Today, in this article lets dig out some theory stuff first and later we will
try to implement the studied concepts i: e Per Single based Instance Management
using WCF.
Based on My Earlier Articles
Per Call Based - Instance Management in WCF:
http://www.c-sharpcorner.com/UploadFile/54db21/per-call-based-instance-management-in-wcf-hosted-on-web-ap/
Per Session Based - Instance Management in WCF:
http://www.c-sharpcorner.com/UploadFile/54db21/per-session-based-instance-management-in-wcf-hosted-on-web/
Let's also try this good concept eventually.
In the meanwhile I will take very less time in letting you know the main key
differences in tabular format. Which is described as below
|
S.No
|
Per-Call
Based |
Per
Session- Based |
Single
Instance Based |
|
1 |
New Service
Instance will be created for every client request. In Simple terms
"Single Client but Many Instances".
|
For Every
Client New Service Instance will be created. It Simple terms
"Dedicated Instance for Client" or "Each Client has allocated
independent instance".
|
Here the
entire clients are interacted in very rigid fashion as they will be
communicating with single service instance.
In Simple
terms "Many Clients but Single Instance".
|
|
2 |
Instance
will be disposed or discharged only after the response is reverted back
to client. In Simple terms" Deliver the Content and die"
|
Instance
will be disposed or discharged only after the response is reverted back
to client. In Simple terms" Deliver the Content and die"
|
But, Here
What happens exactly is the instance is disposed or deleted when the
client is destroyed. I mean in Simple term "Service Instance will be
there forever until and unless client is destroyed".
|
Question Arises: What is Instance Management?
We can say it is a type of rules governed to manage the services with clients.
It provides high end in scalability, durability and effective transaction
management.
Question Arises: What is Per-Single Based Instance Management?
Key Point Here To Remember
-
Basically we can term it as "SHARED SERVICE" because scenario behind this all
the clients calls are divergently connected to single instance and itself says
half of the hints like its singleton. I mean to say in simple terms "Single
Instance is generated only once and lives lifelong and longer. It is generated
when the host is created."
-
The Client does not needs sessions because singleton instance will generate a
session ID for the client.
-
The main reason to go and opt for singleton instance management is you can
provide valuable and effective stateful interaction across multiple clients
deployed
Let's Now Try and Dig for Some Disadvantages or Demerits as well
-
When the request calls are more from the client the singleton instance which
will be assisting towards request will be served with multiple threads. But
though provide response simultaneously at some point of peek time the
concurrency will be lost and throughput is genuinely lower with less
availability to the client
-
Avoiding it would be much better unless you have got multiple clients who
want to have shared stateful resource.
So, let's try to implement this concept so that we can get much better idea on
this:
So, firstly we will create simple method in IService1, Where the Complete Code
of IService1.cs looks like this:
using
System;
using
System.ServiceModel;
namespace
SimpleInstanceManagement
{
// NOTE: You can use the "Rename" command on the "Refactor"
menu to change the class name "Service1" in code, svc and config file together.
[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
public class
Service1 : IService1,
IDisposable
{
public int
Heighter = 0; public
int SimpleMethod(int a)
{
a = (Heighter = Heighter + 1); return
a;
}
public void
Dispose()
{
Heighter = Heighter - 1;
}
}
}
The Complete Code of Service1.svc looks like this:
using
System.ServiceModel;
namespace
SimpleInstanceManagement
{
// NOTE: You can use the "Rename" command on the "Refactor"
menu to change the interface name "IService1" in both code and config file
together.
