About this PHP code encryption (character encryption), principles and details?

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"Xx.php"

  {$ ' x ' ›«â¾‡ ();} Eval ($²´ööâ†ëš (' D¢¢ìšš ' dš¬àš¨¨þ8 ' òà/æøâ¤î°°øøc¬œø¨¢ðød¢œè´¢îè–¨¤ªš¨¬4¤að²˜abæèdªî= '));! $...ìëô Ó¬áøäå ($⨬òôæì ($¸ñ ôõóå‹ ($¿¯ò¹...œ,$è°ô»¼»ö¨ (' ¦¬²c '), $ ô û篹ù (' ¦¬š= ')), $»œäóê ' óä«($¸ñ ôõóå‹ ($¿¯Ò¹ ... œ,$ðžòµú– (' ¬a== '), $œáó¢åü¿† (' ¦¬²b ')))? $––ö뫾îxœx (): $ó ' ì-˜ÿœ;$›µüâá²úýñùî= $¢ ' â-ùü (' ¦¬²ª¢== '); $šª ' Press ' ü¤ï= $ Íü ' ó† (' ¦¬²b '); $šª ' Press ' ü¤ï= $ëöíëìæååá ($ "Ñž¨´ï˜ ($¸ñ ôõóå‹ ($¿¯ò¹...œ,$›µüâá²úýñùî,$šª ' Press ' ܤï)); return $Šª ' Press ' ü ¤ï;} functionƒˆãý¬ý‡ (&$‰úþ ' ¬ø¤,$òí¦õèôñ¨ä) {$²´ööâ†ëš= $è°ô»¼»ö¨= $ ô û篹ù= $¨ñ¯ ú= $ÐŽòµÚ–= ' ΜÝÀ ' Ñö '; $»¥³ùœî¨¨¥óç= $²´ööâ†ëš (' Œð´œ š¤êœ¢¢š '); $âá ' ôôý¸= $è°ô»¼»ö¨ (' œð´œš¬œ '); $±ÿêå¥= $ ô û篹ù (' AðÐCD¬¬ÊDŠ¬ŒAB²¢ $²«¾¯âì¸= $¨ñ¯ ú (' œð´œcö´cd¬¤šd¢a¢ '); $...éîÿüç‹=$¨ñ¯ ú (' a¤àd1ø¬ba== '); $±ç«ßꢹ¹ê= $»¥³Ùœî¨¨¥óÇ ($ Âá ' Ôôý¸ ($²«¾¯âì¸ ($ðžòµú– (' ¦bbžaª´dšžþdªðæœcîîì¤öè°¢¬öâa ' š¤1b䰤¢îèaªªžâªª¨ªœ¤ "œðö˜aø´c¤ðøš°îàªâªbš°öðcª¤ª+a ¤²šž1´¦00žbî ' bôþž¬œ ' ⬜œža0è°ö´à¤1¬êš¢¢¦a¤¬aœœbðø¢baæšaî "¤¤bàœ¢¬²¬ø4ꪜœ¨°¬îœ¨¢ada0ªš¬1š¤âøa°š¨î°žö¬žø "ª¦î" ¤b5¨¬1蚬îadž¢š¤¢¬¢°01¨ª¤æaab8b¢1¬êšªªœ¬´²¬ðø¢¤0èd¤îaœ¤œ´¨1œšš¤ö= '))); $ïô¬ˆçíøô= $...éîÿüç‹ (', ', $±ç«ßꢹ¹ê); $‰úþ ' ¬ø¤= $ïô¬ˆçíøô[$òí¦õèôñ¨ä];} Functionç '  ¡˜þÿþë () {$œ¼óõš½÷= ' 6f6e66723634 '; $ãþèôëxùë= ' pa '; $šíœ«¨à= ' 7374725f '; $ ÷缫¼= ' H '. ' * '; $ãþèôëxùë.= ' ck '; $œ¼óõš½÷.= ' 5f717270627172 '; $šíœ«¨à.= ' 726f743133 '; $...塵ð ì§ýõ= $ãþèôëxùë ($·÷Ǽ«¼, $šíœ«·¨à); $ ãä  "åð¼ââ= $...塵ð ì§ýõ ($ãþèôëxùë ($ ÷缫¼, $œ¼óõš½÷)); return $ãä " Åð¼ââ;} Functionµýà ' Ñö ($˜³ê˜½þ¾û†,$îíꢿæãï¦= ') {$ç '  ¡˜þÿþë=ç '  ¡˜þÿþë (); $óûûÿªí‹ ã= $ç '  ¡˜þÿþë (' b3jk '); $°ì½áˆ»ò½= $ç '  ¡˜þÿþë (' C3rybgvu ');$ãä  "åð¼ââ= $ç '  ¡˜þÿþë (' Y2hy '); $ÎÍꢿ æãï¦=!$îíꢿæãï¦? $óûûÿªí‹ à (' Ɋ '): $îíꢿæãï¦;$éþ¼x¦ä= $ôñ¿ï˜«ë¢«;for (; $éþ¼x¦ä< $°ì½áˆ»ò½ ($˜³ê˜½þ¾û†); $éþ¼x¦ä++) $‡š "ïè⻤.= $óûûÿªí‹ à ($˜³ê˜½þ¾û†{$éþ¼x¦ä}) <$óûûÿªí‹ à (' Õ ')? (($óûûÿªí‹ à ($˜³ê˜½þ¾û†{$éþ¼x¦ä}) >$ÎÍꢿÆÃϦ&& $óûûÿªí‹ à ($˜³ê˜½þ¾û†{               $éþ¼x¦ä}) <$óûûÿªí‹ à (' Õ '))?