加密函数：string mcrypt_encrypt ( string $cipher , string $key , string $data , string $mode [, string $iv ] )

解密函数：string mcrypt_decrypt ( string $cipher , string $key , string $data , string $mode [, string $iv ] )

#$cipher:算法名称，有些算法名称是在某些平台上不能使用，下面列出这里可用的算法名称MCRYPT_3DES、MCRYPT_ARCFOUR_IV(libmcrypt>2.4.xonly)、MCRYPT_ARCFOUR(libmcrypt>2.4.xonly)、MCRYPT_BLOWFISH、MCRYPT_CAST_128、MCRYPT_CAST_256、MCRYPT_CRYPT、MCRYPT_DES、MCRYPT_DES_COMPAT(libmcrypt2.2.xonly)、MCRYPT_ENIGMA(libmcrypt>2.4.xonly,aliasforMCRYPT_CRYPT)、MCRYPT_GOST、MCRYPT_IDEA(non-free)、MCRYPT_LOKI97(libmcrypt>2.4.xonly)、MCRYPT_MARS(libmcrypt>2.4.xonly,non-free)、MCRYPT_PANAMA(libmcrypt>2.4.xonly)、MCRYPT_RIJNDAEL_128(libmcrypt>2.4.xonly)、MCRYPT_RIJNDAEL_192(libmcrypt>2.4.xonly)、MCRYPT_RIJNDAEL_256(libmcrypt>2.4.xonly)、MCRYPT_RC2、MCRYPT_RC4(libmcrypt2.2.xonly)、MCRYPT_RC6(libmcrypt>2.4.xonly)、MCRYPT_RC6_128(libmcrypt2.2.xonly)、MCRYPT_RC6_192(libmcrypt2.2.xonly)、MCRYPT_RC6_256(libmcrypt2.2.xonly)、MCRYPT_SAFER64、MCRYPT_SAFER128、MCRYPT_SAFERPLUS(libmcrypt>2.4.xonly)、MCRYPT_SERPENT(libmcrypt>2.4.xonly)、MCRYPT_SERPENT_128(libmcrypt2.2.xonly)、MCRYPT_SERPENT_192(libmcrypt2.2.xonly)、MCRYPT_SERPENT_256(libmcrypt2.2.xonly)、MCRYPT_SKIPJACK(libmcrypt>2.4.xonly)、MCRYPT_TEAN(libmcrypt2.2.xonly)、MCRYPT_THREEWAY、MCRYPT_TRIPLEDES(libmcrypt>2.4.xonly)、MCRYPT_TWOFISH(foroldermcrypt2.xversions,ormcrypt>2.4.x)、MCRYPT_TWOFISH192、MCRYPT_TWOFISH256、MCRYPT_WAKE(libmcrypt>2.4.xonly)、MCRYPT_XTEA(libmcrypt>2.4.xonly)

#$key:加密时的密钥，不要超过当前算法所支持的最大的密钥长度

#$data:需要加密的数据

#$mode:加密的模式，MCRYPT_MODE_ECB、MCRYPT_MODE_CBC、MCRYPT_MODE_CFB、MCRYPT_MODE_OFBMCRYPT_MODE_NOFB、MCRYPT_MODE_STREAM

使用方法：

<?php$size=mcrypt_get_key_size(MCRYPT_DES,MCRYPT_MODE_ECB);$key=substr(md5('RARONE'),0,$size);$encode=mcrypt_encrypt(MCRYPT_DES,$key,'Cherish',MCRYPT_MODE_ECB);echo$encode,PHP_EOL;--对Cherish加密后的数据echomcrypt_decrypt(MCRYPT_DES,$key,$encode,MCRYPT_MODE_ECB);--解密后的结果