How to save image as attachment in List using CSOM C#?

Question

I am using Microsoft Graph API to retrieve the user profile image and I want to save the retrieved image as an attachment in the list item. So I am using following code.

var response = await httpClient.GetAsync("https://graph.microsoft.com/v1.0/me/photo/$value");
var responsImage = response.Content.ReadAsStringAsync().Result;

Here, in responseImage I am able to get image content type. So I tried saving the image to my local drive using following code:

using (Stream responseStream = responsImage)
{
   using (FileStream fs = new FileStream(@"D:\image.jpg", FileMode.Create))
   {
       await responseStream.CopyToAsync(fs);
   }
}

After saving it to my local drive for testing the image, it gives me the proper image.

Now, I am trying to save the same image as an attachment as I am having an image in Stream object.

For saving image as an attachment I am using the code from here.

It saves the content as an attachment.

But when I open the attachment, it shows me the blank image instead of the correct image. As shown below:

I am not able to figure it out while saving its giving perfect image while using the same stream it saves the blank image.

What I am doing wrong?.

Answer 1

I have used this in PowrShell Scripts

May be it will help you

foreach($item in $Items)
{
   if($item.Attachments -ne $null)
 {


   try
   {
    foreach($attachment in $item.Attachments)
     {
      Write-Host "Downloading Attachement: " $attachment  -ForegroundColor Green
      $file= $w.GetFile($item.Attachments.UrlPrefix + $attachment)
      $bytes = $file.OpenBinary()
      $path = $destinationFolder + "\" + $attachment
      Write-Host ""
      Write "Saving to the loction  $path"
      $fs = New-Object System.IO.FileStream($path, "OpenOrCreate")
      $fs.Write($bytes,0,$bytes.Length)
      $fs.Close()

    } 
   }
   Catch
   {
    Write-Host " Error" -BackgroundColor DarkMagenta
   }
 }

}

Updated Answer

`

             List docs = web.Lists.GetByTitle("CustomList");
               ListItem item = docs.GetItemById(ID);
           var attInfo = new AttachmentCreationInformation();
        attInfo.FileName = mFile.Name;
        attInfo.ContentStream = new MemoryStream(System.IO.File.ReadAllBytes("streamFile"));

        Attachment att = item.AttachmentFiles.Add(attInfo); //Add to File

        context.Load(att);
        context.ExecuteQuery();
        Console.WriteLine("done");`

Answer 2

There 2 ways you can add attachments to list items.

Option 1 - .AttachmentFiles.Add(attachmentInfo) as below using FileStream:

var list = context.Web.Lists.GetByTitle("CustomList");
var listItem = list.GetItemById(7);
var path = @"C:\abcd.jpg";
var attachmentInfo = new AttachmentCreationInformation();
attachmentInfo.FileName = System.IO.Path.GetFileName(path);
using (var fs = new FileStream(path, FileMode.Open))
{
    attachmentInfo.ContentStream = fs;
    var attachment = listItem.AttachmentFiles.Add(attachmentInfo);
    context.ExecuteQuery();                    
}

Option 2 - using SaveBinaryDirect method. For that, you need to have ServerRelativeUrl of your SharePoint list. Try below code:

var list = context.Web.Lists.GetByTitle("CustomList");                
var attachFilePath = @"C:\abcd.jpg";
var listItem = list.GetItemById(4);
context.Load(listItem);
context.ExecuteQuery();
using (System.IO.FileStream fileStream = new System.IO.FileInfo(attachFilePath).Open(System.IO.FileMode.Open))
{
    Microsoft.SharePoint.Client.File.SaveBinaryDirect(context, "/sites/GautamTestSite/Lists/CustomList/Attachments/" + listItem.Id + "/" + System.IO.Path.GetFileName(attachFilePath), fileStream, true);
}