//Quotes: Replace smart double quotes with straight double quotes.
//ANSI version for use with 8-bit regex engines and the Windows code page 1252.
preg_replace('[\x84\x93\x94]', '"', $text);//Quotes: Replace smart double quotes with straight double quotes.
//Unicode version for use with Unicode regex engines.
gsub('[\u201C\u201D\u201E\u201F\u2033\u2036]', '"', $text);//Quotes: Replace smart single quotes and apostrophes with straight single quotes.
//Unicode version for use with Unicode regex engines.
gsub("[\u2018\u2019\u201A\u201B\u2032\u2035]", "'", $text);//Quotes: Replace smart single quotes and apostrophes with straight single quotes.
//ANSI version for use with 8-bit regex engines and the Windows code page 1252.
gsub("[\x82\x91\x92]", "'", $text);//Quotes: Replace straight apostrophes with smart apostrophes
gsub("\b'\b", "?", $text);//Quotes: Replace straight double quotes with smart double quotes.
//ANSI version for use with 8-bit regex engines and the Windows code page 1252.
gsub('\B"\b([^"\x84\x93\x94\r\n]+)\b"\B', '?\1?', $text);//Quotes: Replace straight double quotes with smart double quotes.
//Unicode version for use with Unicode regex engines.
gsub('\B"\b([^"\u201C\u201D\u201E\u201F\u2033\u2036\r\n]+)\b"\B', '?\1?', $text);//Quotes: Replace straight single quotes with smart single quotes.
//Unicode version for use with Unicode regex engines.
gsub("\B'\b([^'\u2018\u2019\u201A\u201B\u2032\u2035\r\n]+)\b'\B", "?\1?", $text);//Quotes: Replace straight single quotes with smart single quotes.
//ANSI version for use with 8-bit regex engines and the Windows code page 1252.
gsub("\B'\b([^'\x82\x91\x92\r\n]+)\b'\B", "?\1?", $text);
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