Adding a shared page to an html page _ javascript tips

Reference A subpage in a static html page. Similar to the dynamic page mode, How do I include one HTML file inside another?
It's very common practice to have a consistent theme on a web site. you might have a standard navigation bar or a logo or even just a page footer with copyright and administrative information. rather than actually having that information on each and every page it wocould certainly be nice if you cocould write your navigation bar once, keep it in one file, and then reference that file in each of several different pages. make a change to the navigation bar in one place and instantly all pages are updated.
Welcome to "include" files-an incredibly powerful facility that can do this, and so much more, on your web site.
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Includes break down into two categories: client and server. A "client" side include is one completed MED by your browser. unfortunately, there is no specific syntax in HTML for client side includes so we have to play a small game using javascript. A "server" side include is exactly that-the include happens on your web server so the client browser never even knows it happened.
Server Side encryption DES
We'll start with the conceptually easier one: the server side include. The specific syntax will vary based on what type of server you have and what your pages are written in.
Simple HTML pages on most common web servers can use a syntax called Server Side Include, or SSI. As an example in an HTML file a.html we can place this line:

The page seen by a browser viewing a.html will consist of the contents of a.html before the include line, followed by the contents of B. inc, followed by the contents of a.html after the include line. put the HTML for your navigation bar in a file like B. inc, and all your pages can show the exact same bar.
SSI is available on both Apache and Microsoft IIS web servers. on Apache some configuration may be needed but even if you don't have access to the actual server configuration files it can typically also be enabled by commands in a file named. htaccess that you will either find or can create in your server's web directory. read more about Apache SSI here. under IIS, SSI is enabled anytime you use ". asp "pages -- so the only configuration you need do is to name your pages. asp instead. html. read more about Server Side Include in ASP pages here.
Another popular ASP-like programming environment is PHP. PHP's include syntax is very simple:

Naturally, PHP has a host of additional processing ability but much like ASP the only requirement to make the include abve work is to have PHP on your web server and name your file ". php ".
With all of the above approaches, the browser viewing the page knows absolutely nothing about the include-it all happened before the page was downloaded. however, sometimes processing an include on the server isn' t the right option. that's where processing an include on the client comes in.
Client Side encryption DES
As I mentioned above, there is no actual syntax for a client-side include but we can mimic one using Javascript. For example: