


Why Do Special Characters Appear as Black Diamonds with a Question Mark in PHP?
Nov 08, 2024 am 11:48 AMPHP Character Encoding Issue: Little Black Diamonds with a Question Mark
Users frequently encounter a peculiar issue when retrieving data from a database using PHP: special characters such as quotes appear as black diamonds with a question mark (?). This problem arises from discrepancies between the data's encoding and the encoding used to display it.
To resolve this issue, you can implement various approaches:
- HTTP Header: Add an HTTP header to specify the correct character encoding for the browser:
header("Content-Type: text/html; charset=ISO-8859-1");
- Meta Tag: Include a meta tag in the HTML document to declare the encoding:
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
- Database Connection: Consider retrieving data from the database using a different character encoding, such as UTF-8.
- Iconv Conversion: Utilize the iconv() function to convert the retrieved text to the desired encoding:
$converted = iconv("ISO-8859-1", "UTF-8", $text);
Understanding the underlying encoding issue is crucial. Typically, the data is encoded in a single-byte format like ISO-8859-1 (Latin-1) but is incorrectly interpreted in a unicode encoding (UTF-8 or UTF-16).
The above is the detailed content of Why Do Special Characters Appear as Black Diamonds with a Question Mark in PHP?. For more information, please follow other related articles on the PHP Chinese website!

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