修改CodeSmith中的SchemaExplorer.MySQLSchemaProvider

修改C:\Program Files (x86)\CodeSmith\v6.5\Samples\Projects\CSharp\MySQLSchemaProvider\MySQLSchemaProvider.cs

修改GetCommandParameters方法，原本是没有实现的。一直报错误信息：GetCommandParameters() is not supported in this release.

        /// <summary>

        /// Gets the parameters for a given command.

        /// </summary>

        /// <param name="connectionString">The connection string used to connect to the target database.</param>

        /// <param name="command"></param>

        /// <returns></returns>

        public ParameterSchema[] GetCommandParameters( string connectionString, CommandSchema command )

        {

            // MySQL does not yet implement INFORMATION_SCHEMA.PARAMETERS

            // MySQL Connector/Net 1.0.7 is supposed to support DeriveParameters()

            // However, in my testing there appears to be a bug (throws a NULL reference exception)

            // This method will be unsupported until a subsequent release of DeriverParameters()

            // is working.



            // throw new NotSupportedException( "GetCommandParameters() is not supported in this release." );



            /*

            ArrayList a = new ArrayList();

            ParameterSchema ps;

            DbConnection cnx = null;

            DbCommand cmd = null;

            try

            {

                cnx = new DbConnection(connectionString);



                cmd = new DbCommand(command.Name, cnx);

                cmd.CommandType = CommandType.StoredProcedure;



                cnx.Open();

                IDbCommandBuilder.DeriveParameters(cmd);

                cnx.Close();



                foreach(MySqlParameter param in cmd.Parameters)

                {

                    ps = new ParameterSchema(command, param.ParameterName, param.Direction, param.DbType, 

                        param.MySqlDbType.ToString(), param.Size, param.Precision, param.Scale, param.IsNullable);



                    a.Add(ps);

                }



            }

            catch

            {

                throw;

            }

            finally

            {

                if (cnx != null)

                    cnx.Close();

            }



            return (ParameterSchema[]) a.ToArray(typeof (ParameterSchema));

            */



            string commandText = string.Format("SELECT PARAMETER_NAME, DATA_TYPE, CHARACTER_OCTET_LENGTH, NUMERIC_PRECISION,"

                + " NUMERIC_SCALE, 0 IS_NULLABLE, PARAMETER_MODE"

                + " FROM INFORMATION_SCHEMA.PARAMETERS WHERE SPECIFIC_SCHEMA = '{0}' AND SPECIFIC_NAME = '{1}' AND ROUTINE_TYPE = 'PROCEDURE' ORDER BY ORDINAL_POSITION", command.Database.Name, command.Name);

            List<ParameterSchema> parameterSchema = new List<ParameterSchema>();



            using (DbConnection connection = CreateConnection(connectionString))

            {

                connection.Open();



                DbCommand cmd = connection.CreateCommand();

                cmd.CommandText = commandText;

                cmd.Connection = connection;



                using (IDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection))

                {

                    while (reader.Read())

                    {

                        string name = reader.GetString( 0 );

                        string nativeType = reader.GetString( 1 );

                        long longSize = ( reader.IsDBNull( 2 ) == false ) ? reader.GetInt64( 2 ) : 0;

                        byte precision = ( byte ) ( ( reader.IsDBNull( 3 ) == false ) ? reader.GetInt32( 3 ) : 0 );

                        int scale = ( reader.IsDBNull( 4 ) == false ) ? reader.GetInt32( 4 ) : 0;

                        bool isNullable = ( reader.IsDBNull( 5 ) == false ) && reader.GetBoolean( 5 );

                        string direction = reader.GetString( 6 );

                        ParameterDirection paramDirection = ParameterDirection.Input;

                        switch(direction)

                        {

                            case "IN":

                                paramDirection = ParameterDirection.Input;

                                break;

                            case "OUT":

                                paramDirection = ParameterDirection.Output;

                                break;

                            case "INOUT":

                                paramDirection = ParameterDirection.InputOutput;

                                break;

                            default:

                                paramDirection = ParameterDirection.Input;

                                break;

                        }

                        int size = ( longSize < int.MaxValue ) ? ( int ) longSize : int.MaxValue;



                        bool isUnsigned = ( nativeType.IndexOf( "unsigned" ) > -1 );

                        DbType type = GetDbType( nativeType, isUnsigned );



                        parameterSchema.Add(new ParameterSchema(command,name,paramDirection,type,nativeType,size,precision,scale,isNullable));

                    }



                    if (!reader.IsClosed)

                        reader.Close();

                }



                if (connection.State != ConnectionState.Closed)

                    connection.Close();

            }



            return parameterSchema.ToArray();

        }

编译后生成SchemaExplorer.MySQLSchemaProvider.dll，覆盖程序安装目录中SchemaProviders目录的同名文件。

修改后替换目录(C:\Program Files (x86)\CodeSmith\v6.5\SchemaProviders\SchemaExplorer.MySQLSchemaProvider.dll)中的同名文件。

 

启动CodeSmith后，需要在Schema Explorer中删除原来的MySQL数据库，重新添加，不然会报错。

也可以先卸载GAC中的SchemaExplorer.MySQLSchemaProvider.dll，然后将自己修改、编译并签名后的SchemaExplorer.MySQLSchemaProvider.dll安装到GAC中。