PHP interception string functions substr, iconv_substr, mb_substr examples and pros and cons analysis_PHP tutorial

Sample code, using the functions substr and iconv_substr, mb_substr

< ?php
$str='123Script House 456 welcomes everyone';
echo substr($str,0,4);
echo '
';
echo iconv_substr ($str,0,4,'utf-8');
echo '
';
echo mb_substr($str,0,4,'utf-8');
? >

Note:
The above code uses two functions iconv_substr and mb_substr, both of which can intercept strings under the current character to achieve Chinese character interception without garbled characters.

How to choose?

1. The iconv library may not run correctly on some operating systems, and the GNU extension library needs to be installed to ensure its normal operation. The mb_substr function is more compatible.

2. The iconv function will first convert the current string into the corresponding encoding and then intercept it, while the mb function intercepts directly according to the specified encoding (providing safe multi-byte interception), so the interception efficiency of the mb function is higher.

Therefore, the mb_substr function is the most appropriate choice for intercepting Chinese strings.