PHP实现的json类实例
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2023-11-12 10:05:04
本文实例讲述了php实现的json类。分享给大家供大家参考。具体如下：
这里注意json_encode只有(php 5 >= 5.2.0, pecl json &g...
本文实例讲述了php实现的json类。分享给大家供大家参考。具体如下：
这里注意json_encode只有(php 5 >= 5.2.0, pecl json >= 1.2.0)才有
<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
/**
* converts to and from json format.
*
* json (javascript object notation) is a lightweight data-interchange
* format. it is easy for humans to read and write. it is easy for machines
* to parse and generate. it is based on a subset of the javascript
* programming language, standard ecma-262 3rd edition - december 1999.
* this feature can also be found in python. json is a text format that is
* completely language independent but uses conventions that are familiar
* to programmers of the c-family of languages, including c, c++, c#, java,
* javascript, perl, tcl, and many others. these properties make json an
* ideal data-interchange language.
*
* this package provides a simple encoder and decoder for json notation. it
* is intended for use with client-side javascript applications that make
* use of httprequest to perform server communication functions - data can
* be encoded into json notation for use in a client-side javascript, or
* decoded from incoming javascript requests. json format is native to
* javascript, and can be directly eval()'ed with no further parsing
* overhead
*
* all strings should be in ascii or utf-8 format!
*
* license: redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met: redistributions of source code must retain the
* above copyright notice, this list of conditions and the following
* disclaimer. redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
*
* this software is provided ``as is'' and any express or implied
* warranties, including, but not limited to, the implied warranties of
* merchantability and fitness for a particular purpose are disclaimed. in
* no event shall contributors be liable for any direct, indirect,
* incidental, special, exemplary, or consequential damages (including,
* but not limited to, procurement of substitute goods or services; loss
* of use, data, or profits; or business interruption) however caused and
* on any theory of liability, whether in contract, strict liability, or
* tort (including negligence or otherwise) arising in any way out of the
* use of this software, even if advised of the possibility of such
* damage.
*
* @category
* @package services_json
* @author michal migurski <mike-json@teczno.com>
* @author matt knapp <mdknapp[at]gmail[dot]com>
* @author brett stimmerman <brettstimmerman[at]gmail[dot]com>
* @copyright 2005 michal migurski
* @version cvs: $id: json.php,v 1.31 2006/06/28 05:54:17 migurski exp $
* @license http://www.opensource.org/licenses/bsd-license.php
* @link http://pear.php.net/pepr/pepr-proposal-show.php?id=198
*/
/**
* marker constant for services_json::decode(), used to flag stack state
*/
define('services_json_slice', 1);
/**
* marker constant for services_json::decode(), used to flag stack state
*/
define('services_json_in_str', 2);
/**
* marker constant for services_json::decode(), used to flag stack state
*/
define('services_json_in_arr', 3);
/**
* marker constant for services_json::decode(), used to flag stack state
*/
define('services_json_in_obj', 4);
/**
* marker constant for services_json::decode(), used to flag stack state
*/
define('services_json_in_cmt', 5);
/**
* behavior switch for services_json::decode()
*/
define('services_json_loose_type', 16);
/**
* behavior switch for services_json::decode()
*/
define('services_json_suppress_errors', 32);
/**
* converts to and from json format.
*
* brief example of use:
*
* <code>
* // create a new instance of services_json
* $json = new services_json();
*
* // convert a complexe value to json notation, and send it to the browser
* $value = array('foo', 'bar', array(1, 2, 'baz'), array(3, array(4)));
* $output = $json->encode($value);
*
* print($output);
* // prints: ["foo","bar",[1,2,"baz"],[3,[4]]]
*
* // accept incoming post data, assumed to be in json notation
* $input = file_get_contents('php://input', 1000000);
* $value = $json->decode($input);
* </code>
*/
class services_json
{
/**
* constructs a new json instance
*
* @param int $use object behavior flags; combine with boolean-or
*
* possible values:
* - services_json_loose_type: loose typing.
