1. The table label is a table, tr is a row, td is a cell, cellpacing is the distance between the cell and the cell cellpadding is the margin, caption is the title of the table colspan is the merge column, rowspan is the parallel, table tbody
All are default. If you add multiple tdody, you can solve the problem of page display.
2. Hyperlink email link mailto: [email protected]
3. <input type=file> can be passed for a long time
4.lable can set shortcut keys
5.ini is a simple configuration information description, while xml is a complex information description
6. Regular expression is a rule specifically used to manipulate strings
Simplify string operation by means of some symbols
Common operations include
Matches
Find: pattern, and macther objects
Cut: split
Replace: replaceAll
Web crawler: source files read through the network and io, and obtain the numbers in the web page that match the rules through rules
The meaning of groups in regular expressions: encapsulate part of them for reuse. Direction reference group
7.html is a hypertext markup language. The html language is composed of tags. The data in html will be packaged in the tag, because the data in the package can be operated on by changing the attribute value in the tag.
Determine the html code range. <html></html>
In this range, two parts can be defined, one is the head, and one is the body,
Tag features: For data encapsulation, there are start tags and end tags, but some tags only have one function, so there is no need for end tags. The specification requires that the tags must be ended, so such tags end internally.
8. Common tags <font></font>.
Title tag <h1><h2><h3>
List tags: <dl></dl>
Upper level project: <dt>
Lower project: <dd>
Bullet tag: <ul> is unsigned
<ol> is signed
Both list items have <li> encapsulation
Image tag: <img>
Table tag: <table> consists of rows and row cells, and there is a default tbody tag in the table.
Tables are formatted for tables.
Hyperlink tag: <a href=>Sina website target
When clicked, the corresponding parser will be started.
Go to find the specified host.
One function of hyperlink: positioning marks
Form tag: This tag can interact with the server.
There are 10 types: text, password, file, checkbox, radio, hidden, button, submit, reset, image
Images all have submission function
Drop-down menu:
<select >
<option></option>
</select>
Text area: <textarea> Form components usually need to define name and value properties
9. Form components usually need to define name and value attributes because they are sent to the server.
10. The difference between get and post
get: The submitted data will be displayed on the address bar
post: The data will not be displayed on the address bar
get: The size of the submitted data office will be limited by the address bar
Post: Can submit large-volume data
get: Not safe for sensitive information
post: Security for sensitive information
get: The commit message will be encapsulated in the request line, that is, before the header of the http message header
post: The submitted information will be encapsulated in the data line, that is, after the blank line after the http message header
Components using forms do not necessarily define form tags. Form tags are used only when data needs to be submitted on the server side.
11.css Cascading Style Sheet
Separate the styles in the web page, and have completely controlled them with CSS
Enhanced style reusability and scalability
Format: Selector
Four ways to combine Css and html code
1.Every html tag uses a style attribute
2. When there are multiple tags on the page with the same style, it can be reused.
3. When there are the same styles of the tags in multiple pages, you can also encapsulate the styles into a css by defining them in each page.
4. Link in the head tag through html
12. Selector:
1. Tag Selector
2. Class selector
3. id selector
Priority id>class> tags
Extended selector
1Association selector: Actually style the tags in the tag
2 combination selectors:
3. Pseudo-element selector:
13. The difference between div and span
Div: Row-level area
Span: Block-level area