Here is an alphabetical list of PHP’s built-in String functions.
| Function | Description |
|---|---|
| addcslashes() | Returns a string with backslashes before the specified characters |
| addslashes() | Returns a string with backslashes before the characters that need to be escaped. These characters are single quote , double quote, backslash (\) and NULL |
| bin2hex() | Convert binary data into hexadecimal values |
| chop() | Strip whitespace (or other characters) from the end of a string. Alias of rtrim() function |
| chr() | Returns a one-character string containing the character specified by ASCII |
| chunk_split() | Split a string into smaller chunks |
| convert_cyr_string() | Converts a string from one Cyrillic character set to another |
| convert_uudecode() | Decodes a uuencoded string |
| convert_uuencode() | Encodes a string using the uuencode algorithm |
| count_chars() | Returns information about characters used in a string |
| crc32() | Calculates the crc32 polynomial of a string |
| crypt() | One-way string encryption (or hashing) |
| echo() | Outputs one or more strings |
| explode() | Split a string into an array by a specified string |
| fprintf() | Write a formatted string to a specified output stream |
| get_html_translation_table() | Returns the translation table used by htmlspecialchars() and htmlentities() |
| hebrev() | Convert logical Hebrew text to visual text |
| hex2bin() | Decodes a hexadecimally encoded binary string |
| 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() | Returns a string by joining the elements of an array with a specified string |
| join() | Alias of implode() function |
| lcfirst() | Converts the first character of a string to lowercase |
| levenshtein() | Calculate Levenshtein distance between two strings |
| localeconv() | Returns localized numeric and monetary formatting information |
| ltrim() | Removes whitespace (or other characters) from the beginning of a string |
| md5() | Calculate the md5 hash of a string |
| md5_file() | Calculates the md5 hash of a file |
| metaphone() | Calculate the metaphone key of a string |
| nl_langinfo() | Returns specific local information |
| nl2br() | Inserts HTML line breaks before all newlines in a string |
| number_format() | Format a number with grouped thousands |
| ord() | Returns the ASCII value of the first character of a string |
| parse_str() | Parses the string into variables |
| print() | Outputs a string |
| printf() | Outputs a formatted string |
| quoted_printable_decode() | Convert a quoted-printable string to an 8 bit string |
| quoted_printable_encode() | Convert a 8 bit string to a quoted-printable string |
| quotemeta() | Quotes meta characters |
| rtrim() | Removes whitespace (or other characters) from the end of a string |
| setlocale() | Set locale information |
| sha1() | Calculate the sha1 hash of a string |
| sha1_file() | Calculate the sha1 hash of a file |
| similar_text() | Calculate the similarity between two strings |
| soundex() | Calculate the soundex key of a string |
| sprintf() | Returns a formatted string |
| sscanf() | Parses input from a string according to a format |
| str_getcsv() | Parse a CSV string into an array |
| str_ireplace() | Replace all occurrences of the search string with the replacement string. Case-insensitive version of str_replace() |
| str_pad() | Pad a string to a certain length with another string |
| str_repeat() | Repeats a string a specified number of times |
| str_replace() | Replace all occurrences of the search string with the replacement string (case-sensitive) |
| str_rot13() | Performs the ROT13 encoding on a string |
| str_shuffle() | Randomly shuffles all characters in a string |
| str_split() | Splits a string into an array |
| str_word_count() | Counts the number of words in a string |
| strcasecmp() | Binary safe comparison of two string (case-insensitive) |
| strchr() | Finds the first occurrence of a string inside another string. Alias of strstr() function |
| strcmp() | Binary safe comparison of two string (case sensitive) |
| strcoll() | Locale based comparison of two string (case sensitive) |
| strcspn() | Returns the number of characters found in a string before any part of some specified characters are found |
| strip_tags() | Strip HTML and PHP tags from a string |
| stripcslashes() | Un-quotes a string quoted with addcslashes() |
| stripos() | Finds the position of the first occurrence of a case-insensitive substring in a string |
| stripslashes() | Un-quotes a quoted string |
| stristr() | Finds the first occurrence of a string inside another string (case-insensitive). Case-insensitive version of strstr() |
| strlen() | Returns the length of a string |
| strnatcasecmp() | Compares two strings using a "natural order" algorithm (case-insensitive) |
| strnatcmp() | Compares two strings using a "natural order" algorithm (case-sensitive) |
| strncasecmp() | Binary safe string comparison of the first n characters (case-insensitive) |
| strncmp() | Binary safe string comparison of the first n characters (case-sensitive) |
| strpbrk() | Searches a string for any of a set of characters |
| strpos() | Finds the position of the first occurrence of a substring in a string |
| strrchr() | Finds the last occurrence of a character in a string |
| strrev() | Reverses a string |
| strripos() | Finds the position of the last occurrence of a string inside another string (case-insensitive) |
| strrpos() | Finds the position of the last occurrence of a string inside another string (case-sensitive) |
| strspn() | Returns the number of characters found in a string that contains only characters from a specified charlist |
| strstr() | Finds the first occurrence of a string inside another string (case-sensitive) |
| strtok() | Splits a string into smaller strings |
| strtolower() | Converts a string to lowercase |
| strtoupper() | Converts a string to uppercase |
| strtr() | Translate characters or replace substrings |
| substr() | Returns a part of a string |
| substr_compare() | Compares two strings from a specified start position |
| substr_count() | Counts the number of times a substring occurs in a string |
| substr_replace() | Replaces a part of a string with another string |
| trim() | Removes whitespace (or other characters) from the beginning and end of a string |
| ucfirst() | Converts the first character of a string to uppercase |
| ucwords() | Converts the first character of each word in a string to uppercase |
| vfprintf() | Write a formatted string to a specified output stream |
| vprintf() | Outputs a formatted string |
| vsprintf() | Returns a formatted string |
| wordwrap() | Wraps a string to a given number of characters |