* "{...}" syntax creates associative arrays
* instead of objects in decode().
* - services_json_suppress_errors: error suppression.
* values which can't be encoded (e.g. resources)
* appear as null instead of throwing errors.
* by default, a deeply-nested resource will
* bubble up with an error, so all return values
* from encode() should be checked with iserror()
*/
function services_json($use = 0)
{
$this->use = $use;
}
/**
* convert a string from one utf-16 char to one utf-8 char
*
* normally should be handled by mb_convert_encoding, but
* provides a slower php-only method for installations
* that lack the multibye string extension.
*
* @param string $utf16 utf-16 character
* @return string utf-8 character
* @access private
*/
function utf162utf8($utf16)
{
// oh please oh please oh please oh please oh please
if(function_exists('mb_convert_encoding')) {
return mb_convert_encoding($utf16, 'utf-8', 'utf-16');
}
$bytes = (ord($utf16{0}) << 8) | ord($utf16{1});
switch(true) {
case ((0x7f & $bytes) == $bytes):
// this case should never be reached, because we are in ascii range
// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
return chr(0x7f & $bytes);
case (0x07ff & $bytes) == $bytes:
// return a 2-byte utf-8 character
// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
return chr(0xc0 | (($bytes >> 6) & 0x1f))
. chr(0x80 | ($bytes & 0x3f));
case (0xffff & $bytes) == $bytes:
// return a 3-byte utf-8 character
// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
return chr(0xe0 | (($bytes >> 12) & 0x0f))
. chr(0x80 | (($bytes >> 6) & 0x3f))
. chr(0x80 | ($bytes & 0x3f));
}
// ignoring utf-32 for now, sorry
return '';
}
/**
* convert a string from one utf-8 char to one utf-16 char
*
* normally should be handled by mb_convert_encoding, but
* provides a slower php-only method for installations
* that lack the multibye string extension.
*
* @param string $utf8 utf-8 character
* @return string utf-16 character
* @access private
*/
function utf82utf16($utf8)
{
// oh please oh please oh please oh please oh please
if(function_exists('mb_convert_encoding')) {
return mb_convert_encoding($utf8, 'utf-16', 'utf-8');
}
switch(strlen($utf8)) {
case 1:
// this case should never be reached, because we are in ascii range
// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
return $utf8;
case 2:
// return a utf-16 character from a 2-byte utf-8 char
// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
return chr(0x07 & (ord($utf8{0}) >> 2))
. chr((0xc0 & (ord($utf8{0}) << 6))
| (0x3f & ord($utf8{1})));
case 3:
// return a utf-16 character from a 3-byte utf-8 char
// see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
return chr((0xf0 & (ord($utf8{0}) << 4))
| (0x0f & (ord($utf8{1}) >> 2)))
. chr((0xc0 & (ord($utf8{1}) << 6))
| (0x7f & ord($utf8{2})));
}
// ignoring utf-32 for now, sorry
return '';
}
/**
* encodes an arbitrary variable into json format
*
* @param mixed $var any number, boolean, string, array, or object to be encoded.
* see argument 1 to services_json() above for array-parsing behavior.
* if var is a strng, note that encode() always expects it
* to be in ascii or utf-8 format!
