O365 - CSOM upload 2MB files

uploadfile.cs

var spContext = SharePointContextProvider.Current.GetSharePointContext(HttpContext, SPHostUrl);

using (var clientContext = spContext.CreateUserClientContextForSPAppWeb())
{
    if (clientContext != null)
    {
        //code for file size < 2MB
        //file is the input which we uploaded. It can be taken from Request.Files
        FileCreationInformation newFile = new FileCreationInformation();
        newFile.Content = System.IO.File.ReadAllBytes(file.FileName);
        newFile.Url = Path.GetFileName(file.FileName);

        List docs = clientContext.Web.Lists.GetByTitle("List_Name");
        Microsoft.SharePoint.Client.File uploadFile = docs.RootFolder.Files.Add(newFile);
        clientContext.Load(uploadFile);
        clientContext.ExecuteQuery();
    }
}