我对C#很新.我正在尝试使用以下方法检索列数: SELECT count(*) FROM sys.columns 您能解释一下如何使用该命令并将其放入变量中. string connectionString = "Data Source=(local);Initial Catalog=Northwind;" + "
SELECT count(*) FROM sys.columns
您能解释一下如何使用该命令并将其放入变量中.
string connectionString = "Data Source=(local);Initial Catalog=Northwind;" + "Integrated Security=true"; // Provide the query string with a parameter placeholder. string queryString = "SELECT Count(*) from sys.columns"; // Specify the parameter value. int paramValue = 5; // Create and open the connection in a using block. This // ensures that all resources will be closed and disposed // when the code exits. using (SqlConnection connection = new SqlConnection(connectionString)) { // Create the Command and Parameter objects. SqlCommand command = new SqlCommand(queryString, connection); // Open the connection in a try/catch block. // Create and execute the DataReader, writing the result // set to the console window. try { connection.Open(); SqlDataReader reader = command.ExecuteReader(); while (reader.Read()) { Console.WriteLine("\t{0}", reader[0]); } reader.Close(); } catch (Exception ex) { Console.WriteLine(ex.Message); } Console.ReadLine(); }