PetaPoco支持OleDb

修改DBType，增加OleDb。

enum DBType
{
    OleDb,
    SqlServer,
    SqlServerCE,
    MySql,
    PostgreSQL,
    Oracle,
    SQLite
}

修改CommonConstruct，增加if (dbtype.StartsWith("OleDb")) _dbType = DBType.OleDb;

private void CommonConstruct()
{
    if (dbtype.StartsWith("OleDb")) _dbType = DBType.OleDb;
    else if (dbtype.StartsWith("MySql")) _dbType = DBType.MySql;
    else if (dbtype.StartsWith("SqlCe")) _dbType = DBType.SqlServerCE;
    else if (dbtype.StartsWith("Npgsql")) _dbType = DBType.PostgreSQL;
    else if (dbtype.StartsWith("Oracle")) _dbType = DBType.Oracle;
    else if (dbtype.StartsWith("SQLite")) _dbType = DBType.SQLite;
    else if (dbtype.StartsWith("System.Data.SqlClient.")) _dbType = DBType.SqlServer;
}

调用：

Dim db As Database = New Database(cs, "System.Data.OleDb")