防止“注意：数组转换为字符串”[复制]

Question

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• Reference - What does this error mean in PHP? 34 answers

I need help with prevent from "Notice: Array to string conversion in "

$stmt = $DBH->prepare("SELECT * FROM users WHERE id = :emailid");
$stmt->bindParam(':emailid', $emailid, PDO::PARAM_STR);
$stmt->execute();
$result = $stmt->fetchAll();    
foreach($result as $row)
    {
    echo $row['id'].'<br />';
    echo $row['emailid'].'<br />';
    echo $row['password'];
    }

Everythink its OK, index.php?id=5

but when i put index.php?id[]=5

Return me error

Notice: Array to string conversion in 

What is the best way to check for arrays in this case; error_reporting(0) is not a solution I want to find optimized method.

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Answer 1

Not sure in which direction you want this question to go. But let's assume you want - for some reason - make it work either way: ?id=... and ?id[]=...&id[]=...

if ( !is_array($_GET['id']) ) {
    // just make it an array with one element
    $ids = array( $_GET['id'] );
    // so having a simple type string id is just a special case of the 
    // array case
}
else {
    $ids = $_GET['id'];
}

$stmt = $DBH->prepare("SELECT * FROM users WHERE id = :emailid");
$stmt->bindParam(':emailid', $emailid, PDO::PARAM_STR);
foreach( $ids as $emailid ) {
    $stmt->execute();
    $result = $stmt->fetchAll();    
    foreach($result as $row) {
        ...
    }
}