Overview of the list of commonly used functions in PHP5

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Overview of the list of commonly used functions in PHP5_PHP Tutorial

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Jul 15, 2016 pm 01:35 PM

php5。binarycodefunctionliststringCommonly usedDelayimplement

usleep() function delays code execution for a number of microseconds.

unpack() function unpacks data from a binary string.

The uniqid() function generates a unique ID based on the current time in microseconds.

time_sleep_until() function delays code execution until the specified time.

The time_nanosleep() function, a commonly used function in PHP5, delays code execution for a number of seconds and nanoseconds.

sleep() function delays code execution for a few seconds.

The show_source() function performs syntax highlighting on files.

The strip_whitespace() function returns the source code file with PHP comments and whitespace characters removed.

The pack() function loads data into a binary string.

ignore_user_abort() function sets whether disconnecting from the client will terminate the execution of the script.

highlight_string() function performs syntax highlighting on strings.

The highlight_file() function performs syntax highlighting on files.

The get_browser() function, a commonly used function in PHP5, returns the performance of the user's browser.

exit() function outputs a message and exits the current script.

eval() function evaluates string according to PHP code.

die() function outputs a message and exits the current script.

defined() function checks whether a constant exists.

define() function defines a constant.

constant() function returns the value of a constant.

The connection_status() function, a commonly used function in PHP5, returns the current connection status.

The connection_aborted() function checks whether the client is disconnected.

zip_read() function reads the next file in the opened zip archive.

The zip_open() function opens a ZIP file for reading.

The zip_entry_read() function gets the contents from an open zip archive entry.

The zip_entry_open() function opens a ZIP archive entry for reading.

The zip_entry_name() function, a commonly used function in PHP5, returns the name of the zip file item.

The zip_entry_filesize() function returns the original size of the zip archive entry (before compression).

The zip_entry_compressionmethod() function returns the compression method of the zip archive entry.

The zip_entry_compressedsize() function returns the compressed file size of the zip archive entry.

The zip_entry_close() function closes the zip archive file opened by the zip_entry_open() function.

The zip_close() function closes the zip archive file opened by the zip_open() function.

xml_set_unparsed_entity_decl_handler() function specifies the function to be called when an unresolved entity name (NDATA) declaration is encountered.

The xml_set_processing_instruction_handler() function specifies the function to be called when the parser finds a processing instruction in the XML document.

The xml_set_object() function allows using XML parsers with objects.

The xml_set_notation_decl_handler() function of PHP5 commonly used functions specifies the function to be called when the parser finds a symbol declaration in the XML document.

The xml_set_external_entity_ref_handler() function specifies the function that is called when the parser finds an external entity in the XML document.

xml_set_element_handler() function establishes the starting and ending element handlers.

The xml_set_default_handler() function establishes the default data handler for the XML parser.

xml_set_character_data_handler() function creates a character data handler.

The xml_parser_set_option() function sets options for the XML parser.

The xml_parser_get_option() function gets option setting information from the XML parser.

xml_parser_free() function frees the XML parser.

The xml_parser_create() function, a commonly used function in PHP5, creates an XML parser.

xml_parser_create_ns() function creates an XML parser with namespace support.

xml_parse_into_struct() function parses XML data into an array.

xml_parse() function parses XML documents.

xml_get_error_code() function gets the XML parser error code.

xml_get_current_line_number() function gets the current line number of the XML parser.

xml_get_current_column_number() function gets the current column number of the XML parser.

The xml_get_current_byte_index() function, a commonly used function in PHP5, obtains the current byte index of the XML parser.

xml_error_string() function gets the error description of the XML parser.

utf8_encode() function encodes ISO-8859-1 string to UTF-8.

utf8_decode() function decodes UTF-8 string to ISO-8859-1.

The wordwrap() function wraps the string according to the specified length.

The vsprintf() function writes the formatted string into a variable.

vprintf() function outputs a formatted string.

The vfprintf() function writes a formatted string to the specified output stream.

The ucwords() function, a commonly used function in PHP5, converts the first character of each word in the string to uppercase.

ucfirst() function converts the first character in a string to uppercase.

trim() function removes whitespace characters and other predefined characters from both ends of a string.

substr_replace() function replaces part of a string with another string.

substr_count() function counts the number of times a substring appears in a string.

substr_compare() function compares two strings starting from the specified length.

substr() function returns a part of a string.

strtr() function converts specific characters in a string.

strtoupper() function converts a string to uppercase.

strtolower() function converts a string to lowercase.

The strtok() function, a commonly used function in PHP5, splits a string into smaller strings.

strstr() function searches for the first occurrence of a string within another string.

strspn() function returns the number of specific characters contained in a string.

strrpos() function finds the last occurrence of a string within another string.

strripos() function finds the last occurrence of a string within another string.

strrev() function reverses a string.

strrchr() function finds the last occurrence of a string within another string and returns all characters from that position to the end of the string.

strpos() function returns the position of the first occurrence of a string within another string.

Strpbrk() function, a commonly used function in PHP5, searches for any one of the specified characters in a string.

strncmp() function compares two strings.

strncasecmp() function compares two strings.

The strnatcmp() function uses a "natural" algorithm to compare two strings.

The strnatcasecmp() function uses a "natural" algorithm to compare two strings.

strlen() function returns the length of the string.

stristr() function finds the first occurrence of a string within another string.

stripos() function returns the position of the first occurrence of a string within another string.

The stripslashes() function removes the backslashes added by the addslashes() function.

The stripcslashes() function removes backslashes added by the addcslashes() function.

strip_tags() function strips HTML, XML and PHP tags.

strcspn() function returns the number of characters searched in a string before any specified character is found.

Strcoll() function, a commonly used function in PHP5, compares two strings.

strcmp() function compares two strings.

strchr() function searches for the first occurrence of a string within another string.

strcasecmp() function compares two strings.

str_word_count() function counts the number of words in a string.

str_split() function splits a string into an array.

str_shuffle() function randomly shuffles all characters in a string.

str_rot13() function performs ROT13 encoding on a string.

str_replace() function uses a string to replace other characters in a string.

str_repeat() function repeats a string a specified number of times.

str_pad() function pads a string to the specified length.

str_ireplace() function uses a string to replace other characters in a string.

The sscanf() function, a commonly used function in PHP5, parses input from a string according to the specified format.

The sprintf() function writes the formatted string into a variable.

The soundex() function calculates the soundex key of a string.

similar_text() function counts the number of matching characters in two strings.

The sha1_file() function calculates the SHA-1 hash of a file.

The sha1() function computes the SHA-1 hash of a string.

setlocale() function sets regional information (regional information).

PHP5 commonly used functions rtrim() P rtrim() function

based on the current time in microseconds

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