Issue with dynamically contruct an INSERT statement - using vb code - that uploads a file into a database

Ok, here an issue I'm facing here:

As part of the project requirements I'm working on I need to upload a file to a database tabl, and to dynamically build my INSERT statement that uploads that file using

Here is what I have:

I have a database table called "Attachments", it's design is as follows:

Column (1) Label = "ID"
Column (1) type = PRIMARY KEY
Column (1) Data-Type = "int"

Column (2) Label = "AttachmentContent"
Column (2) type = NORMAL
Column (2) Data-Type = "varbinary(MAX)"

So now, if I want to insert a record into this table, I can do so like this in my VB code:

Dim MC as new MainClass

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See attachment "DB_CLASS.txt" that defines "MainClass"

Now, my issue is with the XXXXXXXXXXXXXXXXXXXXXXX above in my code

I tried to do it this way:

Dim filePath As String = "C:\Some_File.gif"
Dim fs As FileStream = New FileStream(filePath, FileMode.Open, FileAccess.Read)
Dim br As BinaryReader = New BinaryReader(fs)
Dim bytes As Byte() = br.ReadBytes(Convert.ToInt32(fs.Length))
MC.DB("INSERT INTO Attachments (AttachmentContent) VALUES ('"+bytes.toString+"')")

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It gives me an error because the insert statement that the system tries to execute becomes like this at run time:

INSERT INTO Attachments (AttachmentContent) VALUES ('System.Byte[]')

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What am I missing here?
Hussein ZahranAsked:
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Karthik RamachandranCommented:
Try something like this
query = "INSERT INTO student (AttachmentContent) VALUES (@AttachmentContent)"
Using conn as New SqlConnection("connectionStringHere")
    Using comm As New SqlCommand()
        With comm
            .Connection = conn
            .CommandType = CommandType.Text
            .CommandText = query
            .Parameters.AddWithValue("@AttachmentContent", bytes.toString())
        End With
                Catch(ex as SqlException)
                    MessageBox.Show(ex.Message.ToString(), "Error Message")
                End Try
    End Using
End USing

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Hussein ZahranAuthor Commented:
I'm not allowed to execute the SQL statement like this due to some other requirements. Therefore; I mentioned that I need to construct the SQL statement through concatenaiton of strings.

So, all I need is how do I pass the bytes into the "INSERT INTO Attachments (AttachmentContent) VALUES (XXXXXXXXXXXXXXXXXXXXXXX)" string in place of the 'XXXXXXXXXXXXXXXXXXXXXXX'
Hussein ZahranAuthor Commented:
Just to further explain why I can't use the code you're suggesting is that because I don't have access to change the definition of the MainClass.DB method, and that MainClass.DB method is the only way I can read/write from/to a database, and I'm not allowed to create my own method to read/write from/to a database.
Learn SQL Server Core 2016

This course will introduce you to SQL Server Core 2016, as well as teach you about SSMS, data tools, installation, server configuration, using Management Studio, and writing and executing queries.

To get a string out of a byte array, you need to use the correct Encoding object.
If your array contains UTF-8 bytes, you can get the string with:
Dim decodedString = Encoding.UTF8.GetString(bytes)

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Hussein ZahranAuthor Commented:

I tried what you suggested like this:

"INSERT INTO Attachments (AttachmentContent) VALUES (System.Text.Encoding.UTF8.GetString(bytes))"

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it gave me an error, I think my MC.DB() method expects something like this format "0x424D2E30140000.....etc." for the [AttachmentContent] column in Attachments table

Any idea?
Hussein ZahranAuthor Commented:
I got it, the following function converts my "bytes" variable into a hexadec. format:

    Private Function BytesToString(ByVal Input As Byte()) As String
        Dim Result As New System.Text.StringBuilder(Input.Length * 2)
        Dim Part As String
        For Each b As Byte In Input
            Part = Conversion.Hex(b)
            If Part.Length = 1 Then Part = "0" & Part
        Return "0x" + Result.ToString()
    End Function

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It works now

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Hussein ZahranAuthor Commented:
I searched further in the net and I found this solution which now works for me
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