div css features and advantages_html/css_WEB-ITnose

< DOCTYPE html PUBLIC -WCTDD When building a div css js file, the performance, structure, and behavior should be separated. Doing so is just like the mvc mode we use to make programs. The advantage is that it is less coupled and easier to maintain. Because the code is small and the structure is clear.

2. Speed

The advantage of speed is considered in two points
Bandwidth occupied

At least better than

< /td>

Write a lot less code
Table nesting is generally

td>
                                                                                                                It is indeed much less than table.
Web page execution speed
1) Overall display speed. Anyone who has learned the principles of compilation knows that grammatical analysis is required. In IE or other browsers, you must first analyze the meaning. In this case, the div is simple and can be easily matched. For the time being, imagine using the stack method to do the analysis.
2) Customer experience
If it is a nested table, you are out of luck. If the last is not executed, the whole thing is just a whiteboard
And for divs, you can display part of it first. The customer experience is also much better. The principle is related to the first one
3. Optimization for search engines
Once the crawler comes up and loads your web page, if it is a nested table, it will have to process a lot of To analyze a table with a complex structure, it is not easy to write a regular expression, but div is different and is obviously much simpler. Search engines like clean code (the real meaning is that it increases the proportion of effective keywords in the total code of the web page), so websites made using the CSS+DIV web standard have certain advantages of being search engine friendly.


However, the shortcomings of CSS DIV website construction are also obvious at this stage:

Comparing table layout and CSS DIV, we found that CSS syntax is actually very easy and convenient, and designers also admit that mastering it CSS+DIV does not require knowledge as profound as making a rocket fly into the sky, but certain concepts do still require them to digest and absorb. At the same time, bug problems are also one of the reasons that prevent the popularity of CSS. Even web professionals often spend a lot of time fixing bugs, not to mention those novices who use CSS. In-depth comparison found that some problems that can be easily solved through tables become complicated when using CSS DIV. If you are a CSS enthusiast, this may be a challenge and fun for him, but for ordinary designers, this is undoubtedly Frustrating.

In addition, if the design elements of most websites are evenly distributed throughout the site, the design elements of CSS website production are usually placed in several external files. This one or several files may be quite complex. , the file is not small, and the problems caused by it will not be ignored. For example, if the CSS file is called abnormally, the entire website will become miserable.

Browser compatibility issues are also currently hindering CSS DIV. Pages that may be displayed normally in IE are completely different in FireFox. CSS DIV still needs further support from browser manufacturers. Various reasons make the popularization of web standards have a high threshold, which is also the sense of superiority of many web standard advocates.

For the search engine friendliness that Internet marketers are most concerned about, it is well known that search engines like clean code (its real meaning is to increase the proportion of effective keywords in the total code of the web page), so use CSS+DIV Websites made with web standards have certain advantages of being search engine friendly. However, the inclusion and ranking of web pages by search engines is obviously not measured by whether tables and CSS positioning are used. This is why many websites made with traditional table layouts are ranked highly, while many web pages made using CSS and web standards are still ranked. The reason behind. Because for search engines, content, structure, links and other factors are always the most important indicators for website optimization.

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