It is actually very simple to write inline styles using HTML's style attribute. Just add style="..." to the tag and then write CSS rules in it. 1. The basic writing method is a CSS style with the attribute value in the form of a string. Each style is separated by a semicolon. The format is the attribute name: attribute value, for example:

This paragraph of text is red. Note that the entire style string should be wrapped in double quotes. A semicolon should be added after each CSS attribute. The attribute name is standard writing method of CSS; 2. Applicable scenarios for inline styles include dynamic style control, email template development and rapid debugging. For example, if the picture is displayed in the center, you can write it as ; 3. Several pitfalls that need to be avoided include high priority but difficult to maintain, many code repetitions, and special character escape problems. Common errors include the camel of the attribute name, forgetting to add colons or using Chinese punctuation; 4. Compared with class, the style attributes have poor maintenance, low reusability, and convenient dynamic control, while the class CSS file has good maintenance, high reusability, and slightly complex dynamic control. Therefore, unless there is a clear reason, try to use style as little as possible, but use class to manage styles through class. Mastering the correct way to use can help you save a lot of trouble when the right time.

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Want to write inline styles using HTML's style attribute? In fact, it is very simple. Just add style="..." to the tag and then write CSS rules in it. However, how to write it easily and without making any mistakes, there are still some details to pay attention to.

1. Basic writing method: attribute value is a CSS style string

The HTML style attribute accepts a string CSS style rule. Each style is separated by a semicolon, and the format is屬性名: 屬性值. For example:

 <p   style="max-width:90%">This paragraph is red</p>

• Note that you should wrap the entire style string in double quotes.
• Each CSS attribute needs to be followed by a semicolon (although the last one can be omitted, it is recommended to add consistency).
• Property names are written in CSS, such as font-size instead of camel or underscore.

2. Applicable scenarios for inline styles

Although it is now recommended to write styles in external CSS files, style attribute also has its use:

• Dynamic style control : It is very convenient to directly modify the style of an element with JavaScript.
• Mail template development : Many email clients have limited support for CSS, and the inline style is more stable.
• Quick debugging : Temporarily test a certain style effect, and do not want to move external files.

For example, if you just want a certain image to be displayed in the center and don’t want to add a class to it, you can write it like this:

 <img  src="/static/imghw/default1.png"  data-src="photo.jpg"  class="lazy"   style="max-width:90%" alt="How to use the style html attributes for inline CSS?" >

3. Several pitfalls to avoid

Although convenient, style attribute also has some usage restrictions and common errors:

• High priority but difficult to maintain : because the priority of inline styles is higher than that of most CSS, it is easy to overwrite other styles, and it is troublesome to modify later.
• The code is repeated many times : if multiple elements require the same style, each of them will lose its reusability.
• Pay attention to special character escape : If you use JavaScript to dynamically generate style strings, remember to process spaces, quotes, etc.

Some common error examples:

 <!-- Error: The attribute name is written as camel-->
<div style="fontSize: 20px;"></div>

<!-- Error: Forgot to add a colon -->
<div style="color red;"></div>

<!-- Error: Chinese punctuation was used-->
<div style="color:red;"></div>

4. A simple comparison with class

So unless there is a clear reason, try to use style as little as possible, and instead manage styles through class.

Basically that's it. Inline styles are not complicated, but they are easily abused or ignored in actual projects. Mastering the correct way to use can help you save a lot of trouble when the right time.

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