$ãä  "Åð¼ââ ($óûûÿªí‹ à ($˜³ê˜½þ¾û†{$éþ¼x¦ä})/2): $˜³ê˜½þ¾û†{$éþ¼x¦ä}): "; $šª ' Press ' ü¤ï= $ç '  ¡˜þÿþë ($‡š" ïè⻤); $»œäóê ' óä«= $ç '  ¡˜þÿþë (' bWQ1 '); $éþ¼x¦ä= $ôñ¿ï˜«ë¢«;$îíꢿæãï¦= $»œäóê ' óä«(' 8_q.l2 '); $óûûÿªí‹ ã= $ctrmax = $°ì½áˆ»ò½ ($îíꢿæãï¦); for ($éþ¼x¦ä< $°ì½áˆ»ò½ ($šª ' Press ' ܤï); $éþ¼x¦ä++) {$óûûÿªí‹ ã= $óûûÿªí‹ Ã? $óûûÿªí‹ Ã: $ctrmax; $óûûÿªí‹ ã--;$½œùž½‰‹ðþâà.= $šª ' Press ' ü¤ï[$éþ¼x¦ä] ^ $îíꢿæãï¦[$óûûÿªí‹ Ã];} return $½œùž½‰‹ðþâà;}}} Global $žåœõêïäÿ«¿, $¾¡ìèü盼ö,$¸ñ ôõóå‹,$ "Ûòú"-÷ð,$碢òüæ,$-±èö¤¡ò,$àíñýö¦œ÷,$åë°îî,$¸öí²üçåžîê,$æàóù‹¥¢ Áûüð,$æ ªµã,$...ìëô Ó¬áøäå,$ð ' û˜ê–,$ëöíëìæååá,$»œäóê ' óä«,$«ž ' ä,$¤¨ïÿæøôø´àà;$‹ª ' ÿùäýº¿º= $šð± ¡¶åõ= $ö¿...¤å¼= $¿' ðàíã...=$æ¹ï°ïû½¡µõ= $ îøóüöµüèãäœ= $ªû÷ñ¼¥òù= $ý£ ûÿ= $£ ' Ñ÷ "æò–¼= $§ª ó¡‡ž= $ž»üæûã= $¨øƒ³ü¦ãìó= $¢ˆãüâï= $šëûâ½ò= $Í䲫û¿ÆÉ = $–¤ê½êï= $†š ' ãºæ¯˜îñ¹= $˜õì¡è¦ ' †÷= ' ƒˆãý¬ý‡ '; if (!$žåœõêïäÿ«¿) {$‹ª ' ÿùäýº¿º ($žåœõêïäÿ«¿, 7); $šð± ¡¶åõ ($¸ñ ôõóå‹,8); $ö¿...¤å¼ ($-±èö¤¡ò,9); $¿' Ðàíã ... ($æàóù‹¥¢áûüð,4); $æ¹ï°ïû½¡µõ ($æ ªµã,12); $îøóüöµüèãäœ ($...ìëô ó¬áøäå,11); $ªû÷ñ¼¥òù ($ð ' û˜ê–,2); $ý£ ûÿ ($ëöíëìæååá, 13); $£ ' Ñ÷ "Æò–¼ ($»œäóê ' óä«,14); $§ª ó¡‡ž ($«ž ' Ä,15); $ Ž»üæûã ($¤¨ïÿæøôø´àà, 16); $¨øƒ³ü¦ãìó ($åë°îî, 17); $¢ˆãüâï ($¸öí²üçåžîê, 18); $šëûâ½ò ($àíñýö¦œ÷, 10); $í䲫û¿æé ($Ç¢¢òüæ, 5); $–¤ê½êï ($ "ûòú"-÷ð,6) $†š ' ãºæ¯˜îñ¹ ($¾¡ìèü盼ö,1); $˜õì¡è¦ ' †÷ ($¶£ýçõ姡ð, 3);} $²´ööâ†ëš= $è°ô»¼»ö¨= $ ô û篹ù= $¨ñ¯ ú= ' µýà ' ñö '; $é "Úö" äç= $²´ööâ†ëš (' žî¤þ '); $šª ' Press ' ü¤ï=òõî¡ ' ¶ ($$É "Úö" ÄÇ); $« Z ' $¤¨ïÿæøôø´àà ($$é "Úö" Äç), $íçõ¥åëèx›¡õ= $¸öí²üçåžîê ($šª ' Press ' ܤï); $½œùž½‰‹ðþâà= $²´ööâ†ëš (' a¤¤dð5¨aš´¦ª1š8a¢´¢1 "¢ž¤òà8žž°0œ395âìcøš9œ¢=="); $½œùž½‰‹ðþâà= $åë°îî ($è°ô»¼»ö¨ (' ¦îažª1b¦ªðঠ'), $½œùž½‰‹ðþâà,$ ô û篹ù (' BØšB¬ªD ')); $ «ž ' $¤¨ïÿæøôø´àà ($$é "Úö" Äç); return $½œùž½‰‹ðþâà;//end?>1œ¬šað¬3œî椞ðøì1 "–¬šœ¤¢öb䦚´œš¢¢ê¢è˜úê9ü¬ Ôœdæ7²°5ô9â+øècêìöª°œbæžœîþšdœîcšîèì ¤¬œžªbž¢¤î° bæ ' ¤¬ "¤ªðøê–úðôæèðœ¤î¢¤š4" C¬Î¤ŽB0¬¦ðªB01Īª8¦ Žbœš¨dæ4œ¤²¬šöš¬š05dò6 œ0470²/' î ô²ðäòö0´ž˜3êâìdœ¦3üè–àüþäþ64˜¢øþâê ' ê7ì4 44š˜ü '  ¤ä ' ÄÈ2 "D¬¬" ¬ Dð0ìda4a¦ø朜œbbabèbð+˜0æ7°ô²ä¨ì7ccâä°°àäô¤ò "Êž7ìžb97žôâêžì˜+d+ê6a6´ ' ¨î48šö¢°œð" °ªœ¬C25äŽ2ØÞCŒ0–DÎ "A¬Šª=Å2ؤ¦B ¢9¦b1´¬ª¢´°bîšœbœbªªîþ¬ø ' Dbøèa¬¬¤b15è;

