в 15:30, 26 мая 2010

2010-05-26T15:30:57Z

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2010-05-26T11:56:42Z

1 версия

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== Executes a database asynchronously but uses code to poll the operation for completion.==



<source lang="csharp">
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs"
Inherits="Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Polling for Completion</title>
</head>
<body>

<div id="pageContent">
<form id="form1" runat="server">
<asp:Button ID="Button1" runat="server" Text="Execute the command" OnClick="Button1_Click" />
<hr />
<asp:Label ID="Results" runat="server"></asp:Label>
</form>
</div>
</body>
</html>

File: Default.aspx.cs
using System;
using System.Data;
using System.Configuration;
using System.Data.SqlClient;
using System.Web;
using System.Text;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class Default : System.Web.UI.Page
{
protected void Button1_Click(object sender, EventArgs e)
{
string connString = "Async=true;SERVER=(local);DATABASE=northwind;Trusted_Connection=yes;";
using (SqlConnection conn = new SqlConnection(connString))
{
SqlCommand cmd = new SqlCommand("SELECT lastname,firstname FROM employees", conn);
conn.Open();
IAsyncResult iar = cmd.BeginExecuteReader();
do {
} while (!iar.IsCompleted);
SqlDataReader reader = cmd.EndExecuteReader(iar);
ProcessData(reader);
}
}
protected void ProcessData(SqlDataReader reader)
{
StringBuilder sb = new StringBuilder("");
while (reader.Read())
sb.AppendFormat("{0}, {1}<br/>", reader[0], reader[1]);
reader.Close();
Results.Text = sb.ToString();
}
}</source>

== Fire a database asynchronous operation and then proceeds up to the point where results are required==



<source lang="csharp">
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs"
Inherits="Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Non-blocking Commands</title>
</head>
<body>
<div id="pageContent">
<form id="form1" runat="server">
<asp:Button ID="Button1" runat="server" Text="Execute the command" OnClick="Button1_Click" />
<hr />
<asp:Label ID="Results" runat="server"></asp:Label>
</form>
</div>
</body>
</html>
File: Default.aspx.cs
using System;
using System.Data;
using System.Configuration;
using System.Data.SqlClient;
using System.Web;
using System.Text;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class Default : System.Web.UI.Page
{
protected void Button1_Click(object sender, EventArgs e)
{
string connString = "Async=true;SERVER=(local);DATABASE=northwind;Trusted_Connection=yes;";
using (SqlConnection conn = new SqlConnection(connString))
{
SqlCommand cmd = new SqlCommand("SELECT lastname,firstname FROM employees", conn);
conn.Open();
IAsyncResult iar = cmd.BeginExecuteReader();
SqlDataReader reader = (SqlDataReader) cmd.EndExecuteReader(iar);
ProcessData(reader);
}
}
protected void ProcessData(SqlDataReader reader)
{
StringBuilder sb = new StringBuilder("");
while (reader.Read())
sb.AppendFormat("{0}, {1}<br/>", reader[0], reader[1]);
reader.Close();
Results.Text = sb.ToString();
}
}</source>

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ASP.NET Tutorial/ADO.net Database/Async - История изменений

в 15:30, 26 мая 2010

Admin: 1 версия