URL syntax for URLs

First, the syntax of the URL

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Agreement

-The full format of the URL

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-Scheme: scheme that specifies which protocol gets the specified resource from the server; the scheme name is not case-sensitive. Common scenarios: HTTP, HTTPS, FTP, MAILTO, RTSP, FILE, NEWS, Telnet, and more

Host/port number

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-Host: hostname, IP address or domain name of the server where the resource resides (requires DNS to be converted to an IP address)

-Port: Port number, each service on the server corresponding to a listening port number

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-Strictly speaking, a service program provided externally in a computer can be bound to any idle port, thereby enabling the task of listening for client connection requests.

-Common protocols set some default port numbers and should try to avoid mixing

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User name/password

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-User: Username, some programs need to specify user name when accessing resources, default value is AnonyMouse

-PWD: Password, default value is <e-mail> address

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Path

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-Path: path, local name of the resource on the server, separated by a slash (/) from the preceding URL component

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Parameters

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-PARAMS: parameters, some scenarios use parameters to specify input parameters, each with a "name/value pair" form, a URL can have multiple such "name/value pairs", using semicolons (;) delimited

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Query string

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-Query: Queries strings, some scenarios use query strings to pass parameters to activate applications such as databases, bulletin boards, search engines, and other Internet gateways. Query string contents are not formatted, use? separate from other components

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Anchor Point (Bookmark)

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-FRAG: Fragment, also known as anchor (anchor point)/tag (bookmark), refers to the name of a part of a resource. When referencing an object, the Frag field is not delivered to the server, which is used internally by the client, separated by # from other parts

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Relative URL

-Two types of URLs

-absolute URL: Starts with the scheme and contains all the information required to access the resource

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-relative URL: Does not start with a scheme, the URL itself contains incomplete information, must refer to another URL (base, base URL) to determine its full content information

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Summary: This chapter mainly introduces the URL syntax of URLs

This article from the "Flying Ants" blog, declined to reprint!

URL syntax for URLs