ConnectionString未初始化
public static DataTable getRows(string sql)
{
DataSet ds;
SqlConnection con = createCon();
con.Open();
SqlDataAdapter sda = new SqlDataAdapter(sql, con);
ds = new DataSet();
sda.Fill(ds);
con.Close();
return ds.Tables[0];
}
谁能告诉我这个怎么初始化ConnectionString