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 .= ""; break; case $ord_var_c == 0x09: $ascii .= " "; break; case $ord_var_c == 0x0A: $ascii .= ""; break; case $ord_var_c == 0x0C: $ascii .= "f"; break; case $ord_var_c == 0x0D: $ascii .= ""; 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 == "": $utf8 .= chr(0x08); ++$c; break; case $substr_chrs_c_2 == " ": $utf8 .= chr(0x09); ++$c; break; case $substr_chrs_c_2 == "": $utf8 .= chr(0x0A); ++$c; break; case $substr_chrs_c_2 == "f": $utf8 .= chr(0x0C); ++$c; break; case $substr_chrs_c_2 == "": $utf8 .= chr(0x0D); ++$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 $obj; } } //print("parsing {$chrs}"); $strlen_chrs = strlen($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 - $top["where"])).""); if (reset($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 {$c}"); } elseif (($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 - $top["where"])).""); } elseif (($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}"); } 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 - $top["where"])).""); } elseif (($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}"); } 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 - $top["where"])).""); } elseif (($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}"); } 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 - $top["where"])).""); } } if (reset($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。
