InProc Session State Mode in ASP.Net

<configuration>
  <system.web>
    <sessionState mode="InProc" timeout="25"></sessionState>
  </system.web>
</configuration>

This website is created in the "C:\inetpub\wwwroot\InProcSessionExample" location because this site is on IIS.

Figure 3. Website on IIS

Step 3. Start Web Site on IIS.

Right-click on "Default Web Site" then go to "Manage Web Site" then click on "Start".

Figure 4. Start web site on IIS

Step 4. Store Session Data.

Now create a web page that stores data in a session variable. I create a web form "User. aspx" that has one TextBox control for the user name input and one button control that stores the user name in a session variable after a click. The following code snippet is for "User. aspx".

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="User.aspx.cs" Inherits="User" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
        <div>
            Name : <asp:TextBox ID="txtName" runat="server"></asp:TextBox><br />
            <asp:Button ID="btnSubmit" runat="server" Text="Submit" OnClick="btnSubmit_Click" />
        </div>
    </form>
</body>
</html>

Now provide the following code in the button click event to store the user name in a session variable in the code behind the file ("User.aspx.cs") and redirect to another page to show the session data. The following is the code snippet for it.

using System;

public partial class User : System.Web.UI.Page
{
    protected void btnSubmit_Click(object sender, EventArgs e)
    {
        Session["Name"] = txtName.Text;
        Response.Redirect("UserDetail.aspx");
    }
}

Step 5. Retrieve Session Data.

To retrieve session data I create another web page "UserDetail.aspx" and its code behind the page, the Page_Load() event has code to retrieve the session data. As in the following code snippet if the session data exists then the try block is successfully executed otherwise the catch block will be executed.

using System;

public partial class UserDetail : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        try
        {
            string name = Session["Name"].ToString();
            Response.Write(string.Format("User name is : {0}", name));
        }
        catch (NullReferenceException ex)
        {
            Response.Write(ex.Message + " Becasue Session doesn't exist");
        }
    }
}

Step 6. Run the application

You fill in the user name in the "Name" input field then click on the "Submit" button. Then you get the result from your first page of input data that is successfully shown on another page. Let's see that in Figure 1.5.

Figure 5. Output of application

Now reset IIS means run "iisreset" command.

Figure 6. IIS reset

Now refresh the page where the session data is shown, the UserDetail.aspx page and you will see that now the catch block code will be executed because the session data is stored on the server so that data is lost by server reset.

Figure 7. Session data lost on server reset

Advantages of InProc Session state mode

Here is a list of the advantages of the InProc Session State Mode.

1. It is easy to implement.
2. It stores the session data on the server so it is fast.
3. In this mode, it is not necessary to serialize and de-serialize to store and retrieve data in the session variables.

Disadvantages of InProc Session state mode

Here is a list of the disadvantages of the InProc Session State Mode.

1. When the application domain or worker process recycles, the session data will be lost.
2. It is usually the fastest, but more session data means more memory is used on the web server, and that can affect performance
3. It won't work in web farm scenarios and web garden scenarios, because in these scenarios multiple "aspnet_wp.exe" processes will be running on the same machine.

Conclusion

The InProc Session State Mode is a very fast session storing mechanism but suitable only for small web applications. InProc session data would be lost if we restart the server or if the application domain is recycled.