Sams Teach Yourself Web Publishing with HTML and CSS in One Hour a Day (5th Edition) P17 doc

Character-Level Elements HTML 3.2 defined several additional physical style tags, including the following: Underline (deprecated in HTML 4.0) <s> Strikethrough (deprecated in HTML 4.0) <big> Bigger print than the surrounding text Smaller print Subscript Superscript Note Text-based browsers, such as Lynx and those associated with wireless devices, can't render bold, italic, or other styled text. They generally highlight the text in some way, but the method varies depending on the browser and platform. You can nest character tagsfor example, using both bold and italic for a set of charactersas follows: Text that is both bold and italic However, the result on the screen is browser-dependent, like all HTML tags. You won't necessarily end up with text that's both bold and italic. You might end up with one style or the other: Input In Dante's Inferno, malaboge was the eighth circle of hell, and held the malicious and fraudulent. All entries must be received by September 26, 1999. Type <tt>lpr -Pbirch myfile.txt</tt> to print that file. Sign your name in the spot marked Sign Here: People who wear orange shirts and plaid pants <s>have no taste</s> are fashion-challenged. RCP floor mats give you <big>big</big> savings over the competition! Then, from the corner of the room, he heard a tiny voice . In heavy trading today. Consolidated Orange Trucking rose 1/4 points on volume of 1,457,900 shares. Figure 6.2 shows some of the physical tags and how they appear. Output Figure 6.2. Physical styles displayed in a browser. file:///G|/1/0672328860/ch06lev1sec1.html (5 von 6) [19.12.2006 13:48:43] Character-Level Elements [View full size image] file:///G|/1/0672328860/ch06lev1sec1.html (6 von 6) [19.12.2006 13:48:43] Character Formatting Using CSS Character Formatting Using CSS You've already seen how styles can be used to modify the appearance of various elements. Any of the effects associated with the tags introduced in today's lesson can also be created using CSS. Before I go into these properties, however, I want to talk a bit about how to use them. As I've said before, the style attribute can be used with most tags. However, most tags somehow affect the appearance of the text that they enclose. There's a tag that doesn't have any inherent effect on the text that it's wrapped around: the tag. It exists solely to be associated with style sheets. It's used exactly like any of the other tags you've seen today. Simply wrap it around some text, like this: This is an example of the usage of the span tag. Used by itself, the tag has absolutely no effect. Paired with the style attribute, it can take the place of any of the tags you've seen today and can do a lot more than that as well. The Text Decoration Property The text-decoration property is used to specify which, if any, decoration will be applied to the text within the affected tag. The valid values for this property are underline, overline, line-through, and blink. The application of each of them is self-explanatory. However, here's an example that demonstrates how to use each of them: Input Here is some underlined text. Here is some overlined text. Here is some line-through text. Here is some blinking text. Using and the text-decoration property to underline text is no different from using the tag, except that some old browsers that don't support CSS might not support it. The cool thing is that you can use this, and all the properties you'll see in today's lesson, with any tag that encloses text. Take a look at this example: <h1 style="text-decoration: underline">An Underlined Heading</h1> Using the style attribute, you can specify how the text of the heading appears. Choosing between this approach and the tag is a washif you want to remove the underlining from the heading, you'd have to come back and edit the tag itself, regardless of whether you used the tag or style attribute. Later, you'll see how style sheets can be used to control the appearance of many elements at once. Font Properties When you want to modify the appearance of text, the other major family of properties you can use is file:///G|/1/0672328860/ch06lev1sec2.html (1 von 3) [19.12.2006 13:48:43] Character Formatting Using CSS font properties. Font properties can be used to modify pretty much any aspect of the type used to render text in a browser. One of the particularly nice things about font properties is that they're much more specific than the tags that you've seen so far. First, let's look at some of the direct replacements for tags you've already seen. The