How to Build the dbhelper help class through dbproviderfactory

I found a factory-type Database Help class in my blog some time ago. Which of the following experts can't remember clearly? Mark it now.

1. Database Type Enumeration

 
Public EnumDbprovidertype:Byte{Sqlserver, MySQL, SQLite, Oracle, ODBC, oledb, Firebird, PostgreSQL, DB2, Informix, sqlserverce}
 

2. dbproviderfactory factory class

 Public   Class  Providerfactory {  Private   Static Dictionary <dbprovidertype, String > Providerinvariantnames =New Dictionary <dbprovidertype, String > ();  Private   Static Dictionary <dbprovidertype, dbproviderfactory> providerfactoies = New Dictionary <dbprovidertype, dbproviderfactory> ( 20  );  Static  Providerfactory () {providerinvariantnames. Add (dbprovidertype. sqlserver,  "  System. Data. sqlclient "  ); Providerinvariantnames. Add (dbprovidertype. oledb,  "  System. Data. oledb  "  ); Providerinvariantnames. Add (dbprovidertype. ODBC,  "  System. Data. ODBC  "  ); Providerinvariantnames. Add (dbprovidertype. Oracle,  "  Oracle. dataaccess. Client  " ); Providerinvariantnames. Add (dbprovidertype. MySQL,  "  MySQL. Data. mysqlclient  "  ); Providerinvariantnames. Add (dbprovidertype. SQLite,  "  System. Data. SQLite  "  ); Providerinvariantnames. Add (dbprovidertype. Firebird,  "  Firebirdsql. Data. Firebird  "  ); Providerinvariantnames. Add (dbprovidertype. PostgreSQL, "  Npgsql  "  ); Providerinvariantnames. Add (dbprovidertype. DB2,  "  IBM. Data. db2.iseries  "  ); Providerinvariantnames. Add (dbprovidertype. Informix,  "  IBM. Data. Informix  "  ); Providerinvariantnames. Add (dbprovidertype. sqlserverce,  "  System. Data. sqlserverce "  );}  Public   Static   String  Getproviderinvariantname (dbprovidertype providertype ){  Return  Providerinvariantnames [providertype];}  Public   Static  Dbproviderfactory getdbproviderfactory (dbprovidertype providertype ){  If (!Providerfactoies. containskey (providertype) {providerfactoies. Add (providertype, importdbproviderfactory (providertype ));}  Return  Providerfactoies [providertype];}  Private   Static  Dbproviderfactory importdbproviderfactory (dbprovidertype providertype ){  String Providername = Providerinvariantnames [providertype]; dbproviderfactory Factory = Null  ; Try  {Factory = Dbproviderfactories. getfactory (providername );}  Catch  (Argumentexception e) {Factory = Null  ;}  Return  Factory ;}} 

3. database operation help

  Public   Sealed   Class  Dbhelper { Public   String Connectionstring { Get ; Set  ;}  Private  Dbproviderfactory providerfactory;  Public Dbhelper ( String  Connectionstring, dbprovidertype providertype) {connectionstring = Connectionstring; providerfactory =Providerfactory. getdbproviderfactory (providertype );  If (Providerfactory = Null  ){  Throw   New Argumentexception ( "  Can't load dbproviderfactory for given value of providertype  "  );}} * ********* The specific ADO. Net Operation Method is slightly ************ Public   Int Executenonquery (String SQL, ilist <dbparameter> Parameters)  Public Dbdatareader executereader ( String SQL, ilist <dbparameter> Parameters )} 

4. Database Configuration File

<Connectionstrings> <Add name ="Darjuan_ DB"Connectionstring ="Data Source = DARJUAN-PC; database = darjuan_db; user id = ***; Password = ***; Connection Reset = false; timeout = 120; connection lifetime = 120; min pool size = 20; Max pool size = 50"Providername ="System. Data. sqlclient"/> </Connectionstrings>
 

<System. Data> <dbproviderfactories> <Add name = "  ODBC Data Provider  " Invariant = " System. Data. ODBC  " Description = "  . NET Framework data provider for ODBC  " Type = "  System. Data. ODBC. odbcfactory, system. Data, version = 2.0.0.0, culture = neutral, publickeytoken = b77a5c561934e089  " /> <Add name = "  Oledb data provider  " Invariant = "  System. Data. oledb " Description = "  . NET Framework data provider for oledb  " Type = "  System. Data. oledb. oledbfactory, system. Data, version = 2.0.0.0, culture = neutral, publickeytoken = b77a5c561934e089  " /> <Add name = "  Oracleclient data provider  " Invariant = "  System. Data. oracleclient  " Description = "  . NET Framework data provider for Oracle  " Type = "  System. Data. oracleclient. oracleclientfactory, system. Data. oracleclient, version = 2.0.0.0, culture = neutral, publickeytoken = b77a5c561934e089  " /> <Add name = "  Sqlclient data provider  " Invariant = "  System. Data. sqlclient  " Description ="  . NET Framework data provider for sqlserver  " Type = "  System. Data. sqlclient. sqlclientfactory, system. Data, version = 2.0.0.0, culture = neutral, publickeytoken = b77a5c561934e089  " /> <Add name = "  Microsoft SQL Server compact data provider  " Invariant = "  System. Data. sqlserverce.4.0  " Description ="  . NET Framework data provider for Microsoft SQL Server compact  " Type = "  System. Data. sqlserverce. sqlceproviderfactory, system. Data. sqlserverce, version = 4.0.0.0, culture = neutral, publickeytoken = 89845dcd80cc91  " /> <Add name = "  SQLite data provider  " Invariant = "  System. Data. SQLite  " Description ="  . NET Framework data provider for SQLite  " Type = "  System. Data. SQLite. sqlitefactory, system. Data. SQLite  " /> <Add name = "  Informix Data Provider  " Invariant = "  IBM. Data. Informix  " Description = " . NET Framework data provider for Informix  " Type = "  IBM. Data. Informix. ifxfactory, IBM. Data. Informix  " /> <Add name = "  DB2 data provider  " Invariant = "  IBM. Data. db2.iseries  " Description = "  . NET Framework data provider for DB2 iseries " Type = "  IBM. Data. db2.iseries. db2factory, IBM. Data. db2.iseries  " /> <Add name = "  Firebird data provider  " Invariant = "  Firebirdsql. Data. firebirdclient  " Description = "  Firebird  " Type = " Firebirdsql. Data. firebirdclient. firebirdclientfactory, firebirdsql. Data. firebirdclient  " /> <Add name = "  Oracle Data Provider  " Invariant = "  Oracle. dataaccess. Client  " Description = "  . NET Framework data provider for Oracle  " Type = " Oracle. dataaccess. Client. oracleclientfactory, Oracle. dataaccess  " /> <Add name = "  PostgreSQL data provider  " Invariant = "  Npgsql  " Description = "  . NET Framework data provider for PostgreSQL  " Type = "  Npgsql. npgsqlfactory, system. Data " /> </Dbproviderfactories> </system. Data>