There are many methods to detect string encoding in php. The most common method is to directly use the mb_detect_encoding function, but a more advanced method is to use the ascii value of the character to judge it.
Example 1
| The Code is as follows: |
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Function is_utf8 ($ str)
{
$ C = 0; $ B = 0;
$ Bits = 0;
$ Len = strlen ($ str );
For ($ I = 0; $ I <$ len; $ I ++ ){
$ C = ord ($ str [$ I]);
If ($ c & gt; 128 ){
If ($ c> = 254) return false;
Elseif ($ c >=252) $ bits = 6;
Elseif ($ c >=248) $ bits = 5;
Elseif ($ c >= 240) $ bits = 4;
Elseif ($ c> = 224) $ bits = 3;
Elseif ($ c> = 192) $ bits = 2;
Else return false;
If ($ I + $ bits)> $ len) return false;
While ($ bits> 1 ){
$ I ++;
$ B = ord ($ str [$ I]);
If ($ B <128 | $ B> 191) return false;
$ Bits --;
}
}
}
Return true;
} |
1. method 1
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Function mb_is_utf8 ($ string)
{
Return mb_detect_encoding () ($ string, 'utf-8') === 'utf-8'; // newly discovered
} |
2. method 2
| The Code is as follows: |
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Function preg_is_utf8 ($ string)
{
Return preg_match ('/^. * $/U', $ string)> 0; // preg_match ('/^./U', $ string)
} |