*
* @return mixed json string representation of input var or an error if a problem occurs
* @access public
*/
function encode($var)
{
switch (gettype($var)) {
case 'boolean':
return $var ? 'true' : 'false';
case 'null':
return 'null';
case 'integer':
return (int) $var;
case 'double':
case 'float':
return (float) $var;
case 'string':
// strings are expected to be in ascii or utf-8 format
$ascii = '';
$strlen_var = strlen($var);
/*
* iterate over every character in the string,
* escaping with a slash or encoding to utf-8 where necessary
*/
for ($c = 0; $c < $strlen_var; ++$c) {
$ord_var_c = ord($var{$c});
switch (true) {
case $ord_var_c == 0x08:
$ascii .= '\b';
break;
case $ord_var_c == 0x09:
$ascii .= '\t';
break;
case $ord_var_c == 0x0a:
$ascii .= '\n';
break;
case $ord_var_c == 0x0c:
$ascii .= '\f';
break;
case $ord_var_c == 0x0d:
$ascii .= '\r';
break;
case $ord_var_c == 0x22:
case $ord_var_c == 0x2f:
case $ord_var_c == 0x5c:
// double quote, slash, slosh
$ascii .= '\\'.$var{$c};
break;
case (($ord_var_c >= 0x20) && ($ord_var_c <= 0x7f)):
// characters u-00000000 - u-0000007f (same as ascii)
$ascii .= $var{$c};
break;
case (($ord_var_c & 0xe0) == 0xc0):
// characters u-00000080 - u-000007ff, mask 110xxxxx
// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$char = pack('c*', $ord_var_c, ord($var{$c + 1}));
$c += 1;
$utf16 = $this->utf82utf16($char);
$ascii .= sprintf('\u%04s', bin2hex($utf16));
break;
case (($ord_var_c & 0xf0) == 0xe0):
// characters u-00000800 - u-0000ffff, mask 1110xxxx
// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$char = pack('c*', $ord_var_c,
ord($var{$c + 1}),
ord($var{$c + 2}));
$c += 2;
$utf16 = $this->utf82utf16($char);
$ascii .= sprintf('\u%04s', bin2hex($utf16));
break;
case (($ord_var_c & 0xf8) == 0xf0):
// characters u-00010000 - u-001fffff, mask 11110xxx
// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$char = pack('c*', $ord_var_c,
ord($var{$c + 1}),
ord($var{$c + 2}),
ord($var{$c + 3}));
$c += 3;
$utf16 = $this->utf82utf16($char);
$ascii .= sprintf('\u%04s', bin2hex($utf16));
break;
case (($ord_var_c & 0xfc) == 0xf8):
// characters u-00200000 - u-03ffffff, mask 111110xx
// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$char = pack('c*', $ord_var_c,
ord($var{$c + 1}),
ord($var{$c + 2}),
ord($var{$c + 3}),
ord($var{$c + 4}));
$c += 4;
$utf16 = $this->utf82utf16($char);
$ascii .= sprintf('\u%04s', bin2hex($utf16));
break;
case (($ord_var_c & 0xfe) == 0xfc):
// characters u-04000000 - u-7fffffff, mask 1111110x
// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$char = pack('c*', $ord_var_c,
ord($var{$c + 1}),
ord($var{$c + 2}),
ord($var{$c + 3}),
ord($var{$c + 4}),
ord($var{$c + 5}));
$c += 5;
$utf16 = $this->utf82utf16($char);
$ascii .= sprintf('\u%04s', bin2hex($utf16));
break;
}
}
return '"'.$ascii.'"';
case 'array':
/*
* as per json spec if any array key is not an integer
* we must treat the the whole array as an object. we
* also try to catch a sparsely populated associative
* array with numeric keys here because some js engines
* will create an array with empty indexes up to
* max_index which can cause memory issues and because
* the keys, which may be relevant, will be remapped
* otherwise.
*
* as per the ecma and json specification an object may
* have any string as a property. unfortunately due to
* a hole in the ecma specification if the key is a
* ecma reserved word or starts with a digit the
* parameter is only accessible using ecmascript's
* bracket notation.
