CVI. 字符串处理函数库
介绍
本函数库中的函数用来对字符串进行各种操作。对字符串其它的一些专门操作，可以参考手册的正则表达式部分和 URL 操作 部分.
预定义常量
由于这些常量是由该扩展模块定义的，因此只有在该扩展模块被编译到 PHP 中，或者在运行时被动态加载后，这些常量才有效。
- CRYPT_SALT_LENGTH integer
- CRYPT_STD_DES integer
- CRYPT_EXT_DES integer
- CRYPT_MD5 integer
- CRYPT_BLOWFISH integer
- HTML_SPECIALCHARS (integer)
- HTML_ENTITIES (integer)
- ENT_COMPAT (integer)
- ENT_QUOTES (integer)
- ENT_NOQUOTES (integer)
- CHAR_MAX (integer)
- LC_CTYPE (integer)
- LC_NUMERIC (integer)
- LC_TIME (integer)
- LC_COLLATE (integer)
- LC_MONETARY (integer)
- LC_ALL (integer)
- LC_MESSAGES (integer)
- STR_PAD_LEFT (integer)
- STR_PAD_RIGHT (integer)
- STR_PAD_BOTH (integer)
- 目录
- addcslashes -- Quote string with slashes in a C style
- addslashes -- Quote string with slashes
- bin2hex -- Convert binary data into hexadecimal representation
- chop -- Alias of rtrim()
- chr -- Return a specific character
- chunk_split -- Split a string into smaller chunks
- convert_cyr_string -- Convert from one Cyrillic character set to another
- count_chars -- Return information about characters used in a string
- crc32 -- Calculates the crc32 polynomial of a string
- crypt -- One-way string encryption (hashing)
- echo -- Output one or more strings
- explode -- Split a string by string
- fprintf -- Write a formatted string to a stream
- get_html_translation_table -- Returns the translation table used by htmlspecialchars() and htmlentities()
- hebrev -- Convert logical Hebrew text to visual text
- hebrevc -- Convert logical Hebrew text to visual text with newline conversion
- html_entity_decode -- Convert all HTML entities to their applicable characters
- htmlentities -- Convert all applicable characters to HTML entities
- htmlspecialchars -- Convert special characters to HTML entities
- implode -- Join array elements with a string
- join -- Alias of implode()
- levenshtein -- Calculate Levenshtein distance between two strings
- localeconv -- Get numeric formatting information
- ltrim -- Strip whitespace from the beginning of a string
- md5_file -- Calculates the md5 hash of a given filename
- md5 -- Calculate the md5 hash of a string
- metaphone -- Calculate the metaphone key of a string
- money_format -- Formats a number as a currency string
- nl_langinfo -- Query language and locale information
- nl2br -- Inserts HTML line breaks before all newlines in a string
- number_format -- Format a number with grouped thousands
- ord -- Return ASCII value of character
- parse_str -- Parses the string into variables
- print -- Output a string
- printf -- Output a formatted string
- quoted_printable_decode -- Convert a quoted-printable string to an 8 bit string
- quotemeta -- Quote meta characters
- rtrim -- Strip whitespace from the end of a string
- setlocale -- Set locale information
- sha1_file -- Calculate the sha1 hash of a file
- sha1 -- Calculate the sha1 hash of a string
- similar_text -- Calculate the similarity between two strings
- soundex -- Calculate the soundex key of a string
- sprintf -- Return a formatted string
- sscanf -- Parses input from a string according to a format
- str_ireplace -- Case-insensitive version of str_replace().
- str_pad -- Pad a string to a certain length with another string
- str_repeat -- Repeat a string
- str_replace -- Replace all occurrences of the search string with the replacement string
- str_rot13 -- Perform the rot13 transform on a string
- str_shuffle -- Randomly shuffles a string
- str_split -- Convert a string to an array
- str_word_count -- Return information about words used in a string
- strcasecmp -- Binary safe case-insensitive string comparison
- strchr -- Alias of strstr()
- strcmp -- Binary safe string comparison
- strcoll -- Locale based string comparison
- strcspn -- Find length of initial segment not matching mask
- strip_tags -- Strip HTML and PHP tags from a string
- stripcslashes -- Un-quote string quoted with addcslashes()
- stripos -- Find position of first occurrence of a case-insensitive string
- stripslashes -- Un-quote string quoted with addslashes()
- stristr -- Case-insensitive strstr()
- strlen -- Get string length
- strnatcasecmp -- Case insensitive string comparisons using a "natural order" algorithm
- strnatcmp -- String comparisons using a "natural order" algorithm
- strncasecmp -- Binary safe case-insensitive string comparison of the first n characters
- strncmp -- Binary safe string comparison of the first n characters
- strpos -- Find position of first occurrence of a string
- strrchr -- Find the last occurrence of a character in a string
- strrev -- Reverse a string
- strripos -- Find position of last occurrence of a case-insensitive string in a string
- strrpos -- Find position of last occurrence of a char in a string
- strspn -- Find length of initial segment matching mask
- strstr -- Find first occurrence of a string
- strtok -- Tokenize string
- strtolower -- Make a string lowercase
- strtoupper -- Make a string uppercase
- strtr -- Translate certain characters
- substr_compare -- Binary safe optionally case insensitive comparison of 2 strings from an offset, up to length characters
- substr_count -- Count the number of substring occurrences
- substr_replace -- Replace text within a portion of a string
- substr -- Return part of a string
- trim -- Strip whitespace from the beginning and end of a string
- ucfirst -- Make a string's first character uppercase
- ucwords -- Uppercase the first character of each word in a string
- vprintf -- Output a formatted string
- vsprintf -- Return a formatted string
- wordwrap -- Wraps a string to a given number of characters using a string break character.