URL Encode (URL Encoding) Technical Explanation

URL encoding, also known as percent-encoding, is a process of converting non-standard characters into a standard URL format. When constructing or parsing a URL, certain characters may have special meanings in a URL (such as space, question mark, hash, etc.), or they may not be correctly transmitted in all systems, hence the need to encode these characters.

The principle of URL encoding is to replace each character that needs encoding with its corresponding ASCII value in hexadecimal representation, preceded by a percent sign (%). For example, the space character becomes "%20" after URL encoding.

URL Decode (URL Decoding) Technical Explanation

URL decoding is the reverse process of URL encoding, which is to restore the encoded URL characters to their original characters. Decoders recognize percent-encoded sequences in the URL and convert them back to the corresponding characters.

The main function of URL decoding is to restore the original data in the URL so that systems or applications can correctly parse and process it. During development, we often need to decode URLs input by users in order to extract information from them or perform corresponding actions.