JSON 関数
PHP Manual

json_last_error

(PHP 5 >= 5.3.0)

json_last_errorReturns the last error occured

説明

int json_last_error ( void )

Returns the last error (if any) occured by last JSON parsing.

パラメータ

この関数にはパラメータはありません。

返り値

Returns an integer, the value can be one of the following constants:

JSON error codes
Constant Meaning
JSON_ERROR_NONE No error has occured
JSON_ERROR_DEPTH The maximum stack depth has been exceeded
JSON_ERROR_CTRL_CHAR Control character error, possibly incorrectly encoded
JSON_ERROR_SYNTAX Syntax error

例1 json_last_error() example

<?php
// A valid json string
$json[] = '{"Organization": "PHP Documentation Team"}';

// An invalid json string which will cause an syntax 
// error, in this case we used ' instead of " for quotation
$json[] = "{'Organization': 'PHP Documentation Team'}";


foreach(
$json as $string)
{
    echo 
'Decoding: ' $string;
    
json_decode($string);

    switch(
json_last_error())
    {
        case 
JSON_ERROR_DEPTH:
            echo 
' - Maximum stack depth exceeded';
        break;
        case 
JSON_ERROR_CTRL_CHAR:
            echo 
' - Unexpected control character found';
        break;
        case 
JSON_ERROR_SYNTAX:
            echo 
' - Syntax error, malformed JSON';
        break;
        case 
JSON_ERROR_NONE:
            echo 
' - No errors';
        break;
    }

    echo 
PHP_EOL;
}
?>

上の例の出力は以下となります。

Decoding: {"Organization": "PHP Documentation Team"} - No errors
Decoding: {'Organization': 'PHP Documentation Team'} - Syntax error, malformed JSON

参考


JSON 関数
PHP Manual