Retrieve and save an image

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I have an Image type column in MSSQL database named photo. The name of database is also photo (I know thats bad).
I want to get this image and store it back in some other record.
Here is my code:
b.com.CommandText = "SELECT photo from photo WHERE model=@model";
b.com.Parameters.Add("@model", txt_model.Text.Trim());
if (b.con.State == ConnectionState.Closed)
b.con.Open();
b.dr = b.com.ExecuteReader();
if (b.dr.HasRows)
{
b.dr.Read();
b.com.Parameters.Add("@j", b.dr.GetValue(0));
b.dr.Close();
}

Here is my exception thrown by ExecuteScalar() when I tried to insert this image again.

C#

Unable to cast object of type 'System.Byte[]' to type 'System.IConvertible'.

What I have tried:

Here is my code:
b.com.CommandText = "SELECT photo from photo WHERE model=@model";
b.com.Parameters.Add("@model", txt_model.Text.Trim());
if (b.con.State == ConnectionState.Closed)
b.con.Open();
b.dr = b.com.ExecuteReader();
if (b.dr.HasRows)
{
b.dr.Read();
b.com.Parameters.Add("@j", b.dr.GetValue(0));
b.dr.Close();
}

Here is my exception thrown by ExecuteScalar() when I tried to insert this image again.

C#

Unable to cast object of type 'System.Byte[]' to type 'System.IConvertible'.

Posted 10-Jun-16 1:10am

Member 8057273

Updated 10-Jun-16 1:27am

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OriginalGriff · Answer 1 · 2016-06-10T01:27:00

Probably, the query you don't show that throws the error is trying to return an image as it's scalar value - at which point you would get that error.
Without the actual code around the ExecuteScalar and the actual SQL it's impossible to tell, but they chances are that you are trying to do something like:

C#

int i = (int) cmd.ExecuteScalar();

Which you can't do with a byte array.
Have a look at this: Why do I get a "Parameter is not valid." exception when I read an image from my database?[^] which gives the code I use.