Don't worry, it can perform normally, without vainly disobey sense:

Thank you very much for Eechen,sanix's enthusiastic reply; it's clear that using compression or other coding makes the code difficult to read.

Updated under: Reference 1, reference 2;
For this kind of PHP obfuscation encryption, crack is not impossible, the most important thing is to understand the program running logic, no need to crack it? As for the online free obfuscation encryption, it is best not to use , their own casually write a safe point, the most confusing is to increase the number of others to spy on your code is difficult, not to peep you.

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Find this code when you are studying a program

"Xx.php"

  {$ ' x ' ›«â¾‡ ();} Eval ($²´ööâ†ëš (' D¢¢ìšš ' dš¬àš¨¨þ8 ' òà/æøâ¤î°°øøc¬œø¨¢ðød¢œè´¢îè–¨¤ªš¨¬4¤að²˜abæèdªî= '));! $...ìëô Ó¬áøäå ($⨬òôæì ($¸ñ ôõóå‹ ($¿¯ò¹...œ,$è°ô»¼»ö¨ (' ¦¬²c '), $ ô û篹ù (' ¦¬š= ')), $»œäóê ' óä«($¸ñ ôõóå‹ ($¿¯Ò¹ ... œ,$ðžòµú– (' ¬a== '), $œáó¢åü¿† (' ¦¬²b ')))? $––ö뫾îxœx (): $ó ' ì-˜ÿœ;$›µüâá²úýñùî= $¢ ' â-ùü (' ¦¬²ª¢== '); $šª ' Press ' ü¤ï= $ Íü ' ó† (' ¦¬²b '); $šª ' Press ' ü¤ï= $ëöíëìæååá ($ "Ñž¨´ï˜ ($¸ñ ôõóå‹ ($¿¯ò¹...œ,$›µüâá²úýñùî,$šª ' Press ' ܤï)); return $Šª ' Press ' ü ¤ï;} functionƒˆãý¬ý‡ (&$‰úþ ' ¬ø¤,$òí¦õèôñ¨ä) {$²´ööâ†ëš= $è°ô»¼»ö¨= $ ô û篹ù= $¨ñ¯ ú= $ÐŽòµÚ–= ' ΜÝÀ ' Ñö '; $»¥³ùœî¨¨¥óç= $²´ööâ†ëš (' Œð´œ š¤êœ¢¢š '); $âá ' ôôý¸= $è°ô»¼»ö¨ (' œð´œš¬œ '); $±ÿêå¥= $ ô û篹ù (' AðÐCD¬¬ÊDŠ¬ŒAB²¢ $²«¾¯âì¸= $¨ñ¯ ú (' œð´œcö´cd¬¤šd¢a¢ '); $...