Pull Image From Directory and Save To Database as Image Data type

Question

User727214845 posted

Hello,

Please i have images in Directory but i want to pull them and save to my database as Image Data type .

BEGIN TRANSACTION
SET QUOTED_IDENTIFIER ON
SET ARITHABORT ON
SET NUMERIC_ROUNDABORT OFF
SET CONCAT_NULL_YIELDS_NULL ON
SET ANSI_NULLS ON
SET ANSI_PADDING ON
SET ANSI_WARNINGS ON
COMMIT
BEGIN TRANSACTION
GO
CREATE TABLE dbo.Table_1
	(
	Photos image NULL,
	id int NOT NULL IDENTITY (1, 1)
	)  ON [PRIMARY]
	 TEXTIMAGE_ON [PRIMARY]
GO
ALTER TABLE dbo.Table_1 SET (LOCK_ESCALATION = TABLE)
GO
COMMIT

Dim ImageURl As String = "http://localhost/api.sscoe.edu.ng/_photo/7a5942ca-a9f0-49b3-9e34-a9185c631bee.png"
            Dim ImageData As Byte() = Convert.FromBase64String(ImageURl.Replace("data:image/png;base64,", ""))

That is the sample code i have used, when i try saving to database i got an error

he input is not a valid Base-64 string as it contains a non-base 64 character, more than two padding characters, or an illegal character among the padding characters.

Thank you

Answer 1

User-1545767719 posted

by using javascript, obtain a data url string and upload to web service (or equivalent) which can receive the uploaded data url string and convert it to byte array as you do.  you will have to add canvas in the aspx page and draw the image to canvas to obtain data url.

Answer 2

User1535942433 posted

Hi hydar,

 There are two issues for your problem.

1.Your string is not a multiple of 4 long. It needs to be padded to a multiple of 4 using '=' characters.

2.It looks like it's the format of base 64 used for URLs and suchlike, "modified Base64 for URL". This uses - instead of + and _ instead of /.

More details,you could refer to below article:

https://stackoverflow.com/questions/50524665/convert-frombase64string-throws-invalid-base-64-string-error

Best regards,

Yijing Sun

Answer 3

User727214845 posted

Hello,

I solve this issue by using a function that will do the conversion and used the converted image to save to my database, please find below the conversion Function.

 Public Function GetImg(ByVal url As String) As Byte()
        Dim stream As Stream = Nothing
        Dim buf As Byte()

        Try
            Dim myProxy As WebProxy = New WebProxy()
            Dim req As HttpWebRequest = CType(WebRequest.Create(url), HttpWebRequest)
            Dim response As HttpWebResponse = CType(req.GetResponse(), HttpWebResponse)
            stream = response.GetResponseStream()

            Using br As BinaryReader = New BinaryReader(stream)
                Dim len As Integer = CInt((response.ContentLength))
                buf = br.ReadBytes(len)
                br.Close()
            End Using

            stream.Close()
            response.Close()
        Catch exp As Exception
            buf = Nothing
        End Try

        Return (buf)
    End Function

and i call the function:

Dim Image As Byte() = x.GetImg("http://localhost/api.sscoe.edu.ng/_photo/7a5942ca-a9f0-49b3-9e34-a9185c631bee.png")