHAR(X)

edited Jun 01 '16 at 07:53

answered Jun 01 '16 at 06:40

Pushpendra

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Still not working.Now its showing error at image.Save(ms, image.RawFormat); this point. – Sumit Bhattarai Jun 01 '16 at 06:46
While you are debugging, at any point before image.Save(ms, image.RawFormat);, have you checked whether image is null? – Pushpendra Jun 01 '16 at 06:51
Yeah before also in my code also it was showing error at the same line.How to remove that error?? – Sumit Bhattarai Jun 01 '16 at 06:54
I suspect it is other function which is calling this ImageToBase64(...) is culprit. If you could post the code which is calling this I might be able to help you. – Pushpendra Jun 01 '16 at 06:57
conn.Sqlquery("Insert into Admission values('" + btnStudentName.Text + "','" +Convert.ToDateTime (dateTimePicker1.Text) + "','" + btnGender.Text + "','" + btnSemester.Text + "','" + btnSession.Text + "','" + btnHSSBoard.Text + "','" + ImageToBase64(pictureBox2.Image, System.Drawing.Imaging.ImageFormat.Gif) + "')"); – Sumit Bhattarai Jun 01 '16 at 07:12
That helped but now its showing ''String or binary data would be truncated'' at cmd.executenonquery() point. – Sumit Bhattarai Jun 01 '16 at 07:40
The column in which you are inserting your bytearray should be "VARBINARY" in your SQL table. – Pushpendra Jun 01 '16 at 07:44
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/113494/discussion-between-pushpendra-and-sumit-bhattarai). – Pushpendra Jun 01 '16 at 09:45

Error converting image to byte for saving in database

1 Answers1