Web Design for Beginner Web design tutorial Html Part-008

 Web Design for Beginner Web design tutorial Html Part-008

Web Design tutorial 29 day we are completed Web designing 


Previous Tutorial 


HTML Comments

Comment is a piece of code which is ignored by any web browser. It is a good
practice to add comments into your HTML code, especially in complex
documents, to indicate sections of a document, and any other notes to anyone
looking at the code. Comments help you and others understand your code
and increases code readability.

HTML comments are placed in between <!-- ... --> tag. So any content placed
within <!-- ... --> tag will be treated as comment and will be completely ignored
by the browser.
Example

<!DOCTYPE html>
<html>
<head>
<title>Using Image in Webpage</title>
</head>
<body>
<p>Simple Image Insert</p>
<img src="test.png" alt="Test Image" />
</body>
</html>
This will produce following result without displaying the content given as a
part of comments:

Valid vs Invalid Comments

Comments do not nest which means a comment cannot be put inside another
comment. Second the double-dash sequence "--" may not appear inside a
comment except as part of the closing --> tag. You must also make sure that
there are no spaces in the start-of-comment string.
Example
Here given comment is a valid comment and will be wiped off by the browser.

<!DOCTYPE html>
<html>
<head>
<title>Valid Comment Example</title>
</head>
<body>
<!-- This is valid comment -->
<p>Document content goes here.....</p>
</body>
</html>

But following line is not a valid comment and will be displayed by the browser.
This is because there is a space between the left angle bracket and the
exclamation mark.

<!DOCTYPE html>
<html>
<head>
<title>Invalid Comment Example</title>
</head>
<body>
< !-- This is not a valid comment -->
<p>Document content goes here.....</p>
</body>
</html>

This will produce following browser result:

Multiline Comments

So far we have seen single line comments, but HTML supports multi-line
comments as well.
You can comment multiple lines by the special beginning tag <!-- and ending
tag --> placed before the first line and end of the last line as shown in the
given example below.
Example

 <!DOCTYPE html><html>
<head>
<title>Multiline Comments</title>
</head>
<body>
<!--
This is a multiline comment and it can
span through as many as lines you like.
-->
<p>Document content goes here.....</p>
</body>
</html>


Conditional Comments

Conditional comments only work in Internet Explorer (IE) on Windows but
they are ignored by other browsers. They are supported from Explorer 5
onwards, and you can use them to give conditional instructions to different
versions of IE.
Example
<!DOCTYPE html><html>
<head>
<title>Conditional Comments</title>
<!--[if IE 6]>
Special instructions for IE 6 here
<![endif]-->
</head>
<body>
<p>Document content goes here.....</p>
</body>
</html>

 You will come across a situation where you will need to apply a different style
sheet based on different versions of Internet Explorer, in such situation
conditional comments will be helpful.

Using Comment Tag

There are few browsers that support <comment> tag to comment a part of
HTML code.
Example
<!DOCTYPE html><html>
<head>
<title>Using Comment Tag</title>
</head>
<body>
<p>This is <comment>not</comment> Internet Explorer.</p>
</body>
</html>

Commenting Script Code

Though you will learn Javascript with HTML, in a separate tutorial, but here
you must make a note that if you are using Java Script or VB Script in your
HTML code then it is recommended to put that script code inside proper HTML
comments so that old browsers can work properly.
Example
<!DOCTYPE html><html>
<head>
<title>Commenting Script Code</title>
<script>
<!--
document.write("Hello World!")
//-->
</script>
</head>
<body>
<p>Hello , World!</p>
</body>
</html>

 This will produce following browser result:

Commenting Style Sheets

Though you will learn using style sheets with HTML in a separate tutorial, but
here you must make a note that if you are using Cascading Style Sheet (CSS)
in your HTML code then it is recommended to put that style sheet code inside
proper HTML comments so that old browsers can work properly.
Example
<!DOCTYPE html><html>
<head>
<title>Commenting Style Sheets</title>
<style>
<!--
.example {
border:1px solid #4a7d49;
}
//-->
</style>
</head>
<body>
<div class="example">Hello , World!</div>
</body>
</html>

This will produce following browser result:

 ! Caution 
I can't Given any Example in the page, Because I know Every Reader read and write   

Web Design for Beginner Web design tutorial Html Part-008

Labels: , ,

Technology
loading..