font-style property can be used to italicize text. It has three possible values, normal, which is the default, italic, which renders the text in the same way as the tag, and oblique, which is somewhere between italic and normal, and is not as well supported by browsers as the italic style is. Here are some examples: Input Here's some italicized text. Here's some oblique text (which may look like regular italics in your browser). Now let's look at how you use CSS to create boldfaced text. In the world of HTML, there are two options: bold and not bold. With CSS, you have (theoretically) many more options. The reason I say theoretically is that browser support for the wide breadth of font weights available using CSS can be spotty. To specify that text should be boldface, the font-weight property is used. Valid values are normal (the default), bold, bolder, lighter, and 100 through 900, in units of 100. Here are some examples: Input Here's some bold text. Here's some bolder text. Here's some lighter text. Here's some bolder text. You can also set the typeface for text using the font-family property. You can also set the specific font for text, but I'm not going to discuss that until later today. In the meantime, let's look at how you can set the font to a member of a particular font family. The specific font will be taken from the user's preferences. The property to modify is font-family. The possible values are serif, sans-serif, cursive, fantasy, and monospace. So, if you want to specify that a monospace font should be used with CSS instead of the <tt> tag, you would use the following code: Input This is monospaced text. Now let's look at one capability that's not available using regular HTML tags. Using the font-variant property, you can have your text rendered so that lowercase letters are replaced with larger capital letters. The two values available are normal and small-caps. Here's an example: Input This Text Uses Small Caps. file:///G|/1/0672328860/ch06lev1sec2.html (2 von 3) [19.12.2006 13:48:43] Character Formatting Using CSS The browser window in Figure 6.3 contains some text that uses the font-variant property as well as all the other properties described in this section. Output Figure 6.3. Text styled using CSS. [View full size image] file:///G|/1/0672328860/ch06lev1sec2.html (3 von 3) [19.12.2006 13:48:43] Preformatted Text Preformatted Text Most of the time, text in an HTML file is formatted based on the HTML tags used to mark up that text. As I mentioned in Lesson 3, "Introducing HTML and XHTML," any extra white space (spaces, tabs, returns) that you put in your text is stripped out by the browser. The one exception to this rule is the preformatted text tag <pre>. Any white space that you put into text surrounded by the <pre> and </pre> tags is retained in the final output. With these tags, the spacing in the text in the HTML source is preserved when it's displayed on the page. The catch is that preformatted text usually is displayed (in graphical displays, at least) in a monospaced font such as Courier. Preformatted text is excellent for displaying code examples in which you want the text formatted with exactly the indentation the author used. Because you can use the <pre> tag to align text by padding it with spaces, you can use it for simple tables. However, the fact that the tables are presented in a monospaced font might make them less than ideal. (You'll learn how to create real tables in Lesson 8, "Building Tables.") The following is an example of a table created with <pre>: Input <pre> Diameter Distance Time to Time to (miles) from Sun Orbit Rotate (millions of miles) Mercury 3100 36 88 days 59 days Venus 7700 67 225 days 244 days Earth 7920 93 365 days 24 hrs Mars 4200 141 687 days 24 hrs 24 mins Jupiter 88640 483 11.9 years 9 hrs 50 mins Saturn 74500 886 29.5 years 10 hrs 39 mins Uranus 32000 1782 84 years 23 hrs Neptune 31000 2793 165 days 15 hrs 48 mins Pluto 1500 3670 248 years 6 days 7 hrs </pre> Figure 6.4 shows how it looks in a browser. Output Figure 6.4. A table created using <pre>, shown in a browser. [View full size image] file:///G|/1/0672328860/ch06lev1sec3.html (1 von 3) [19.12.2006 13:48:44] Preformatted Text When you're creating text for the <pre> tag, you can use link tags and character styles, but not element tags such as headings or paragraphs. You should break your lines with hard returns and try to keep your lines to 60 characters or fewer. Some browsers might have limited horizontal space in which to display text. Because browsers usually won't reformat preformatted text to fit that space, you should make sure that