в 15:31, 26 мая 2010

2010-05-26T15:31:19Z

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2010-05-26T11:42:33Z

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==How to use the InfoMessage event==

<source lang="csharp">
using System;
using System.Data;
using System.Data.SqlClient;
class InfoMessage
{
public static void InfoMessageHandler(object mySender, SqlInfoMessageEventArgs myEvent)
{
Console.WriteLine("The following message was produced:\n" + myEvent.Errors[0]);
}
public static void Main(){
SqlConnection mySqlConnection = new SqlConnection("server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI;");
mySqlConnection.InfoMessage += new SqlInfoMessageEventHandler(InfoMessageHandler);
mySqlConnection.Open();
SqlCommand mySqlCommand = mySqlConnection.CreateCommand();
mySqlCommand.rumandText = "PRINT "This is the message from the PRINT statement"";

mySqlCommand.ExecuteNonQuery();
mySqlCommand.rumandText = "RAISERROR("This is the message from the RAISERROR statement", 10, 1)";

mySqlCommand.ExecuteNonQuery();
mySqlConnection.Close();
}
}

</source>

==How to use the StateChange event==

<source lang="csharp">
using System;
using System.Data;
using System.Data.SqlClient;
class StateChange
{
public static void StateChangeHandler(object mySender, StateChangeEventArgs myEvent)
{
Console.WriteLine("mySqlConnection State has changed from "+myEvent.OriginalState + "to "+myEvent.CurrentState);
}
public static void Main(){
SqlConnection mySqlConnection =new SqlConnection("server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI;");
mySqlConnection.StateChange +=new StateChangeEventHandler(StateChangeHandler);
Console.WriteLine("Calling mySqlConnection.Open()");
mySqlConnection.Open();
Console.WriteLine("Calling mySqlConnection.Close()");
mySqlConnection.Close();
}
}

</source>

==On row updating and updated event==

<source lang="csharp">
using System;
using System.Data;
using System.Data.SqlClient;
class SqlDemo {
static void Main(){
string connString = "server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
SqlConnection cn = new SqlConnection(connString);
try
{
cn.Open();
SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM Employee", cn);

SqlCommandBuilder cb = new SqlCommandBuilder(da);
DataSet ds = new DataSet();
da.Fill(ds, 0, 1, "Employee");
da.RowUpdating += new SqlRowUpdatingEventHandler(OnRowUpdating);
da.RowUpdated += new SqlRowUpdatedEventHandler(OnRowUpdated);
DataTable dt = ds.Tables["Employee"];
dt.Rows[0][1] = "T";
da.Update(ds, "Employee");
da.RowUpdating -= new SqlRowUpdatingEventHandler(OnRowUpdating);
da.RowUpdated -= new SqlRowUpdatedEventHandler(OnRowUpdated);

} catch (SqlException ex) {
Console.WriteLine(ex.Message);
}
finally
{
cn.Close();
}
}

static void OnRowUpdating(object sender, SqlRowUpdatingEventArgs e)
{
Console.WriteLine("OnRowUpdating event");
if (e.Status != UpdateStatus.Continue)
Console.WriteLine("RowStatus = " + e.Status.ToString());
}
static void OnRowUpdated(object sender, SqlRowUpdatedEventArgs e)
{
Console.WriteLine("OnRowUpdating event");
if (e.Status != UpdateStatus.Continue)
Console.WriteLine("RowStatus = " + e.Status.ToString());
}
}

</source>

==Register two SqlConnection change events==

<source lang="csharp">

using System;
using System.Data;
using System.Data.SqlClient;
class SqlDemo {
static void Main(){
string connString = "server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
SqlConnection cn = new SqlConnection(connString);
cn.StateChange += new StateChangeEventHandler(CnStateChange);
cn.StateChange += new StateChangeEventHandler(CnStateChange2);

SqlCommand cmd = new SqlCommand();
cmd.rumandText = "SELECT LastName, FirstName FROM Employee";
cmd.Connection = cn;
try
{
cn.Open();
SqlDataReader dr = cmd.ExecuteReader();
while(dr.Read())
{
Console.WriteLine(dr.GetString(0) + "-" + dr.GetString(1));
}
}
catch(SqlException ex)
{
Console.WriteLine (ex.Message);
}
finally
{
cn.Close();
}
}
static void CnStateChange2(object sender, StateChangeEventArgs ev)
{
Console.WriteLine("------------------------------");
Console.WriteLine("Entering Second Statechange EventHandler");
Console.WriteLine("Sender = " + sender.ToString());
Console.WriteLine("Original State = " + ev.OriginalState.ToString());
Console.WriteLine("Current State = " + ev.CurrentState.ToString());
Console.WriteLine("Exiting Second StateChange EventHandler");
Console.WriteLine("------------------------------");
}

static void CnStateChange(object sender, StateChangeEventArgs ev)
{
Console.WriteLine("------------------------------");
Console.WriteLine("Entering StateChange EventHandler");
Console.WriteLine("Sender = "+ sender.ToString());
Console.WriteLine("Original State = "+ ev.OriginalState.ToString());
Console.WriteLine("Current State = "+ ev.CurrentState.ToString());
Console.WriteLine("Exiting StateChange EventHandler");
Console.WriteLine("------------------------------");
}
}

</source>

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в 15:31, 26 мая 2010

Admin: 1 версия