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An Easy Way To Query a Database

4.76/5 (9 votes)
14 Feb 2011CPOL 18.7K  
The following samples should take advantage of using statements and furthermore built in features of the ADO.NET framework. Furthermore, if you open a connection, make sure you open it at the latest time possible and close it as soon as possible.Edit: While I was originally not trying to...
The following samples should take advantage of using statements and furthermore built in features of the ADO.NET framework. Furthermore, if you open a connection, make sure you open it at the latest time possible and close it as soon as possible.

Edit: While I was originally not trying to change too much of the original content, I might as well to incorporate all of the suggestions posted below. As woric and I noticed, the exception handling is generally not a good idea, so it can be removed and handled at a higher level. Though, the using statement should be used to close the connection, so the try/finally isn't necessary. Then, as Fzelle pointed out, the SqlDataAdapter can be passed the connection string and query to simplify that method.

C#
public DataSet select_query(string query, string con_str)
{
  using (SqlDataAdapter da = new SqlDataAdapter(query, con_str))
  {
    DataSet ds = new DataSet();
    da.Fill(ds);  // Automatically opens/closes connection.
    return ds;
  }
}

C#
public int modify_query(string query, global_data data)
{
  using (SqlConnection con = new SqlConnection(data.Con_Str))
  {
    using (SqlCommand comd = new SqlCommand(query, con))
    {
      con.Open();
      int x = comd.ExecuteNonQuery();
      con.Close();
      return x;
    }
  }
}

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)