Methods for regular expression matching URLs

Methods for regular expressions to match URLs include: Match typical URLs: (?:https?://|www.)\S .\S Extract URL Component: Protocol: ^(?:https?://|www.) Domain name: \w (?:.\w ) File path: \S*.(?:html|php|js|css) Match a specific type of URL: Image URL: (?:https?://|www.)\S .(?:jpg|jpeg|png|gif)PDF URL: (?:https?://|www.)\S .pdf

Methods for regular expressions to match URLs

Match URLs using regular expressions

Regular expressions are a powerful pattern matching language that can be used in a variety of text processing tasks, including matching URLs. The following regular expressions can match typical URLs:

 <code>(?:https?://|www\.)\S \.\S</code>

Interpretation of parts of regular expression:

• (?:https?://|www.) : This section matches the protocol part (http or https) or "www" prefix in the URL.
• \S : Match one or more non-whitespace characters to capture the domain name.
• .\S : Match a period ("."), followed by one or more non-whitespace characters, capturing the top-level domain or file extension.

Example:

The following URL conforms to the given regular expression:

• https://www.google.com/search
• http://example.com/index.html
• www.wikipedia.org

Extract URL components using regular expressions

In addition to matching URLs, regular expressions can also be used to extract various components of the URL, such as protocols, domain names, and file paths. Here are the regular expressions used to extract these components:

protocol:

 <code>^(?:https?://|www\.)</code>

domain name:

 <code>\w (?:\.\w )</code>

File path:

 <code>\S*\.(?:html|php|js|css)</code>

Use regular expressions to match URLs of specific types

Regular expressions can also be used to match URLs of specific types, for example:

Image URL:

 <code>(?:https?://|www\.)\S \.(?:jpg|jpeg|png|gif)</code>

PDF URL:

 <code>(?:https?://|www\.)\S \.pdf</code>

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