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1> mixed Parse_url (string $url [, int $component =-1])

Parsing URLs

• $component, specifies the obtained part, does not write, returns an associative array that contains all the URL information specified php_url_scheme, Php_url_host, Php_url_port, Php_url_user, Php_url_pass, One of the Php_url_path, Php_url_query, or php_url_fragment to get a string of the part specified in the URL. (An integer value is returned, except when specified as Php_url_port).

$url = ' Http://username:password@hostname/path?arg=value#anchor ';p rint_r (Parse_url ($url)); Echo Parse_url ($url, PHP _url_path);//output:/path/* output: Array (    [scheme] + HTTP    [host] = hostname    [user] = Username    [ Pass] = password    [path] =/path    [query] = Arg=value    [fragment] = anchor) */

2> void Parse_str (String $str [, Array & $arr])

Resolves multiple variables from a string and can be used in conjunction with the Parse_url function

• $arr, if you set the second variable, arr, the parsed variable will be stored in the array

$url = "http://www.web.com?act=login&id=111"; $query = Parse_url ($url, Php_url_query);p arse_str ($query); Echo $act ;//output: Loginecho $id;//output: 111

3> string Mb_substr (string $str, int $start [, int $length = NULL [, String $encoding = Mb_internal_encoding ()]])

To intercept a string by encoding

• $start, starting Index
• $length, the length of a unit intercepted from an index encoded
• $econding, encoding, and file encoding methods are related

Header (' content-type:text/html; charset=utf-8; '); $STR = "Do not deceive oneself"; Echo mb_substr ($str, 0, 6, ' UTF-8 ');//output: A man can not deceive

4.> mixed Strpos (string $haystack, mixed $needle [, int $offset = 0])

Find where a string first appears

• $haystack, find in the Hanstack string
• $needle, find what character
• $offset, the starting index of the lookup
• Returned, successfully returned the corresponding index position, did not find the return false

$str = ' abcabc '; Echo strpos ($str, ' a ', 1);//output: 3

5> int strlen (string $string)

Gets the length of the string

6> string Strrev (String $string)

Returns the inverted string

7> string substr (string $string, int $start [, int $length])

Intercept string

• Start, start index
• $length, intercept the length, not write The Intercept to the last

  $str = ' a/b.txt '; Echo substr ($str, Strpos ($str, '/') +1); Output: B.txt

8>string strtolower (String $string)

Converts a string to lowercase and returns

String Strtoupper (String $string)

Converts a string to uppercase and returns

9> mixed Str_replace (mixed $search, mixed $replace, mixed $subject [, int & $count])

Replaces some characters in a string, which are case-sensitive. Str_ireplace function ignores case

• $search, the character or string to be replaced
• $replace, replace the heart character or string
• $subject, the replaced object, that is, the total string
• $count, the number of times the substitution occurred

$str = ' a,b,c '; Echo str_replace (', ', ', $str);//output: a b C

10> int strcmp (string $str 1, String $str 2)

Compares strings for equality and is case-sensitive. strcasecmp function ignores case

• If STR1 is less than str2 returns < 0, if STR1 is greater than str2 returns > 0, if both are equal, 0 is returned.

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