Attach file in CustomList Item using Sharepoint.Client object

Question

Hi is there a way to attach file in specific Custom list item?

Currently i tried to add files on the root folder using below code:

using (ClientContext context = new ClientContext("http://SharepointURL/"))
{
    try
    {


        Web web = context.Web;

        FileCreationInformation newFile = new FileCreationInformation();
        newFile.Content = System.IO.File.ReadAllBytes(@"C:\test.txt");
        newFile.Url = "test.txt";

        List docs = web.Lists.GetByTitle("MyCustomList");
        ListItem item = docs.GetItemById(1);
        Microsoft.SharePoint.Client.File uploadFile = docs.RootFolder.Folders.GetByUrl("Attachments").Files.Add(newFile); //Save file on Attachment folder but not creating new attachment folder for ListItem
        context.Load(uploadFile);
        context.ExecuteQuery();
        Console.WriteLine("done");


    }
    catch (Exception ex)
    {
        throw ex;
    }
}

Any help is appreciated! Thanks!

Answer 1

I already solve my problem below is my code:

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");

Hope this helps other developers too. Regards!

Answer 2

This can be done by calling SPservice operation AddAttachment in the csom code.

Reference