What is the function of iconv in PHP?

The iconv function is a built-in PHP function used for converting character encodings. It converts a string from one character encoding to another.

In PHP, different character encodings have different representations, using different character sets. The iconv function can convert between different character encodings, allowing strings to be displayed and processed correctly in different character encoding environments.

The basic syntax of the iconv function is as follows:

string iconv ( string $in_charset , string $out_charset , string $str )

Where $in_charset is the character encoding of the input string, $out_charset is the character encoding of the output string, and $str is the string to be converted.

For example, converting a UTF-8 encoded string to a GBK encoded string:

$str = "你好，世界！";
$str_gbk = iconv("UTF-8", "GBK", $str);
echo $str_gbk; // 输出：浣犲ソ锛屽鏋�

In the example above, the character encoding of the input string $str is UTF-8. It is then converted to the GBK encoding and outputted using the iconv function.

Caution: When using the iconv function, make sure the operating system supports the required character encoding and character set, otherwise there may be garbled or failed conversions.