Question

I’m working on a catalog program and I use this piece of code to find resources on database:

sql = "SELECT * FROM Articoli WHERE CodiceArt='"+CodArtEntry.Text+"' OR Barcode='"+BarcodeEntry.Text+"' OR NomeArt LIKE '%"+NameArtEntry.Text+"%'";

This code works , but if NameArtEntry (GTK# Entry) is empty, it select every record of the database.

How can I avoid that ? Many thanks

Answer 1

Try this

var sql = String.Format("SELECT * FROM Articoli WHERE CodiceArt='{0}' OR Barcode='{1}'", CodArtEntry.Text, BarcodeEntry.Text);
if (!String.IsNullOrWhiteSpace(NameArtEntry.Text))
     sql += String.Format(" OR NomeArt LIKE '%{0}%' ", NameArtEntry.Text);

Using String.Format will make your query more readable, particularly when you write direct sql