简介

本类函数用来对字符串进行各种操作。对字符串的一些其它专门操作，可以参考手册的正则表达式部分和 URL 操作部分。

如果想要了解字符串的相关内容，特别是有关单引号，双引号等的处理部分，可以参考手册中类型部分中的字符串条目。

需求

要编译本扩展模块无需外部库文件。

安装

本扩展模块作为 PHP 内核的一部分，无需安装即可使用。

预定义常量

以下常量由本扩展模块定义，因此只有在本扩展模块被编译到 PHP 中，或者在运行时被动态加载后才有效。

参见

如果想更深入的了解有关字符串高级操作的相关内容，请参阅手册的 POSIX 扩展正则表达式函数和 Perl 兼容正则表达式函数部分。

目录

addcslashes 以 C 语言风格使用反斜线转义字符串中的字符

addslashes 使用反斜线引用字符串

bin2hex 将二进制数据转换成十六进制表示

chop rtrim() 的别名

chr 返回指定的字符

chunk_split 将字符串分割成小块

convert_cyr_string 将字符由一种 Cyrillic 字符转换成另一种

convert_uudecode Decode a uuencoded string

convert_uuencode Uuencode a string

count_chars 返回字符串所用字符的信息

crc32 计算一个字符串的 crc32 多项式

crypt One-way string encryption (hashing)

echo Output one or more strings

explode 使用一个字符串分割另一个字符串

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_decode Convert special HTML entities back to characters

htmlspecialchars Convert special characters to HTML entities

implode Join array elements with a string

join 别名 implode()

levenshtein Calculate Levenshtein distance between two strings

localeconv Get numeric formatting information

ltrim Strip whitespace (or other characters) from the beginning of a string

md5_file Calculates the md5 hash of a given file

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 (or other characters) 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_getcsv Parse a CSV string into an array

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 别名 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

strpbrk Search a string for any of a set of 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 (or other characters) 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

vfprintf Write a formatted string to a stream

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