*/
// treat as a json object
if (is_array($var) && count($var) && (array_keys($var) !== range(0, sizeof($var) - 1))) {
$properties = array_map(array($this, 'name_value'),
array_keys($var),
array_values($var));
foreach($properties as $property) {
if(services_json::iserror($property)) {
return $property;
}
}
return '{' . join(',', $properties) . '}';
}
// treat it like a regular array
$elements = array_map(array($this, 'encode'), $var);
foreach($elements as $element) {
if(services_json::iserror($element)) {
return $element;
}
}
return '[' . join(',', $elements) . ']';
case 'object':
$vars = get_object_vars($var);
$properties = array_map(array($this, 'name_value'),
array_keys($vars),
array_values($vars));
foreach($properties as $property) {
if(services_json::iserror($property)) {
return $property;
}
}
return '{' . join(',', $properties) . '}';
default:
return ($this->use & services_json_suppress_errors)
? 'null'
: new services_json_error(gettype($var)." can not be encoded as json string");
}
}
/**
* array-walking function for use in generating json-formatted name-value pairs
*
* @param string $name name of key to use
* @param mixed $value reference to an array element to be encoded
*
* @return string json-formatted name-value pair, like '"name":value'
* @access private
*/
function name_value($name, $value)
{
$encoded_value = $this->encode($value);
if(services_json::iserror($encoded_value)) {
return $encoded_value;
}
return $this->encode(strval($name)) . ':' . $encoded_value;
}
/**
* reduce a string by removing leading and trailing comments and whitespace
*
* @param $str string string value to strip of comments and whitespace
*
* @return string string value stripped of comments and whitespace
* @access private
*/
function reduce_string($str)
{
$str = preg_replace(array(
// eliminate single line comments in '// ...' form
'#^\s*//(.+)$#m',
// eliminate multi-line comments in '/* ... */' form, at start of string
'#^\s*/\*(.+)\*/#us',
// eliminate multi-line comments in '/* ... */' form, at end of string
'#/\*(.+)\*/\s*$#us'
), '', $str);
// eliminate extraneous space
return trim($str);
}
/**
* decodes a json string into appropriate variable
*
* @param string $str json-formatted string
*
* @return mixed number, boolean, string, array, or object
* corresponding to given json input string.
* see argument 1 to services_json() above for object-output behavior.
* note that decode() always returns strings
* in ascii or utf-8 format!
* @access public
*/
function decode($str)
{
$str = $this->reduce_string($str);
switch (strtolower($str)) {
case 'true':
return true;
case 'false':
return false;
case 'null':
return null;
default:
$m = array();
if (is_numeric($str)) {
// lookie-loo, it's a number
// this would work on its own, but i'm trying to be
// good about returning integers where appropriate:
// return (float)$str;
// return float or int, as appropriate
return ((float)$str == (integer)$str)
? (integer)$str
: (float)$str;
} elseif (preg_match('/^("|\').*(\1)$/s', $str, $m) && $m[1] == $m[2]) {
// strings returned in utf-8 format
$delim = substr($str, 0, 1);
$chrs = substr($str, 1, -1);
$utf8 = '';
$strlen_chrs = strlen($chrs);
for ($c = 0; $c < $strlen_chrs; ++$c) {
$substr_chrs_c_2 = substr($chrs, $c, 2);
$ord_chrs_c = ord($chrs{$c});
switch (true) {
case $substr_chrs_c_2 == '\b':
$utf8 .= chr(0x08);
++$c;
break;
case $substr_chrs_c_2 == '\t':
$utf8 .= chr(0x09);
++$c;
break;
case $substr_chrs_c_2 == '\n':
$utf8 .= chr(0x0a);
++$c;
break;
case $substr_chrs_c_2 == '\f':
$utf8 .= chr(0x0c);
++$c;
break;
case $substr_chrs_c_2 == '\r':