you keep your text within the boundaries to prevent your readers from having to scroll from side to side. Be careful with tabs in preformatted text. The actual number of characters for each tab stop varies from browser to browser. One browser might have tab stops at every fourth character, whereas another may have them at every eighth character. You should convert any tabs in your preformatted text to spaces so that your formatting isn't messed up if it's viewed with different tab settings than in the program you used to enter the text. The <pre> tag is also excellent for converting files that were originally in some sort of text-only form, such as mail messages or Usenet news postings, into HTML quickly and easily. Just surround the entire content of the article within <pre> tags and you have instant HTML, as in the following example: <pre> To: lemay@lne.com From: jokes@lne.com Subject: Tales of the Move From Hell, pt. 1 I spent the day on the phone today with the entire household services division of northern California, turning off services, turning on services, transferring services and other such fun things you have to do when you move. It used to be you just called these people and got put on hold for and interminable amount of time, maybe with some nice music, and then you got a customer representative who was surly and hard of hearing, but with some work you could actually get your phone turned off. </pre> One creative use of the <pre> tag is to create ASCII art for your web pages. The following HTML input and output example shows a simple ASCII-art cow: file:///G|/1/0672328860/ch06lev1sec3.html (2 von 3) [19.12.2006 13:48:44] Preformatted Text Input <pre> ( ) Moo (oo) \/ \ || | \ || W|| * || || </pre> The result is displayed in Figure 6.5. Output Figure 6.5. A bit of ASCII art that illustrates how preformatted text works. file:///G|/1/0672328860/ch06lev1sec3.html (3 von 3) [19.12.2006 13:48:44] Horizontal Rules Horizontal Rules The <hr> tag, which has no closing tag in HTML and no text associated with it, creates a horizontal line on the page. Rule lines are used to visually separate sections of a web pagejust before headings, for example, or to separate body text from a list of items. Closing Empty Elements The <hr> tag has no closing tag in HTML. To convert this tag to XHTML and to ensure compatibility with HTML browsers, add a space and a forward slash to the end of the tag: <hr /> If the horizontal line has attributes associated with it, the forward slash still appears at the end of the tag, as shown in the following examples: <hr size="2" /> <hr width="75%" /> <hr align="center" size="4" width="200" /> The following input shows a rule line and a list as you would write it in XHTML 1.0: Input <hr /> <h2>To Do on Friday</h2> <ul> <li>Do laundry</li> <li>Send FedEx with pictures</li> <li>Have lunch with Mollie</li> <li>Read Email</li> <li>Set up Ethernet</li> </ul> <hr /> Figure 6.6 shows how they appear in a browser. Output file:///G|/1/0672328860/ch06lev1sec4.html (1 von 5) [19.12.2006 13:48:44] Horizontal Rules Figure 6.6. An example of how horizontal rules are used around a list. Attributes of the <hr> Tag In HTML 2.0, the <hr> tag is just as you see it, with no closing tag or attributes. However, HTML 3.2 introduced several attributes to the <hr> tag that give you greater control over the appearance of the line drawn by <hr>. All these attributes have been deprecated in favor of style sheets in the HTML 4.01 specification. Note Although presentation attributes such as size, width, and align are still supported in HTML 4.01, style sheets are now the recommended way to control a page's appearance. The size attribute indicates the thickness, in pixels, of the rule line. The default is 2, and this also is the smallest that you can make the rule line. Figure 6.7 shows the sample rule line thicknesses created with the following code: Input <h2>2 Pixels</h2> <hr size="2" /> <h2>4 Pixels</h2> <hr size="4" /> <h2>8 Pixels</h2> <hr size="8" /> <h2>16 Pixels</h2> <hr size="16" /> Output file:///G|/1/0672328860/ch06lev1sec4.html (2 von 5) [19.12.2006 13:48:44] . that lowercase letters are replaced with larger capital letters. The two values available are normal and small-caps. Here's an example: Input tag is a washif you want to remove the underlining from the heading, you'd have to come back and edit the tag itself,. has no closing tag in HTML. To convert this tag to XHTML and to ensure compatibility with HTML browsers, add a space and a forward slash to the end of the tag: <hr /> If the horizontal

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