c# - Retrieve Images from sql server database Error -


i storing images database on table called test contain (id,name,image), when try retrieve images using code :

sqlconnection cn = new sqlconnection(constring); sqlcommand cmd = new sqlcommand("select * test id ='"+txtid.text+"'", cn); sqldatareader myreader; try {     cn.open();      myreader = cmd.executereader();     if (myreader.hasrows)     {         txtid.text = myreader[0].tostring();         txtname.text = myreader[1].tostring();         byte[] img = (byte[])(myreader[2]);         if (img == null)             picturebox1.image = null;         else         {             memorystream ms = new memorystream(img);             picturebox1.image = image.fromstream(ms);         }     }     else     {         messagebox.show("do not found");     }      cn.close(); } catch (exception ex) { messagebox.show(ex.message); }

i have error : invalid attempt read when no data present.

hasrows determines whether there rows. need read() reader advance.

something should work (assuming want 1 row).

myreader = cmd.executereader(); if (myreader.read()) { ...

also sure parameterize sql select - @ moment vulnerable sql injection attacks, , dispose of things memorystream , datareader


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