PHP Manual: Check if a JSON string is valid

Description

bool simdjson_is_valid(string $json = false, int $depth = 512)

Takes a JSON encoded string and returns true if it is valid.

Parameters

json

The json string being validated.

This function only works with UTF-8 encoded strings.

This function validates inputs which json_decode can decode, provided that they are less than 4 GiB long.

depth

Maximum nesting depth of the structure being validated. The value must be greater than 0, and less than or equal to 2147483647. Callers should use reasonably small values, because larger depths require more buffer space and will increase the recursion depth, unlike the current json_decode implementation.

Return Values

Returns true if json is a valid JSON string, false otherwise.

Errors/Exceptions

If json is longer than 4 GiB, a SimdJsonException is thrown as of PECL simdjson 2.1.0, while previously, a RuntimeException was thrown.

If depth is outside the allowed range, a SimdJsonValueError is thrown as of PECL simdjson 3.0.0, while previously, an error of level E_WARNING was raised.

Examples

Example #1 simdjson_decode examples

<?php
$json = '{"a":1,"b":2,"c":3}';
$invalidJson = '{"a":1,"b":2,"c":';

var_dump(simdjson_is_valid($json));
var_dump(simdjson_is_valid($invalidJson));

?>

The above example will output:

bool(true)
bool(false)

Example #2 depth errors

<?php
// Encode some data with a maximum depth of 4
// (array -> array -> array -> string)
$json = json_encode(
    [
        1 => [
            'English' => [
                'One',
                'January'
            ],
            'French' => [
                'Une',
                'Janvier'
            ]
        ]
    ]
);

// Show the errors for different depths.
var_dump(simdjson_is_valid($json, 4));
var_dump(simdjson_is_valid($json, 3));
?>

The above example will output:

bool(true)
bool(false)

Notes

Note:
The JSON spec is not JavaScript, but a subset of JavaScript.

Note:
In the event of a failure to decode, a SimdJsonException is thrown and SimdJsonException::getCode and SimdJsonException::getMessage can be used to determine the exact nature of the error.

simdjson_is_valid