Why Can't I Get the Scoped Identity From EF After a Record is Saved?

Question

I have this code that successfully creates a new entry in my Posts table but for some reason the Postid is null even though I don't try to access it until after the new record is created. public async Task OnPostAsync() { if (!ModelState.IsValid) { return Page(); } _context.Posts. Add (Posts); await _context.SaveChangesAsync(); int postid = Posts.Postid; string targeturl = linkgenerator.postlink(Posts.Postid, Posts.Title); return RedirectToPage(targeturl); } According to this tutorial all I need to do to access a newly created primary key is to type the name of the table followed by a "." and the name of the column https://www.entityframeworktutorial.net/faq/how-to-get-id-of-saved-entity-in-entity-framework.aspx but the above code returns a null value instead of the newly created Postid. Most of the new record is created using a form on a Razor Page. The above code is from code behind on that page. After checking the database I can confirm that the new record is in fact created. Please word any response in a way that someone familiar with WebForms and not familiar at all with MVC can understand. I chose to convert my WebForms site to a .Net Core Razor Pages site because I was given the impression that it is closer to WebForms than any other modern option that uses the .Net Framework. So far it seems nothing like WebForms. Am I at least correct in believing that the OnPostAsync event in a Razor Page is the equivalent of the FormView_ItemInserting event in a WebForm? UPDATE: Looking back it appears that I was never able to use the new primary key value in my WebForm until the SqlDataSource1_Inserted event. Is it possible to get the primary key during the same event on a Razor Page or do I need to add a second task that runs after the first one?

Sachin Singh · Answer

At first correct your naming convention. let DBSet as Posts and your object as Post your code should look like public async Task OnPostAsync() { if (!ModelState.IsValid) { return Page(); } _context.Posts.Add(Post); await _context.SaveChangesAsync(); int postid = Post.Postid; string targeturl = linkgenerator.postlink(Post.Postid, Post.Title); return RedirectToPage(targeturl); } Second , you misunderstood that you will get recently created entity's Id by TableName.Id , No rather you after adding the object into DbSet collection Like _Context.Posts.Add(PostObj) , when you save changes on database by _Context.SaveChanges(); you can get the Id of that object only by PostObj.Postid So , instead of table name use object name , obviously you can add a single object of Post type into the collection Posts and that object will give you its Id after successful save.