$re = '/\*LogonType="Owner/m';
$str = '1. **LogonType="Owner"** MailboxOwnerUPN="" MailboxOwnerSid="" DestMailboxOwnerUPN="" DestMailboxOwnerSid="" DestMailboxGuid="" CrossMailboxOperation="" LogonUserDisplayName="" LogonUserSid="" SourceItems="" SourceFolders="" SourceItemIdsList="" SourceItemSubjectsList="" SourceItemAttachmentsList="" SourceItemFolderPathNamesList="Inbox" SourceFolderPathNamesList="" ItemId="" ItemSubject="" ItemAttachments="" DirtyProperties="" OriginatingServer="" MailboxGuid="" MailboxResolvedOwnerName="" LastAccessed="" Identity="=" IsValid="True" ObjectState="New"
2. 2019-04-01T00:14:59+02:00 Operation="" OperationResult="" LogonType="Admin" ExternalAccess="False" DestFolderId="" DestFolderPathName="" FolderId="" FolderPathName="" ClientInfoString="Client=POP3/IMAP4;Protocol=IMAP4" ClientIPAddress="" ClientMachineName="" ClientProcessName="" ClientVersion="" **InternalLogonType="Owner"** MailboxOwnerUPN="" MailboxOwnerSid="" DestMailboxOwnerUPN="" DestMailboxOwnerSid="" DestMailboxGuid="" CrossMailboxOperation="" LogonUserDisplayName="" LogonUserSid="" SourceItems="" SourceFolders="" SourceItemIdsList=" SourceItemSubjectsList="" SourceItemAttachmentsList="" SourceItemFolderPathNamesList="Inbox" SourceFolderPathNamesList="" ItemId="" ItemSubject="" ItemAttachments="" DirtyProperties="" OriginatingServer="" MailboxGuid="" MailboxResolvedOwnerName="" LastAccessed="" Identity="" IsValid="True" ObjectState="New"';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
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