Using FileStream in SQL with code first in ASP.NET Core

Question

I need to create a table and use FileStream in that table. In the SQL Server table, I need to use this column:

CREATE TABLE TestTable
(
    FileID  UNIQUEIDENTIFIER NOT NULL ROWGUIDCOL UNIQUE DEFAULT(NEWID()),
    Pic     VARBINARY(MAX) FILESTREAM NULL
)

Now in EF Core code-first how can I create this column?

This is a question about _generating_ the column, right? Not _using_ the column? — gunr2171, Sep 18 '19 at 19:47
Repeating what you said in your post when I ask a clarification question doesn't answer the question. — gunr2171, Sep 18 '19 at 19:49
[This](https://stackoverflow.com/a/6924857/1043380) is an answer from a previous version of EF. I doubt the functionally has changed. — gunr2171, Sep 18 '19 at 19:50

Ryan · Answer 1 · 2019-09-19T05:14:30.230

0

In EF core , you could not use FileStream to save file to database.

Instead, you need to convert the file to byte[](which will convert to varbinary(max) in sql server) and copy the file content over when uploading using a memory-stream for instance.

Model:

public byte[] Picture { get; set; }

Convert file to byte array:

using (var ms = new MemoryStream())
{
  file.CopyTo(ms);
  byte[] fileBytes = ms.ToArray();
  string s = Convert.ToBase64String(fileBytes);
  // act on the Base64 data
}

Refer to

Store files in database using Entity Framework Core

How to convert a file into byte array in memory?

edited Sep 19 '19 at 05:14

answered Sep 19 '19 at 03:31

Ryan

17,241
8
29
43

so from your answer it means that EF Core cannot be used to store a file as a Filestream but instead only as varbinary? – pantonis Jan 24 '20 at 14:12

score 0 · Answer 2 · answered Feb 22 '22 at 18:34

See this solution, in which the author shows how to modify the Up() and Down() methods in an EF migration (i.e. the initial migration) to add a FILESTREAM column, and also how to perform the read/write operations.

He's using EF6, but I would think that the same could be done with EF Core.

Using FileStream in SQL with code first in ASP.NET Core

2 Answers2