note 89908 modified in function.json-encode by ajf

For anyone who would like to encode arrays into JSON, but is using PHP 4, and doesn't want to wrangle PECL around, here is a function I wrote in PHP4 to convert nested arrays into JSON. Note that, because javascript converts JSON data into either nested named objects OR vector arrays, it's quite difficult to represent mixed PHP arrays (arrays with both numerical and associative indexes) well in JSON. This function does something funky if you pass it a mixed array -- see the comments for details. I don't make a claim that this function is by any means complete (for example, it doesn't handle objects) so if you have any improvements, go for it. <?php /** * Converts an associative array of arbitrary depth and dimension into JSON representation. * * NOTE: If you pass in a mixed associative and vector array, it will prefix each numerical * key with "key_". For example array("foo", "bar" => "baz") will be translated into * {"key_0": "foo", "bar": "baz"} but array("foo", "bar") would be translated into [ "foo", "bar" ]. * * @param $array The array to convert. * @return mixed The resulting JSON string, or false if the argument was not an array. * @author Andy Rusterholz */ function array_to_json( $array ){ if( !is_array( $array ) ){ return false; } $associative = count( array_diff( array_keys($array), array_keys( array_keys( $array )) )); if( $associative ){ $construct = array(); foreach( $array as $key => $value ){ // We first copy each key/value pair into a staging array, // formatting each key and value properly as we go. // Format the key: if( is_numeric($key) ){ $key = "key_$key"; } $key = '"'.addslashes($key).'"'; // Format the value: if( is_array( $value )){ $value = array_to_json( $value ); } else if( !is_numeric( $value ) || is_string( $value ) ){ $value = '"'.addslashes($value).'"'; } // Add to staging array: $construct[] = "$key: $value"; } // Then we collapse the staging array into the JSON form: $result = "{ " . implode( ", ", $construct ) . " }"; } else { // If the array is a vector (not associative): $construct = array(); foreach( $array as $value ){ // Format the value: if( is_array( $value )){ $value = array_to_json( $value ); } else if( !is_numeric( $value ) || is_string( $value ) ){ $value = '"'.addslashes($value).'"'; } // Add to staging array: $construct[] = $value; } // Then we collapse the staging array into the JSON form: $result = "[ " . implode( ", ", $construct ) . " ]"; } return $result; } ?> --was-- For anyone who would like to encode arrays into JSON, but is using PHP 4, and doesn't want to wrangle PECL around, here is a function I wrote in PHP4 to convert nested arrays into JSON. Note that, because javascript converts JSON data into either nested named objects OR vector arrays, it's quite difficult to represent mixed PHP arrays (arrays with both numerical and associative indexes) well in JSON. This function does something funky if you pass it a mixed array -- see the comments for details. I don't make a claim that this function is by any means complete (for example, it doesn't handle objects) so if you have any improvements, go for it. <?php /** * Converts an associative array of arbitrary depth and dimension into JSON representation. * * NOTE: If you pass in a mixed associative and vector array, it will prefix each numerical * key with "key_". For example array("foo", "bar" => "baz") will be translated into * {'key_0': 'foo', 'bar': 'baz'} but array("foo", "bar") would be translated into [ 'foo', 'bar' ]. * * @param $array The array to convert. * @return mixed The resulting JSON string, or false if the argument was not an array. * @author Andy Rusterholz */ function array_to_json( $array ){ if( !is_array( $array ) ){ return false; } $associative = count( array_diff( array_keys($array), array_keys( array_keys( $array )) )); if( $associative ){ $construct = array(); foreach( $array as $key => $value ){ // We first copy each key/value pair into a staging array, // formatting each key and value properly as we go. // Format the key: if( is_numeric($key) ){ $key = "key_$key"; } $key = "'".addslashes($key)."'"; // Format the value: if( is_array( $value )){ $value = array_to_json( $value ); } else if( !is_numeric( $value ) || is_string( $value ) ){ $value = "'".addslashes($value)."'"; } // Add to staging array: $construct[] = "$key: $value"; } // Then we collapse the staging array into the JSON form: $result = "{ " . implode( ", ", $construct ) . " }"; } else { // If the array is a vector (not associative): $construct = array(); foreach( $array as $value ){ // Format the value: if( is_array( $value )){ $value = array_to_json( $value ); } else if( !is_numeric( $value ) || is_string( $value ) ){ $value = "'".addslashes($value)."'"; } // Add to staging array: $construct[] = $value; } // Then we collapse the staging array into the JSON form: $result = "[ " . implode( ", ", $construct ) . " ]"; } return $result; } ?> http://php.net/manual/en/function.json-encode.php