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<?php $str = "string with dot. And another. Again."; $n = 35; // in your case 100 $pos = strrpos(substr($str,0,$n), "."); If($pos === false) $pos = strlen($str); Echo substr($str,0, $pos+1);
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.34, 8.3.0 - 8.3.35, 8.4.1 - 8.4.26, 8.5.0 - 8.5.11
string with dot. And another.

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28.77 ms | 1137 KiB | 7 Q