# MongoDB\BSON\toCanonicalExtendedJSON

(mongodb >=1.3.0)

MongoDB\BSON\toCanonicalExtendedJSON — Returns the Canonical Extended JSON representation of a BSON value

### 说明

MongoDB\BSON\toCanonicalExtendedJSON ( string `$bson` ) : string

Converts a BSON string to its » Canonical Extended JSON representation. The canonical format prefers type fidelity at the expense of concise output and is most suited for producing output that can be converted back to BSON without any loss of type information (e.g. numeric types will remain differentiated).

### 参数

`bson` (string)

  BSON value to be converted.

### 返回值

The converted JSON value.

### 错误／异常

- Throws MongoDB\Driver\Exception\UnexpectedValueException if the input did not contain exactly one BSON document. Possible reasons include, but are not limited to, invalid BSON, extra data (after reading one BSON document), or an unexpected » libbson error.

### 范例

Example #1 MongoDB\BSON\toCanonicalExtendedJSON() example

    <?php

    $documents = [
        [ 'null' => null ],
        [ 'boolean' => true ],
        [ 'string' => 'foo' ],
        [ 'int32' => 123 ],
        [ 'int64' => 4294967295 ],
        [ 'double' => 1.0, ],
        [ 'nan' => NAN ],
        [ 'pos_inf' => INF ],
        [ 'neg_inf' => -INF ],
        [ 'array' => [ 'foo', 'bar' ]],
        [ 'document' => [ 'foo' => 'bar' ]],
        [ 'oid' => new MongoDB\BSON\ObjectId('56315a7c6118fd1b920270b1') ],
        [ 'dec128' => new MongoDB\BSON\Decimal128('1234.5678') ],
        [ 'binary' => new MongoDB\BSON\Binary('foo', MongoDB\BSON\Binary::TYPE_GENERIC) ],
        [ 'date' => new MongoDB\BSON\UTCDateTime(1445990400000) ],
        [ 'timestamp' => new MongoDB\BSON\Timestamp(1234, 5678) ],
        [ 'regex' => new MongoDB\BSON\Regex('pattern', 'i') ],
        [ 'code' => new MongoDB\BSON\Javascript('function() { return 1; }') ],
        [ 'code_ws' => new MongoDB\BSON\Javascript('function() { return a; }', ['a' => 1]) ],
        [ 'minkey' => new MongoDB\BSON\MinKey ],
        [ 'maxkey' => new MongoDB\BSON\MaxKey ],
    ];

    foreach ($documents as $document) {
        $bson = MongoDB\BSON\fromPHP($document);
        echo MongoDB\BSON\toCanonicalExtendedJSON($bson), "\n";
    }

    ?>

以上例程会输出：

    { "null" : null }
    { "boolean" : true }
    { "string" : "foo" }
    { "int32" : { "$numberInt" : "123" } }
    { "int64" : { "$numberLong" : "4294967295"} }
    { "double" : { "$numberDouble" : "1.0" } }
    { "nan" : { "$numberDouble" : "NaN" } }
    { "pos_inf" : { "$numberDouble" : "Infinity" } }
    { "neg_inf" : { "$numberDouble" : "-Infinity" } }
    { "array" : [ "foo", "bar" ] }
    { "document" : { "foo" : "bar" } }
    { "oid" : { "$oid" : "56315a7c6118fd1b920270b1" } }
    { "dec128" : { "$numberDecimal" : "1234.5678" } }
    { "binary" : { "$binary" : { "base64": "Zm9v", "subType" : "00" } } }
    { "date" : { "$date" : { "$numberLong" : "1445990400000" } } }
    { "timestamp" : { "$timestamp" : { "t" : 5678, "i" : 1234 } } }
    { "regex" : { "$regularExpression" : { "pattern" : "pattern", "options" : "i" } } }
    { "code" : { "$code" : "function() { return 1; }" } }
    { "code_ws" : { "$code" : "function() { return a; }", "$scope" : { "a" : { "$numberInt" : "1" } } } }
    { "minkey" : { "$minKey" : 1 } }
    { "maxkey" : { "$maxKey" : 1 } }

### 参见

- MongoDB\BSON\fromJSON() - Returns the BSON representation of a JSON value
- MongoDB\BSON\toRelaxedExtendedJSON() - Returns the Relaxed Extended JSON representation of a BSON value
- » Extended JSON Specification
- » MongoDB BSON