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HomeWeb Front-endFront-end Q&AWhat is the difference between id and class in html

Difference: 1. The scope of class is larger than that of id. ID is unique and can only be called once in a page, while class can be called multiple times; 2. ID corresponds to the style selector of CSS. is "#", and the style selector corresponding to class in CSS is "."; 3. The priority of the id selector is higher than the class selector.

What is the difference between id and class in html

The operating environment of this tutorial: Windows 7 system, CSS3&&HTML5 version, Dell G3 computer.

Comparison of class and id in Html:

1. The scope of effect is different:

class has a larger range than id, which represents a unique identifier, just like our personal ID card. It is unique and can only be called once on a page. Generally, a web page does not have two or more IDs. The scope of class is wider. Class is a class label and can be called multiple times in an interface. Can be reused.

2. The syntax used is different:

How the id selector is used in css, such as using div as an example: (For example, there are div respectively id='i'... and div class='c'...Two div boxes, the methods quoted in css are as follows:)

.c{
属性:属性值;
} 
#i{
属性:属性值;
}

3. Priority The levels are different:

The priority of the id selector is higher than the priority of the class selector. For more important ones, you can use the id selector.

Recommended tutorial: "html video tutorial"

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