[ServiceContract]
public interface
IService1
{
[OperationContract]
int SimpleMethod(int
a);
}
}
The Complete Code of Web.Config looks like this:
<?xml version="1.0"?>
<configuration>
<system.web>
<compilation debug="true" targetFramework="4.0" />
</system.web>
<system.serviceModel>
<behaviors>
<serviceBehaviors>
<behavior name="Application">
<!-- To avoid disclosing
metadata information, set the value below to false and remove the metadata
endpoint above before deployment -->
<serviceMetadata
httpGetEnabled="true"/>
<!-- To receive exception
details in faults for debugging purposes, set the value below to true. Set to
false before deployment to avoid disclosing exception information -->
<serviceDebug
includeExceptionDetailInFaults="false"/>
</behavior>
</serviceBehaviors>
</behaviors>
<serviceHostingEnvironment multipleSiteBindingsEnabled="true"
/>
<services>
<service name="SimpleInstanceManagement.Service1"
behaviorConfiguration="Application">
<endpoint address="/SimpleAddress"
binding="wsHttpBinding" contract="SimpleInstanceManagement.IService1">
</endpoint>
<endpoint address="mex" binding="mexHttpBinding"
contract="IMetadataExchange">
</endpoint>
<host>
<baseAddresses>
<add
baseAddress="http://localhost:49257/Service1.svc"/>
</baseAddresses>
</host>
</service>
</services>
</system.serviceModel>
<system.webServer>
<modules runAllManagedModulesForAllRequests="true"/>
</system.webServer>
</configuration> |
I have created New Web Application where I have added it to existing solution
files. I have specified service reference with a link as given below:
http://localhost:49257/Service1.svc
The Complete Code of WebForm1.aspx looks like this:
<%@
Page Language="C#"
AutoEventWireup="true"
CodeBehind="WebForm1.aspx.cs"
Inherits="Instance.WebForm1"
%>
<!DOCTYPE
html PUBLIC
"-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html
xmlns="http://www.w3.org/1999/xhtml">
<head
id="Head1" runat="server">
<title></title>
</head>
<body>
<form
id="form1"
runat="server">
<div>
<center>
<table>
<tr>
<td>
<asp:Label
ID="Label1"
runat="server"
Text="Please Enter Some
Value" ForeColor="Brown"
Font-Bold="
true" Font-Italic="true"></asp:Label>
</td>
<td>
<asp:TextBox
ID="TextBox1"
runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td>
</td>
<td>
<asp:Button
ID="Button1"
runat="server"
Text="Click Here"
OnClick="Button1Click"
Style="margin-left:
0px" Width="118px"
/>
</td>
</tr>
</table>
</center>
</div>
</form>
</body>
</html>
The Complete Code of WebForm1.aspx.cs looks like this:
using
System;
using
Instance.ServiceReference1;
namespace
Instance
{
public partial
class WebForm1
: System.Web.UI.Page
{
protected void
PageLoad(object sender,
EventArgs e)
{
}
protected void
Button1Click(object sender,
EventArgs e)
{
if (TextBox1.Text !=
null)
if ((TextBox1.Text) ==
"1")
{
var ab =
new Service1Client();
Response.Write("<center>The
Value is: <b>" + ab.SimpleMethod((Convert.ToInt32(TextBox1.Text)))
+
"</br></b></center>");
Response.Write("<center>The
Value is: <b>" + ab.SimpleMethod((Convert.ToInt32(TextBox1.Text)))
+
"</br></b></center>");
Response.Write("<center>The
Value is: <b>" + ab.SimpleMethod((Convert.ToInt32(TextBox1.Text)))
+
"</br></b></center>");
Response.Write("<center><i>Second Instance Created
for Service</i></center>");
var bc =
new Service1Client();
Response.Write("<center>The
Value is: <b>" + bc.SimpleMethod(Convert.ToInt32(TextBox1.Text))
+
"</br></b></center>");
Response.Write("<center>The
Value is: <b>" + bc.SimpleMethod(Convert.ToInt32(TextBox1.Text))
+
"</br></b></center>");
Response.Write("<center>The
Value is: <b>" + bc.SimpleMethod((Convert.ToInt32(TextBox1.Text)))
+
"</br></b></center>");
Response.Write("<center>The
Value is: <b>" + bc.SimpleMethod((Convert.ToInt32(TextBox1.Text)))
+
"</br></b></center>");
}
else
{
Response.Write("<center><b><i>Please
Enter Some Values or Enter Correct Values</i></b></center>");
}
}
}
}
The Output of the application looks like this:
![Per Single Output.png]()
The Output of the application if entered wrong or null:
![Per Single Output Error.png]()
I hope this article is useful for you.