$utf8 .= chr(0x0d);
++$c;
break;
case $substr_chrs_c_2 == '\\"':
case $substr_chrs_c_2 == '\\\'':
case $substr_chrs_c_2 == '\\\\':
case $substr_chrs_c_2 == '\\/':
if (($delim == '"' && $substr_chrs_c_2 != '\\\'') ||
($delim == "'" && $substr_chrs_c_2 != '\\"')) {
$utf8 .= $chrs{++$c};
}
break;
case preg_match('/\\\u[0-9a-f]{4}/i', substr($chrs, $c, 6)):
// single, escaped unicode character
$utf16 = chr(hexdec(substr($chrs, ($c + 2), 2)))
. chr(hexdec(substr($chrs, ($c + 4), 2)));
$utf8 .= $this->utf162utf8($utf16);
$c += 5;
break;
case ($ord_chrs_c >= 0x20) && ($ord_chrs_c <= 0x7f):
$utf8 .= $chrs{$c};
break;
case ($ord_chrs_c & 0xe0) == 0xc0:
// characters u-00000080 - u-000007ff, mask 110xxxxx
//see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$utf8 .= substr($chrs, $c, 2);
++$c;
break;
case ($ord_chrs_c & 0xf0) == 0xe0:
// characters u-00000800 - u-0000ffff, mask 1110xxxx
// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$utf8 .= substr($chrs, $c, 3);
$c += 2;
break;
case ($ord_chrs_c & 0xf8) == 0xf0:
// characters u-00010000 - u-001fffff, mask 11110xxx
// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$utf8 .= substr($chrs, $c, 4);
$c += 3;
break;
case ($ord_chrs_c & 0xfc) == 0xf8:
// characters u-00200000 - u-03ffffff, mask 111110xx
// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$utf8 .= substr($chrs, $c, 5);
$c += 4;
break;
case ($ord_chrs_c & 0xfe) == 0xfc:
// characters u-04000000 - u-7fffffff, mask 1111110x
// see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
$utf8 .= substr($chrs, $c, 6);
$c += 5;
break;
}
}
return $utf8;
} elseif (preg_match('/^\[.*\]$/s', $str) || preg_match('/^\{.*\}$/s', $str)) {
// array, or object notation
if ($str{0} == '[') {
$stk = array(services_json_in_arr);
$arr = array();
} else {
if ($this->use & services_json_loose_type) {
$stk = array(services_json_in_obj);
$obj = array();
} else {
$stk = array(services_json_in_obj);
$obj = new stdclass();
}
}
array_push($stk, array('what' => services_json_slice,
'where' => 0,
'delim' => false));
$chrs = substr($str, 1, -1);
$chrs = $this->reduce_string($chrs);
if ($chrs == '') {
if (reset($stk) == services_json_in_arr) {
return $arr;
} else {
return $obj;
}
}
//print("\nparsing {$chrs}\n");
$strlen_chrs = strlen($chrs);
for ($c = 0; $c <= $strlen_chrs; ++$c) {
$top = end($stk);
$substr_chrs_c_2 = substr($chrs, $c, 2);
if (($c == $strlen_chrs) || (($chrs{$c} == ',') && ($top['what'] == services_json_slice))) {
// found a comma that is not inside a string, array, etc.,
// or we've reached the end of the character list
$slice = substr($chrs, $top['where'], ($c - $top['where']));
array_push($stk, array('what' => services_json_slice, 'where' => ($c + 1), 'delim' => false));
//print("found split at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");
if (reset($stk) == services_json_in_arr) {
// we are in an array, so just push an element onto the stack
array_push($arr, $this->decode($slice));
} elseif (reset($stk) == services_json_in_obj) {
// we are in an object, so figure
// out the property name and set an
// element in an associative array,
// for now
$parts = array();
if (preg_match('/^\s*(["\'].*[^\\\]["\'])\s*:\s*(\s.*),?$/uis', $slice, $parts)) {
// "name":value pair
$key = $this->decode($parts[1]);
$val = $this->decode($parts[2]);
if ($this->use & services_json_loose_type) {
$obj[$key] = $val;
} else {
$obj->$key = $val;
}
} elseif (preg_match('/^\s*(\w+)\s*:\s*(\s.*),?$/uis', $slice, $parts)) {
// name:value pair, where name is unquoted
$key = $parts[1];
$val = $this->decode($parts[2]);
if ($this->use & services_json_loose_type) {
