php - 将字符串限制为 256 个字节

Question

我目前有:

$payload = array();
$payload['aps']['badge'] = 1;
$payload['aps']['alert'] = html_entity_decode($title);
$payload['aps']['sound'] = "default";

但是:

The maximum size allowed for a notification payload is 256 bytes; Apple Push Notification Service refuses any notification that exceeds this limit.

$title(主要是英文，特殊字符不多)通常大于 256 个字符。我应该如何检查和限制/删除多余的字符？ strlen？

Answer 1

如果标题大于 256，您可以使用 strlen 检查，或者直接将其剪切。$title = substr($title, 0, 256);