Recently, I found that CSS is forgotten, so I need to review CSS again. I will open this series to review and update the knowledge I have learned. After all, the old is the new.
Simple selector
First, some basic selectors, which I categorize as simple selectors. I won’t go into their usage here.
* {}
Wildcard selector
e { }
Element selector
#id { }
Id selector that allows only one occurrence in the page. It also has the highest weight
.calss { }
Class selector, which can appear multiple times
<! Class ="class1 class2"></div\> An element can have more than one class separated by a space.Copy the code
Property selector
There is a class of selectors that select elements’ attributes and need to be used in conjunction with element selectors, which I will call attribute selectors
Property selectors are wrapped with []. Attribute values should also be quoted.
e[attr] { }
The element with the attr attribute
e[attr=”val”] { }
The element with the attr attribute and the value val.
e[attr|=”val”] { }
The attr attribute has a value of val or an element beginning with val-
The value must be the entire word or hyphenated.
e[attr^=”val”] { }
The element whose value of the attr attribute begins with val
e[attr$=”val”] { }
The element whose value of the attr attribute ends in val
e[attr~=”val”] { }
The attr attribute contains the element with the value val
Use to select the element whose attribute value contains the specified term. Separate words with Spaces
e[attr*=”val”] { }
The value of the attr attribute contains elements of val
You can find two that start with a value and two that contain properties
Let’s break down the differences
<a title="web">1</a\>
<a title="website">2</a\>
<a title="web-site">3</a\>
<a title="web site">4</a\>
Copy the code
The first is to start with the value
1,2,3, and 4 elements are selected for a[title^=”web”]{}
For a [title | = “web”] {}. The only selected 1, 3
We can draw
A [title^=”web”]{}. The property value is treated as an entire string, as long as it begins with web. Is selected
A [title | = “web”] {} is selected web or web – at the beginning. Two words need to be connected with –
Then include the value
1,2,3, and 4 elements are selected for a[title*=”web”]{}
For a[title~=”web”]{}. Only 1,4 are selected
We can draw
A [title*=”web”]{}. Property value String As long as there is web, select
A [title~=”web”]{} Yes The corresponding word web is selected. Separate multiple words with Spaces
Upper selector
The next selector is one level up from the previous selector. Kind of a selector of a selector. This is what I call the top selector (this is my own understanding of the classification)
E F { }
Descendant selectors that match all F selector elements (including children and grandchildren) below E selector elements, separated by a space
E>F { }
Child element selector, the only element that matches the E selector is the F selector in its children. Their grandchildren will not choose it
E+F { }
Adjacent sibling selectors, the first f-conforming element of the sibling immediately after the e-conforming element, have the same parent.
E~F { }
Full-sibling selectors, which select F selectors from all siblings that match E selectors.
EF { }
An intersection selector that matches both an E selector element and an F selector element, with no Spaces in between
E,F { }
Union (multi-element) selectors that match elements conforming to E or F, separated by commas
The basic CSS selectors are now reviewed. Next, I will tidy up some common CSS properties, and update my lack of content and use skills