éîÿüç‹=$¨ñ¯ ú (' a¤àd1ø¬ba== '); $±ç«ßꢹ¹ê= $»¥³Ùœî¨¨¥óÇ ($ Âá ' Ôôý¸ ($²«¾¯âì¸ ($ðžòµú– (' ¦bbžaª´dšžþdªðæœcîîì¤öè°¢¬öâa ' š¤1b䰤¢îèaªªžâªª¨ªœ¤ "œðö˜aø´c¤ðøš°îàªâªbš°öðcª¤ª+a ¤²šž1´¦00žbî ' bôþž¬œ ' ⬜œža0è°ö´à¤1¬êš¢¢¦a¤¬aœœbðø¢baæšaî "¤¤bàœ¢¬²¬ø4ꪜœ¨°¬îœ¨¢ada0ªš¬1š¤âøa°š¨î°žö¬žø "ª¦î" ¤b5¨¬1蚬îadž¢š¤¢¬¢°01¨ª¤æaab8b¢1¬êšªªœ¬´²¬ðø¢¤0èd¤îaœ¤œ´¨1œšš¤ö= '))); $ïô¬ˆçíøô= $...éîÿüç‹ (', ', $±ç«ßꢹ¹ê); $‰úþ ' ¬ø¤= $ïô¬ˆçíøô[$òí¦õèôñ¨ä];} Functionç '  ¡˜þÿþë () {$œ¼óõš½÷= ' 6f6e66723634 '; $ãþèôëxùë= ' pa '; $šíœ«¨à= ' 7374725f '; $ ÷缫¼= ' H '. ' * '; $ãþèôëxùë.= ' ck '; $œ¼óõš½÷.= ' 5f717270627172 '; $šíœ«¨à.= ' 726f743133 '; $...塵ð ì§ýõ= $ãþèôëxùë ($·÷Ǽ«¼, $šíœ«·¨à); $ ãä  "åð¼ââ= $...塵ð ì§ýõ ($ãþèôëxùë ($ ÷缫¼, $œ¼óõš½÷)); return $ãä " Åð¼ââ;} Functionµýà ' Ñö ($˜³ê˜½þ¾û†,$îíꢿæãï¦= ') {$ç '  ¡˜þÿþë=ç '  ¡˜þÿþë (); $óûûÿªí‹ ã= $ç '  ¡˜þÿþë (' b3jk '); $°ì½áˆ»ò½= $ç '  ¡˜þÿþë (' C3rybgvu ');$ãä  "åð¼ââ= $ç '  ¡˜þÿþë (' Y2hy '); $ÎÍꢿ æãï¦=!$îíꢿæãï¦? $óûûÿªí‹ à (' Ɋ '): $îíꢿæãï¦;$éþ¼x¦ä= $ôñ¿ï˜«ë¢«;for (; $éþ¼x¦ä< $°ì½áˆ»ò½ ($˜³ê˜½þ¾û†); $éþ¼x¦ä++) $‡š "ïè⻤.= $óûûÿªí‹ à ($˜³ê˜½þ¾û†{$éþ¼x¦ä}) <$óûûÿªí‹ à (' Õ ')? (($óûûÿªí‹ à ($˜³ê˜½þ¾û†{$éþ¼x¦ä}) >$ÎÍꢿÆÃϦ&& $óûûÿªí‹ à ($˜³ê˜½þ¾û†{               $éþ¼x¦ä}) <$óûûÿªí‹ à (' Õ '))?$ãä  "Åð¼ââ ($óûûÿªí‹ à ($˜³ê˜½þ¾û†{$éþ¼x¦ä})/2): $˜³ê˜½þ¾û†{$éþ¼x¦ä}): "; $šª ' Press ' ü¤ï= $ç '  ¡˜þÿþë ($‡š" ïè⻤); $»œäóê ' óä«= $ç '  ¡˜þÿþë (' bWQ1 '); $éþ¼x¦ä= $ôñ¿ï˜«ë¢«;$îíꢿæãï¦= $»œäóê ' óä«(' 8_q.l2 '); $óûûÿªí‹ ã= $ctrmax = $°ì½áˆ»ò½ ($îíꢿæãï¦); for ($éþ¼x¦ä< $°ì½áˆ»ò½ ($šª ' Press ' ܤï); $éþ¼x¦ä++) {$óûûÿªí‹ ã= $óûûÿªí‹ Ã? $óûûÿªí‹ Ã: $ctrmax; $óûûÿªí‹ ã--;$½œùž½‰‹ðþâà.= $šª ' Press ' ü¤ï[$éþ¼x¦ä] ^ $îíꢿæãï¦[$óûûÿªí‹ Ã];} return $½œùž½‰‹ðþâà;}}} Global $žåœõêïäÿ«¿, $¾¡ìèü盼ö,$¸ñ ôõóå‹,$ "Ûòú"-÷ð,$碢òüæ,$-±èö¤¡ò,$àíñýö¦œ÷,$åë°îî,$¸öí²üçåžîê,$æàóù‹¥¢ Áûüð,$æ ªµã,$...