在嵌套IF ELSE（PHP）中使用变量[重复]

Question

This question already has an answer here:

• “Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP 28 answers

I have a problem in using of array as a variable in nested if..else.. conditions. Its used to create custom web-service APIs. Here is the structure of code:

if (condition) {
    // code to be executed in case of true

    if (condition) {
        // code to be executed in case of true

        $result['key1'] = $variable1;
        $result['key2'] = $variable2;
        $result['key3'] = $variable3;

    } else {
        // code to be executed in case of false
    }

} else {
    $result['error'] = 'Something went wrong!!!';
}
echo json_encode($result);    // line 121

On execution of code it displays the following error:

Notice: Undefined variable: result in C:\xampp.. on line 121

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Answer 1

Variables need to be declared before using it inside functions like json_encode()! Do it this way:

$result = array();
if (condition) {
    // code to be executed in case of true

    if (condition) {
        // code to be executed in case of true

        $result['key1'] = $variable1;
        $result['key2'] = $variable2;
        $result['key3'] = $variable3;

    } else {
        // code to be executed in case of false
    }

} else {
    $result['error'] = 'Something went wrong!!!';
}
echo json_encode($result);