Mega Code Archive
Use of the WaitAny method of processing multiple asynchronous processes (C#)
<![CDATA[
<%@ Page Language="C#" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<%@ Import Namespace="System.Configuration" %>
<script runat="server">
protected void Page_Load(object sender, EventArgs e)
{
SqlConnection DBCon;
SqlCommand OrdersCommand = new SqlCommand();
SqlCommand CustCommand = new SqlCommand();
SqlDataReader OrdersReader;
SqlDataReader CustReader;
IAsyncResult OrdersASyncResult;
IAsyncResult CustAsyncResult;
int WHIndex;
System.Threading.WaitHandle[] WHandles = new System.Threading.WaitHandle[1];
System.Threading.WaitHandle OrdersWHandle;
System.Threading.WaitHandle CustWHandle;
DBCon = new SqlConnection();
DBCon.ConnectionString = ConfigurationManager.ConnectionStrings["DSN_NorthWind"].ConnectionString;
CustCommand.CommandText = " SELECT * FROM Customers WHERE CompanyName = 'A' ";
CustCommand.CommandType = CommandType.Text;
CustCommand.Connection = DBCon;
OrdersCommand.CommandText =
" SELECT Customers.CompanyName, Customers.ContactName, " +
" Orders.OrderID, Orders.OrderDate, " +
" Orders.RequiredDate, Orders.ShippedDate " +
" FROM Orders, Customers " +
" WHERE Orders.CustomerID = Customers.CustomerID " +
" AND Customers.CompanyName = 'Alfreds Futterkiste' " +
" ORDER BY Customers.CompanyName, Customers.ContactName ";
OrdersCommand.CommandType = CommandType.Text;
OrdersCommand.Connection = DBCon;
DBCon.Open();
CustAsyncResult = CustCommand.BeginExecuteReader();
OrdersASyncResult = OrdersCommand.BeginExecuteReader();
CustWHandle = CustAsyncResult.AsyncWaitHandle;
OrdersWHandle = OrdersASyncResult.AsyncWaitHandle;
WHandles[0] = CustWHandle;
WHandles[1] = OrdersWHandle;
for (int Index = 0; Index < 2; Index++ )
{
WHIndex = System.Threading.WaitHandle.WaitAny(WHandles);
switch (WHIndex)
{
case 0:
CustReader = CustCommand.EndExecuteReader(CustAsyncResult);
gvCustomers.DataSource = CustReader;
gvCustomers.DataBind();
break;
case 1:
OrdersReader =
OrdersCommand.EndExecuteReader(OrdersASyncResult);
gvOrders.DataSource = OrdersReader;
gvOrders.DataBind();
break;
}
}
DBCon.Close();
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>The Wait Any Approach</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:GridView ID="gvCustomers" Width="100%" Runat="server"></asp:GridView>
<br /><br />
<asp:GridView ID="gvOrders" Width="100%" AutoGenerateColumns="False"
Runat="server">
<Columns>
<asp:BoundField HeaderText="Company Name"
DataField="CompanyName"></asp:BoundField>
<asp:BoundField HeaderText="Contact Name"
DataField="ContactName"></asp:BoundField>
<asp:BoundField HeaderText="Order Date" DataField="orderdate"
DataFormatString="{0:d}"></asp:BoundField>
<asp:BoundField HeaderText="Required Date" DataField="requireddate"
DataFormatString="{0:d}"></asp:BoundField>
<asp:BoundField HeaderText="Shipped Date" DataField="shippeddate"
DataFormatString="{0:d}"></asp:BoundField>
</Columns>
</asp:GridView>
</div>
</form>
</body>
</html>
File: Web.config
<configuration>
<connectionStrings>
<add name="DSN_Northwind"
connectionString="Data Source=localhost\SQLEXPRESS;Initial Catalog=Northwind;Integrated Security=True"
providerName="System.Data.SqlClient" />
</connectionStrings>
</configuration>
]]>