ìëô Ó¬áøäå,$ð ' û˜ê–,$ëöíëìæååá,$»œäóê ' óä«,$«ž ' ä,$¤¨ïÿæøôø´àà;$‹ª ' ÿùäýº¿º= $šð± ¡¶åõ= $ö¿...¤å¼= $¿' ðàíã...=$æ¹ï°ïû½¡µõ= $ îøóüöµüèãäœ= $ªû÷ñ¼¥òù= $ý£ ûÿ= $£ ' Ñ÷ "æò–¼= $§ª ó¡‡ž= $ž»üæûã= $¨øƒ³ü¦ãìó= $¢ˆãüâï= $šëûâ½ò= $Í䲫û¿ÆÉ = $–¤ê½êï= $†š ' ãºæ¯˜îñ¹= $˜õì¡è¦ ' †÷= ' ƒˆãý¬ý‡ '; if (!$žåœõêïäÿ«¿) {$‹ª ' ÿùäýº¿º ($žåœõêïäÿ«¿, 7); $šð± ¡¶åõ ($¸ñ ôõóå‹,8); $ö¿...¤å¼ ($-±èö¤¡ò,9); $¿' Ðàíã ... ($æàóù‹¥¢áûüð,4); $æ¹ï°ïû½¡µõ ($æ ªµã,12); $îøóüöµüèãäœ ($...ìëô ó¬áøäå,11); $ªû÷ñ¼¥òù ($ð ' û˜ê–,2); $ý£ ûÿ ($ëöíëìæååá, 13); $£ ' Ñ÷ "Æò–¼ ($»œäóê ' óä«,14); $§ª ó¡‡ž ($«ž ' Ä,15); $ Ž»üæûã ($¤¨ïÿæøôø´àà, 16); $¨øƒ³ü¦ãìó ($åë°îî, 17); $¢ˆãüâï ($¸öí²üçåžîê, 18); $šëûâ½ò ($àíñýö¦œ÷, 10); $í䲫û¿æé ($Ç¢¢òüæ, 5); $–¤ê½êï ($ "ûòú"-÷ð,6) $†š ' ãºæ¯˜îñ¹ ($¾¡ìèü盼ö,1); $˜õì¡è¦ ' †÷ ($¶£ýçõ姡ð, 3);} $²´ööâ†ëš= $è°ô»¼»ö¨= $ ô û篹ù= $¨ñ¯ ú= ' µýà ' ñö '; $é "Úö" äç= $²´ööâ†ëš (' žî¤þ '); $šª ' Press ' ü¤ï=òõî¡ ' ¶ ($$É "Úö" ÄÇ); $« Z ' $¤¨ïÿæøôø´àà ($$é "Úö" Äç), $íçõ¥åëèx›¡õ= $¸öí²üçåžîê ($šª ' Press ' ܤï); $½œùž½‰‹ðþâà= $²´ööâ†ëš (' a¤¤dð5¨aš´¦ª1š8a¢´¢1 "¢ž¤òà8žž°0œ395âìcøš9œ¢=="); $½œùž½‰‹ðþâà= $åë°îî ($è°ô»¼»ö¨ (' ¦îažª1b¦ªðঠ'), $½œùž½‰‹ðþâà,$ ô û篹ù (' BØšB¬ªD ')); $ «ž ' $¤¨ïÿæøôø´àà ($$é "Úö" Äç); return $½œùž½‰‹ðþâà;//end?>1œ¬šað¬3œî椞ðøì1 "–¬šœ¤¢öb䦚´œš¢¢ê¢è˜úê9ü¬ Ôœdæ7²°5ô9â+øècêìöª°œbæžœîþšdœîcšîèì ¤¬œžªbž¢¤î° bæ ' ¤¬ "¤ªðøê–úðôæèðœ¤î¢¤š4" C¬Î¤ŽB0¬¦ðªB01Īª8¦ Žbœš¨dæ4œ¤²¬šöš¬š05dò6 œ0470²/' î ô²ðäòö0´ž˜3êâìdœ¦3üè–àüþäþ64˜¢øþâê ' ê7ì4 44š˜ü '  ¤ä ' ÄÈ2 "D¬¬" ¬ Dð0ìda4a¦ø朜œbbabèbð+˜0æ7°ô²ä¨ì7ccâä°°àäô¤ò "Êž7ìžb97žôâêžì˜+d+ê6a6´ ' ¨î48šö¢°œð" °ªœ¬C25äŽ2ØÞCŒ0–DÎ "A¬Šª=Å2ؤ¦B ¢9¦b1´¬ª¢´°bîšœbœbªªîþ¬ø ' Dbøèa¬¬¤b15è;

