问题
I am trying to use the Microsoft Bing API.
$data = file_get_contents("http://api.microsofttranslator.com/V2/Ajax.svc/Speak?appId=APPID&text={$text}&language=ja&format=audio/wav");
$data = stripslashes(trim($data));
The data returned has a ' ' character in the first character of the returned string. It is not a space, because I trimed it before returning the data.
The ' ' character turned out to be %EF%BB%BF.
I wonder why this happened, maybe a bug from Microsoft?
How can I remove this %EF%BB%BF in PHP?
回答1:
You could use substr to only get the rest without the UTF-8 BOM:
// if it’s binary UTF-8
$data = substr($data, 3);
// if it’s percent-encoded UTF-8
$data = substr($data, 9);
回答2:
You should not simply discard the BOM unless you're 100% sure that the stream will: (a) always be UTF-8, and (b) always have a UTF-8 BOM.
The reasons:
- In UTF-8, a BOM is optional - so if the service quits sending it at some future point you'll be throwing away the first three characters of your response instead.
- The whole purpose of the BOM is to identify unambiguously the type of UTF stream being interpreted UTF-8? -16? or -32?, and also to indicate the 'endian-ness' (byte order) of the encoded information. If you just throw it away you're assuming that you're always getting UTF-8; this may not be a very good assumption.
- Not all BOMs are 3-bytes long, only the UTF-8 one is three bytes. UTF-16 is two bytes, and UTF-32 is four bytes. So if the service switches to a wider UTF encoding in the future, your code will break.
I think a more appropriate way to handle this would be something like:
/* Detect the encoding, then convert from detected encoding to ASCII */
$enc = mb_detect_encoding($data);
$data = mb_convert_encoding($data, "ASCII", $enc);
回答3:
$data = file_get_contents("http://api.microsofttranslator.com/V2/Ajax.svc/Speak?appId=APPID&text={$text}&language=ja&format=audio/wav");
$data = stripslashes(trim($data));
if (substr($data, 0, 3) == "\xef\xbb\xbf") {
$data = substr($data, 3);
}
回答4:
It's a byte order mark (BOM), indicating the response is encoded as UTF-8. You can safely remove it, but you should parse the remainder as UTF-8.
回答5:
I had the same problem today, and fixed by ensuring the string was set to UTF-8:
http://php.net/manual/en/function.utf8-encode.php
$content = utf8_encode ( $content );
回答6:
To remove it from the beginning of the string (only):
$data = preg_replace('/^%EF%BB%BF/', '', $data);
回答7:
$data = str_replace('%EF%BB%BF', '', $data);
You probably shouldn't be using stripslashes -- unless the API returns blackslashed data (and 99.99% chance it doesn't), take that call out.
来源：https://stackoverflow.com/questions/4057742/how-to-remove-efbbbf-in-a-php-string