Perl

Get the Root of a JSON Document

See more JSON Examples

Demonstrates how to get back to the JSON root object from anywhere in the JSON document. This example uses the following JSON document:

{
  "flower": "tulip",
  "abc":
    {
    "x": [
       { "a" : 1 },
       { "b1" : 100, "b2" : 200 },
       { "c" : 3 }
    ],
    "y": 200,
    "z": 200
    }
}

Perl

use chilkat();

$success = 0;

$json = chilkat::CkJsonObject->new();

$jsonStr = "{\"flower\": \"tulip\",\"abc\":{\"x\": [{ \"a\" : 1 },{ \"b1\" : 100, \"b2\" : 200 },{ \"c\" : 3 }],\"y\": 200,\"z\": 200}}";

$success = $json->Load($jsonStr);
if ($success == 0) {
    print $json->lastErrorText() . "\r\n";
    exit;
}

# Get the "abc" object.
$abcObj = chilkat::CkJsonObject->new();
$success = $json->ObjectOf2("abc",$abcObj);
if ($success == 0) {
    print $json->lastErrorText() . "\r\n";
    exit;
}

# Side note: The JSON of a sub-part of the document can be emitted from any JSON object:
$abcObj->put_EmitCompact(0);
print $abcObj->emit() . "\r\n";

# Navigate to the "x" array
$xArray = chilkat::CkJsonArray->new();
$abcObj->ArrayOf2("x",$xArray);

# Navigate to the 2nd object contained within the array.  This contains members b1 and b2
$bObj = chilkat::CkJsonObject->new();
$xArray->ObjectAt2(1,$bObj);

# Show that we're at "b1/b2".
# The value of "b1" should be "200"
print "b2 = " . $bObj->IntOf("b2") . "\r\n";

# Now go back to the JSON doc root:
$docRoot = chilkat::CkJsonObject->new();
$bObj->GetDocRoot2($docRoot);

# We'll skip the null check and assume it's non-null...

# Pretty-print the JSON doc from the root to show that this is indeed the root.
$docRoot->put_EmitCompact(0);
print $docRoot->emit() . "\r\n";