parameterscommand.cs

Csharp实例编程百例.rar

using System;
using System.Data;             
using System.Data.OleDb;  
namespace ParametersCommandApp
{
	class ParametersCommand
	{
		static void Main() 
		{
			OleDbConnection connection = new OleDbConnection
				(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=E:\C#Program\C#100\Chapter3\NWIND.mdb");
			// create OleDbCommand objects
			OleDbCommand nonqueryCommand = connection.CreateCommand();

			try 
			{
				// open connection
				connection.Open();

				// execute non-query to create temporary table
				nonqueryCommand.CommandText = 
                  "CREATE TABLE MyTempTable(Name VARCHAR(30),TestNumber integer)";
				Console.WriteLine(nonqueryCommand.CommandText);
				nonqueryCommand.ExecuteNonQuery();

				// create INSERT command with named parameters
				nonqueryCommand.CommandText = 
					"INSERT INTO MyTempTable VALUES (@Name, @Number)" ;

				// add parameters to Command object Parameters collection
				nonqueryCommand.Parameters.Add("@Name", OleDbType.VarChar, 30);
				nonqueryCommand.Parameters.Add("@Number", OleDbType.Integer);
				
				// prepare INSERT command for repeated execution
				nonqueryCommand.Prepare();
				
				// data to be inserted
				string[] names = { "Enrico", "Franco", "Gloria", "Horace" } ;
				int i;
				for (i=1; i<=4; i++)
				{
					nonqueryCommand.Parameters["@Name"].Value = names[i-1];
					nonqueryCommand.Parameters["@Number"].Value = i;
					Console.WriteLine(nonqueryCommand.CommandText);
					Console.WriteLine("Number of Rows Affected is: {0}",
						nonqueryCommand.ExecuteNonQuery() );
				}
			} 
			catch (OleDbException ex) 
			{
				Console.WriteLine(ex.ToString());
			}
			finally 
			{  
				connection.Close();  // close connection
				Console.WriteLine("Connection Closed.");
			}
		}
	}
}