$obj[$key] = $val;
} else {
$obj->$key = $val;
}
}
}
} elseif ((($chrs{$c} == '"') || ($chrs{$c} == "'")) && ($top['what'] != services_json_in_str)) {
// found a quote, and we are not inside a string
array_push($stk, array('what' => services_json_in_str, 'where' => $c, 'delim' => $chrs{$c}));
//print("found start of string at {$c}\n");
} elseif (($chrs{$c} == $top['delim']) &&
($top['what'] == services_json_in_str) &&
((strlen(substr($chrs, 0, $c)) - strlen(rtrim(substr($chrs, 0, $c), '\\'))) % 2 != 1)) {
// found a quote, we're in a string, and it's not escaped
// we know that it's not escaped becase there is _not_ an
// odd number of backslashes at the end of the string so far
array_pop($stk);
//print("found end of string at {$c}: ".substr($chrs, $top['where'], (1 + 1 + $c - $top['where']))."\n");
} elseif (($chrs{$c} == '[') &&
in_array($top['what'], array(services_json_slice, services_json_in_arr, services_json_in_obj))) {
// found a left-bracket, and we are in an array, object, or slice
array_push($stk, array('what' => services_json_in_arr, 'where' => $c, 'delim' => false));
//print("found start of array at {$c}\n");
} elseif (($chrs{$c} == ']') && ($top['what'] == services_json_in_arr)) {
// found a right-bracket, and we're in an array
array_pop($stk);
//print("found end of array at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");
} elseif (($chrs{$c} == '{') &&
in_array($top['what'], array(services_json_slice, services_json_in_arr, services_json_in_obj))) {
// found a left-brace, and we are in an array, object, or slice
array_push($stk, array('what' => services_json_in_obj, 'where' => $c, 'delim' => false));
//print("found start of object at {$c}\n");
} elseif (($chrs{$c} == '}') && ($top['what'] == services_json_in_obj)) {
// found a right-brace, and we're in an object
array_pop($stk);
//print("found end of object at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");
} elseif (($substr_chrs_c_2 == '/*') &&
in_array($top['what'], array(services_json_slice, services_json_in_arr, services_json_in_obj))) {
// found a comment start, and we are in an array, object, or slice
array_push($stk, array('what' => services_json_in_cmt, 'where' => $c, 'delim' => false));
$c++;
//print("found start of comment at {$c}\n");
} elseif (($substr_chrs_c_2 == '*/') && ($top['what'] == services_json_in_cmt)) {
// found a comment end, and we're in one now
array_pop($stk);
$c++;
for ($i = $top['where']; $i <= $c; ++$i)
$chrs = substr_replace($chrs, ' ', $i, 1);
//print("found end of comment at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");
}
}
if (reset($stk) == services_json_in_arr) {
return $arr;
} elseif (reset($stk) == services_json_in_obj) {
return $obj;
}
}
}
}
/**
* @todo ultimately, this should just call pear::iserror()
*/
function iserror($data, $code = null)
{
if (class_exists('pear')) {
return pear::iserror($data, $code);
} elseif (is_object($data) && (get_class($data) == 'services_json_error' || is_subclass_of($data, 'services_json_error'))) {
return true;
}
return false;
}
}
if (class_exists('pear_error')) {
class services_json_error extends pear_error
{
function services_json_error($message = 'unknown error', $code = null, $mode = null, $options = null, $userinfo = null)
{
parent::pear_error($message, $code, $mode, $options, $userinfo);
}
}
} else {
/**
* @todo ultimately, this class shall be descended from pear_error
*/
class services_json_error
{
function services_json_error($message = 'unknown error', $code = null, $mode = null, $options = null, $userinfo = null)
{
}
}
}
?>
希望本文所述对大家的php程序设计有所帮助。