$re = '/((\||(?<!^)\G)[^,|]*),(?=.*\|)/m';
$str = 'div-item-2,4,maintype:social| heading:sdfsdf| social: 1, 2, 3 | table:Social| item:3| align:vertical| style:icon| isactive:1,8,0
div-item-0,4,maintype:menu| heading:Quick, Link| table:Menu | menuid:1| align:vertical| style:icon| isactive:1,0,0
div-item-1,4,maintype:text| heading: Name | title: Learn from here| logo:/photos/20/01.jpg| description: This is some description, so you can stay with us| isactive:1,4,0';
$subst = "$1;";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php