Csharp/CSharp Tutorial/ADO.Net/OleDbConnection — различия между версиями
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Текущая версия на 15:19, 26 мая 2010
Содержание
- 1 Connecting to an OLE DB Data Source
- 2 Connection for OleDb
- 3 Connection Pooling Sample
- 4 Connect to SqlServer using OleDbConnection
- 5 OleDbConnection connection state
- 6 Output properties for OleDbConnection
- 7 Reading Access Data with OleDbConnection
- 8 Retrieves a list of tables in a database
- 9 Retrieving Data from a Text File
Connecting to an OLE DB Data Source
<source lang="csharp">using System; using System.Data.OleDb;
class Program { static void Main(string[] args) { string oledbConnectString = "Provider=SQLOLEDB;Data Source=(local);" + "Initial Catalog=AdventureWorks;Integrated Security=SSPI"; string sqlSelect = "SELECT TOP 5 Title, FirstName, LastName FROM Person.Contact"; using (OleDbConnection connection =new OleDbConnection(oledbConnectString)) { OleDbCommand command = new OleDbCommand(sqlSelect, connection); connection.Open( ); OleDbDataReader reader = command.ExecuteReader( ); while (reader.Read( )) Console.WriteLine("{0} {1}", reader[0], reader[1]); } } }</source>
Connection for OleDb
<source lang="csharp">using System; using System.Data; using System.Data.OleDb;
class ConnectionOleDb { static void Main() { OleDbConnection conn = new OleDbConnection(@"provider = sqloledb;data source = .\sqlexpress;integrated security = sspi;"); try { conn.Open(); Console.WriteLine("\tConnection String: {0}",conn.ConnectionString); Console.WriteLine("\tDatabase: {0}",conn.Database); Console.WriteLine("\tDataSource: {0}",conn.DataSource); Console.WriteLine("\tServerVersion: {0}",conn.ServerVersion); Console.WriteLine("\tState: {0}",conn.State); } catch (OleDbException e) { Console.WriteLine("Error: " + e); } finally { conn.Close(); Console.WriteLine("Connection closed."); } } }</source>
Connection Pooling Sample
<source lang="csharp">using System; using System.Data; using System.Data.SqlClient; using System.Data.OleDb; class MainClass {
static void Main(string[] args) { string ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0; Data Source=c:\Northwind.mdb"; OleDbConnection conn = new OleDbConnection(ConnectionString); conn.Open(); conn.Close(); OleDbConnection.ReleaseObjectPool(); }
}</source>
Connect to SqlServer using OleDbConnection
<source lang="csharp">using System; using System.Data.SqlClient; using System.Data.OleDb; using System.Data.Odbc;
class Program { static void Main(string[] args) { string oledbConnectString = "Provider=SQLOLEDB;Data Source=(local);Initial Catalog=AdventureWorks;User Id=sa;Password=password;"; using (OleDbConnection connection = new OleDbConnection(oledbConnectString)) { connection.Open( ); Console.WriteLine("ConnectionString = {0}\n", oledbConnectString); Console.WriteLine("State = {0}", connection.State); Console.WriteLine("DataSource = {0}", connection.DataSource); Console.WriteLine("ServerVersion = {0}", connection.ServerVersion); } } }</source>
OleDbConnection connection state
<source lang="csharp">using System; using System.Data; using System.Data.SqlClient; using System.Data.OleDb; class MainClass {
public static void Main() { using (OleDbConnection con = new OleDbConnection()) { con.ConnectionString ="provider=sqloledb;server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI"; con.Open(); if (con.State == ConnectionState.Open) { Console.WriteLine("OleDbConnection Information:"); Console.WriteLine(" Connection State = " + con.State); Console.WriteLine(" Connection String = " + con.ConnectionString); Console.WriteLine(" Database Source = " + con.DataSource); Console.WriteLine(" Database = " + con.Database); Console.WriteLine(" Server Version = " + con.ServerVersion); Console.WriteLine(" Timeout = " + con.ConnectionTimeout); } else { Console.WriteLine("OleDbConnection failed to open."); Console.WriteLine(" Connection State = " + con.State); } } }
}</source>
OleDbConnection Information: Connection State = Open Connection String = provider=sqloledb;server=(local)\SQLEXPRESS;database=MyDatabase;Integrated Sec urity=SSPI Database Source = (local)\SQLEXPRESS Database = MyDatabase Server Version = 09.00.1399 Timeout = 15
Output properties for OleDbConnection
<source lang="csharp">using System; using System.Drawing; using System.Collections; using System.ruponentModel; using System.Windows.Forms; using System.Data; using System.Data.OleDb; using System.Data.SqlClient;
public class MainClass{
static void Main() { string ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0; Data Source=c:\Northwind.mdb"; OleDbConnection conn = new OleDbConnection(ConnectionString); // Open the connection if( conn.State != ConnectionState.Open) conn.Open(); // Show the connection properties Console.WriteLine( "Connection String :"+conn.ConnectionString +", DataSource :"+ conn.DataSource.ToString() +", Provider :"+ conn.Provider.ToString() +", Server Version:"+ conn.ServerVersion.ToString() +", Connection Time Out:"+ conn.ConnectionTimeout.ToString() ); // Close the connection if( conn.State == ConnectionState.Open) conn.Close(); }
}</source>
Connection String :Provider=Microsoft.Jet.OLEDB.4.0; Data Source=c:\Northwind.mdb, DataSource :c:\No rthwind.mdb, Provider :Microsoft.Jet.OLEDB.4.0, Server Version:04.00.0000, Connection Time Out:15
Reading Access Data with OleDbConnection
<source lang="csharp">using System; using System.Data; using System.Data.OleDb; using System.Collections.Generic; using System.Text;
class Program{ static void Main(string[] args){ OleDbConnection thisConnection = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=nwind.mdb"); thisConnection.Open(); OleDbCommand thisCommand = thisConnection.CreateCommand(); thisCommand.rumandText = "SELECT CustomerID, CompanyName FROM Customers"; OleDbDataReader thisReader = thisCommand.ExecuteReader(); while (thisReader.Read()){ Console.WriteLine("\t{0}\t{1}", thisReader["CustomerID"], thisReader["CompanyName"]); } thisReader.Close(); thisConnection.Close(); } }</source>
Retrieves a list of tables in a database
<source lang="csharp">using System; using System.Data; using System.Data.OleDb; public class GetSchema {
public static void Main() { string connectionString = "Data Source=localhost;Provider=SQLOLEDB;Initial Catalog=Northwind;Integrated Security=SSPI"; OleDbConnection con = new OleDbConnection(connectionString); DataTable schema; con.Open(); schema = con.GetOleDbSchemaTable(OleDbSchemaGuid.Tables,new object[] {null, null, null, null}); con.Close(); foreach (DataRow row in schema.Rows){ Console.WriteLine(row["TABLE_TYPE"] + ": " + row["TABLE_NAME"]); } }
}</source>
Retrieving Data from a Text File
<source lang="csharp">using System; using System.Data; using System.Data.OleDb;
class Program { static void Main(string[] args) { string sqlSelect = "SELECT * FROM [Category.txt]"; string connectString = "Provider=Microsoft.ACE.OLEDB.12.0;" + @"Data Source=..\;" + "Extended Properties=\"text;HDR=yes;FMT=Delimited\";"; OleDbDataAdapter da = new OleDbDataAdapter(sqlSelect, connectString); DataTable dt = new DataTable("Categories"); da.Fill(dt); foreach (DataRow row in dt.Rows) { Console.WriteLine("{0}; {1}; {2}", row["CategoryID"], row["CategoryName"], row["Description"]); } } }</source>