Com.joybase.DB.dll source Code (4)

Source Code///<summary>
Internal-protected Database connection classes
</summary>
Protected abstract class Provider
{
A static connection interface;
private static System.Data.IDbConnection Conn;
<summary>
Construction method, set to private type, is a reference to prevent invalid external;
</summary>
Protected Provider ()
{
System.Data.IDbCommand x=new System.Data.OleDb.OleDbCommand ();
}
<summary>
Returns the type of database edge connection
</summary>
public static DBType Type
{
Get
{

return provider.m_dbtype;
}
Set
{
Provider.m_dbtype=value;
}
}
private static string m_connectionstring;
private static string M_connectionstringsetname;
<summary>
Database connection string Setting name
</summary>
public static string Connectionsetname
{
Set
{
Provider.m_connectionstringsetname=value;
}
}
<summary>
Database connection string
</summary>
public static string ConnectionString
{
Set
{
Provider.m_connectionstring=value;
}
}
private static DBType M_dbtype;

<summary>
Get Database Connection interface
</summary>
<returns> return a connection </returns>
public static System.Data.IDbConnection Getconn ()
{
String Connstr= "";
try{
System.Threading.Thread.GetDomain (). Unhandledexception+=new Unhandledexceptioneventhandler (throwdbexception);
if (provider.m_connectionstring== "" | | Provider.m_connectionstring==null)
{
if (Provider.m_ConnectionStringSetName.Trim () = "")
{
connstr=system.configuration.configurationsettings.appsettings["Database.connectionstring"];
}
Else
{
Connstr=system.configuration.configurationsettings.appsettings[provider.m_connectionstringsetname];
}

}
Else
{
connstr=provider.m_connectionstring;
}
if (connstr==null| | connstr== "")
{
throw new Joybasedbexception ("The connection string is empty or is a null type, check your connectionstring and connectionsetname for proper setting, or read the instructions.");
}
DBType M_dbtype;//=provider.databasetype;
/*
* Note: We have made some modifications to the previous code, in view of the System.Data.SqlClient connection
* The word "Provider" is not possible in the string, so we judge according to whether there are Provider words
* The connection is based on System.Data.SqlClient or System.Data.OleDB.
Resources
* You can set the ConnectionString property to a single cell. (You cannot specify a Provider property for a SqlConnection object.) ）
*– or –
*
* You can set individual properties (DataSource, Database, UserName, and so on). If you set a single property, the connection string is generated for you.
* Note that storing user names and passwords in the connection string has a security setting. For more information, see Introduction to Ado.net Connection design Tools.
*
*/
if (Connstr.tolower (). IndexOf ("provider") ==-1) provider.type=dbtype.sqlclient;
else Provider.type=dbtype.oledb;
throw new Exception ("here");

if (m_dbtype==dbtype.sqlclient)
{
Conn=new System.Data.SqlClient.SqlConnection (CONNSTR);
}
Else
{
Conn=new System.Data.OleDb.OleDbConnection (CONNSTR);
}
}
catch (Exception e)
{
String reason= "(1) The database connection string is not set, please double-check the connection string \ r \ n (2) The destination database does not exist, or the database is not started or cannot be logged in; \ r \ n (3) The connection string is not set correctly, please write it in the standard connection mode. \ r \ n ";
throw new Joybasedbexception (E.message,reason);
}
Return conn;
}
}
}