c# - Must declare the scalar variable "@photo"? -

i'm trying save image in sql database in image format. error must declare scalar variable @photo when call executenonquery cmd.

using system; using system.io; using system.collections.generic; using system.componentmodel; using system.data; using system.data.oledb; using system.drawing; using system.drawing.imaging; using system.linq; using system.text; using system.windows.forms;  namespace library {     public partial class moviepagemain : form     {         public moviepagemain()         {             initializecomponent();             byte[] photo_aray;         }          private void picmovie_click(object sender, eventargs e)         {             openfiledialog1.title = "select image";             openfiledialog1.showdialog();         }          private void openfiledialog1_fileok(object sender, canceleventargs e)         {             textpic.text = openfiledialog1.filename;             picmovie.image = image.fromfile(textpic.text);         }          private void buttonsave_click(object sender, eventargs e)         {             oledbconnection con = new oledbconnection("provider=sqloledb;user id=sa;password =12345678; initial catalog=library; server=raj; trusted_connection=true;");             oledbcommand cmd = new oledbcommand("insert movie ([title],[genere],[size],[resolution],[frame],[language],[subtitle],[runtime],[imdb],[synopsis],[cast],[director],[date],[picturebox]) values ('" + texttitle.text + "', '" + textgenere.text + "','" + textsize.text + "','" + textres.text + "','" + textframe.text + "','" + textlang.text + "','" + textsub.text + "','" + texttime.text + "','" + textimdb.text + "','" + textsynop.text + "','" + textcast.text + "','" + textdirector.text + "','" + datetimepicker1.value.tostring("mm/dd/yyyy hh:mm").trim() + "',@photo)", con);             conv_photo();             con.open();             int = cmd.executenonquery(); // here exception error accrued // must declare scalar variable "@photo"              messagebox.show("done");         }          void conv_photo()         {             if (picmovie.image != null)             {                 memorystream mst = new memorystream();                 picmovie.image.save(mst, imageformat.jpeg);                 byte[] photo_aray = new byte[mst.length];                 mst.position = 0;                 mst.read(photo_aray, 0, photo_aray.length);                 oledbcommand cmd = new oledbcommand();                 cmd.parameters.addwithvalue("@photo", photo_aray);             }             }     } } 

the issue caused because:

1. you not using correct placeholder parameter inside command text
2. you adding @photo parameter irrelevant oledbcommand object

you have replace @photo ? in command text, i.e. replace + "',@photo)" + "',?)". how specify parameter placeholders oledbcommand.

you should pass cmd object parameter conv_photo():

void conv_photo(oledbcommand cmd) {    if (picmovie.image != null)    {       memorystream mst = new memorystream();       picmovie.image.save(mst, imageformat.jpeg);       byte[] photo_aray = new byte[mst.length];       mst.position = 0;       mst.read(photo_aray, 0, photo_aray.length);       cmd.parameters.addwithvalue("@photo", photo_aray);    }     } 

then invoke conv_photo within buttonsave_click this:

private void buttonsave_click(object sender, eventargs e) {       ...        conv_photo(cmd);       con.open();       int = cmd.executenonquery(); // cmd setup       messagebox.show("done"); }