.NET,
AJAX,
ASP.NET Dynamic Data,
C#,
CSS,
Database,
LINQ,
MVC,
Page Output Caching,
SQL Server,
VB.NET,
WCF,
WPF,
XML
Before starting Page Output caching we need to know the compilation process of a page, because based on the generation of page we should able to understand why should we used caching . ASPX Page compiled in two stage process. First, the code is compiled into the Microsoft Intermediate Language (MSIL). Then, the MSIL is compiled into native code (by JIT Compiler ) during execution. and entire code in an ASP.NET Web page is compiled into MSIL when we built the sites , but at the time of execution only the portion of MSIL Converted to native code which is need by user or user request, which also improve performance.
Now what ever we are getting , if there is some page which change frequently JIT need compile every time. So, We can use Page output for those page which content are relatively static. So rather than generating the page on each user request we can cached the page using Page output caching so that it can be access from cache itself. so, Instead of pages can be generated once and then cached for subsequent fetches.Page output caching allows the entire content of a given page to be stored in the cache.
The first request is generated page is been cached and for same page request page should be retrieve from cache itself rather that regenerating the page.
For Output caching , OutputCache directive can be added to any ASP.NET page, specifying the duration (in seconds) that the page should be cached. The code.
<%@ Page Language="C#" %>
<%@ OutputCache Duration='300' VaryByParam='none' %>
<html>
<script runat="server">
protected void Page_Load(Object sender, EventArgs e) {
lbl_msg.Text = DateTime.Now.ToString();
}
</script>
<body>
<h3>Output Cache example</h3>
<p>Page generated on:
<asp:label id="lbl_msg" runat="server"/></p>
</body>
</html>
void Page_Load(Object sender, EventArgs e) {
Response.Cache.SetExpires(DateTime.Now.AddSeconds(360));
Response.Cache.SetCacheability(
HttpCacheability.Public);
Response.Cache.SetSlidingExpiration(true);
_msg.Text = DateTime.Now.ToString();
}
<%@ OutputCache Duration="40" VaryByParam="*" %>
All the attributes that we specify in an OutputCache directive are used to populate an instance of the System.Web.HttpCachePolicy class by calling. The complete implementation of cache policies provided by ASP.NET is encapsulated in the HttpCachePolicy class. Following is the another implementation of caching from code behind.
Output Caching Location:
As I have already mention We can store cached data in different location like client, server or in between client and server , Now I am going to discuss how this is feasible to set location of cached data. If we store the cached data it save the page rendering time by fetching the data from catch. There is another way that we can save cached data on client browser , which reduce the network traffic. OutputCache directive on a page enables all three types of caching—server, client, and proxy—by default.
Following Table shown you the Location details . It show the location of cached and what should be the effects on Cache-Control and Expires Header.
For example, if you specified a value of 'Client' for the Location attribute of an OutputCache directive on a page, the page would not be saved in the server cache, but the response would include a Cache-Control header ( Pages can indicate whether they should be cached on a proxy by using the Cache-Control header.) value of private and an Expires header (HTTP response, indicating the date and time after which the page should be retrieved from the server again ) with a timestamp set to the time indicated by the Duration attribute
<%@ OutputCache Duration='120' Location='Client' VaryByParam='none' %>
This would save the cached for 120 second and cached data should not be saved on Server it should store only on client browser.
Now what ever we are getting , if there is some page which change frequently JIT need compile every time. So, We can use Page output for those page which content are relatively static. So rather than generating the page on each user request we can cached the page using Page output caching so that it can be access from cache itself. so, Instead of pages can be generated once and then cached for subsequent fetches.Page output caching allows the entire content of a given page to be stored in the cache.
The first request is generated page is been cached and for same page request page should be retrieve from cache itself rather that regenerating the page.
For Output caching , OutputCache directive can be added to any ASP.NET page, specifying the duration (in seconds) that the page should be cached. The code.
<%@ Page Language="C#" %>
<%@ OutputCache Duration='300' VaryByParam='none' %>
<html>
<script runat="server">
protected void Page_Load(Object sender, EventArgs e) {
lbl_msg.Text = DateTime.Now.ToString();
}
</script>
<body>
<h3>Output Cache example</h3>
<p>Page generated on:
<asp:label id="lbl_msg" runat="server"/></p>
</body>
</html>
void Page_Load(Object sender, EventArgs e) {
Response.Cache.SetExpires(DateTime.Now.AddSeconds(360));
Response.Cache.SetCacheability(
HttpCacheability.Public);
Response.Cache.SetSlidingExpiration(true);
_msg.Text = DateTime.Now.ToString();
}
<%@ OutputCache Duration="40" VaryByParam="*" %>
All the attributes that we specify in an OutputCache directive are used to populate an instance of the System.Web.HttpCachePolicy class by calling. The complete implementation of cache policies provided by ASP.NET is encapsulated in the HttpCachePolicy class. Following is the another implementation of caching from code behind.Output Caching Location:
As I have already mention We can store cached data in different location like client, server or in between client and server , Now I am going to discuss how this is feasible to set location of cached data. If we store the cached data it save the page rendering time by fetching the data from catch. There is another way that we can save cached data on client browser , which reduce the network traffic. OutputCache directive on a page enables all three types of caching—server, client, and proxy—by default.
Following Table shown you the Location details . It show the location of cached and what should be the effects on Cache-Control and Expires Header.
For example, if you specified a value of 'Client' for the Location attribute of an OutputCache directive on a page, the page would not be saved in the server cache, but the response would include a Cache-Control header ( Pages can indicate whether they should be cached on a proxy by using the Cache-Control header.) value of private and an Expires header (HTTP response, indicating the date and time after which the page should be retrieved from the server again ) with a timestamp set to the time indicated by the Duration attribute
<%@ OutputCache Duration='120' Location='Client' VaryByParam='none' %>
This would save the cached for 120 second and cached data should not be saved on Server it should store only on client browser.