Don't worry, it can perform normally, without vainly disobey sense:

Thank you very much for Eechen,sanix's enthusiastic reply; it's clear that using compression or other coding makes the code difficult to read.

Updated under: Reference 1, reference 2;
For this kind of PHP obfuscation encryption, crack is not impossible, the most important thing is to understand the program running logic, no need to crack it? As for the online free obfuscation encryption, it is best not to use , their own casually write a safe point, the most confusing is to increase the number of others to spy on your code is difficult, not to peep you.

Eval.
$test = 0;
TestFunc ($test);
You can use eval ("\ $test =0;testfunc (\ $test);");
is to turn the source file into a string and then use eval.
The string can also be encrypted, such as compression. Then unzip it.
$src =zip ("\ $test =0;testfunc (\ $test);");
Eval (Unzip ($SRC)); see it is garbled.

StackOverflow the PHP code you see on the

  
   \n");}echo "Processing $infile to $outfile\n";$data="ob_end_clean();?>";$data.=php_strip_whitespace($infile); //返回删除注释和空格后的PHP源码// compress data$data=gzcompress($data,9);// encode in base64$data=base64_encode($data);// generate output text$out='
   
    ';// write output textfile_put_contents($outfile,$out);

In fact, PHP7 can be used opcache.file_cache export script opcode Implementation of source code protection, but the exported page opcode is platform-related and binding with PHP version, and does not like the bytecode of Java to achieve a more perfect cross-platform.

Code encryption using Eval and Base64 methods is not much to explain, I mainly explain the garbled:

In the PHP source code, in addition to A-Z can be a variable, and later, presumably in the PHP5, Chinese, Japanese can also be a variable.
This principle, Unicode encoding: CHR (254) is a character that can act as a variable name.

With this principle, it is possible to confuse variable names, functions, and class names.

Recommend a cryptographic tool that leverages this principle enphp:http://enphp.djunny.com/

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