oracle处理乱码的问题

先在pl/sql里面查询出oracle客户端的字符集，select userenv('language') from dual;

然后在环境变量设置，这里设置好后一定要重新启动电脑，我尝试了很多方法不重启电脑就是不生效。

  最后在代码里面做设置：

   System.Environment.SetEnvironmentVariable("NLS_LANG", "AMERICAN_AMERICA.ZHS16GBK");

下表是locale ID与字符集名称的对应关系：

Language	Locale ID	NLS_LANG
English (American)	en_US.UTF-8	AMERICAN_AMERICA.AL32UTF8
English (American)	en_US.ISO-8859-1	AMERICAN_AMERICA.WE8ISO8859P1
English (American)	en_US.ISO-8859-15	AMERICAN_AMERICA.WE8ISO8859P15
English (Australian)	en_AU.UTF-8	ENGLISH_AUSTRALIA.AL32UTF8
English (Australian)	en_AU.ISO-8859-1	ENGLISH_AUSTRALIA.WE8ISO8859P1
English (Australian)	en_AU.ISO-8859-15	ENGLISH_AUSTRALIA.WE8ISO8859P15
English (British)	en_GB.UTF-8	ENGLISH_UNITED KINGDOM.AL32UTF8
English (British)	en_GB.ISO-8859-1	ENGLISH_UNITED KINGDOM.WE8ISO8859P1
English (British)	en_GB.ISO-8859-15	ENGLISH_UNITED KINGDOM.WE8ISO8859P15
English (Ireland)	en_IE.UTF-8	ENGLISH_IRELAND.AL32UTF8
English (Ireland)	en_IE.ISO-8859-1	ENGLISH_IRELAND.WE8ISO8859P1
English (Ireland)	en_IE.ISO-8859-15	ENGLISH_IRELAND.WE8ISO8859P15
German	de_DE.UTF-8	GERMAN_GERMANY.AL32UTF8
German	de_DE.ISO-8859-1	GERMAN_GERMANY.WE8ISO8859P1
German	de_DE.ISO-8859-15	GERMAN_GERMANY.WE8ISO8859P15
French	fr_FR.UTF-8	FRENCH_FRANCE.AL32UTF8
French	fr_FR.ISO-8859-1	FRENCH_FRANCE.WE8ISO8859P1
French	fr_FR.ISO-8859-15	FRENCH_FRANCE.WE8ISO8859P15
Italian	it_IT.UTF-8	ITALIAN_ITALY.AL32UTF8
Italian	it_IT.ISO-8859-1	ITALIAN_ITALY.WE8ISO8859P1
Italian	it_IT.ISO-8859-15	ITALIAN_ITALY.WE8ISO8859P15
Spanish	es_ES.UTF-8	SPANISH_SPAIN.AL32UTF8
Spanish	es_ES.ISO-8859-1	SPANISH_SPAIN.WE8ISO8859P1
Spanish	es_ES.ISO-8859-15	SPANISH_SPAIN.WE8ISO8859P15
Spanish (Mexico)	es_MX.UTF-8	MEXICAN SPANISH_MEXICO.AL32UTF8
Spanish (Mexico)	es_MX.ISO-8859-1	MEXICAN SPANISH_MEXICO.WE8ISO8859P1
Spanish (Mexico)	es_MX.ISO-8859-15	MEXICAN SPANISH_MEXICO.WE8ISO8859P15
Portuguese (Brazilian)	pt_BR.UTF-8	BRAZILIAN PORTUGUESE_BRAZIL.AL32UTF8
Portuguese (Brazilian)	pt_BR.ISO-8859-1	BRAZILIAN PORTUGUESE_BRAZIL.WE8ISO8859P1
Portuguese (Brazilian)	pt_BR.ISO-8859-15	BRAZILIAN PORTUGUESE_BRAZIL.WE8ISO8859P15
Japanese	ja_JP.EUC-JP	JAPANESE_JAPAN.JA16EUC
Japanese	ja_JP.UTF-8	JAPANESE_JAPAN.AL32UTF8
Korean	ko_KR.EUC-KR	KOREAN_KOREA.KO16KSC5601
Korean	ko_KR.UTF-8	KOREAN_KOREA.AL32UTF8
Chinese (simplified)	zh_CN.GB18030	SIMPLIFIED CHINESE_CHINA.ZHS32GB18030
Chinese (simplified)	zh_CN.UTF-8	SIMPLIFIED CHINESE_CHINA.AL32UTF8
Chinese (traditional)	zh_TW.BIG5	TRADITIONAL CHINESE_TAIWAN.ZHT16BIG5
Chinese (traditional)	zh_TW.UTF-8	TRADITIONAL CHINESE_TAIWAN