OdbcCommandBuilder.cs source code in C# .NET

                        Code:
                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / Data / System / Data / Odbc / OdbcCommandBuilder.cs / 1305376 / OdbcCommandBuilder.cs
                        
                        
                            //------------------------------------------------------------------------------ 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// [....] 
// [....]
//----------------------------------------------------------------------------- 
 
using System;
using System.Collections; 
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.Common; 
using System.Data.ProviderBase;
using System.Diagnostics; 
using System.Runtime.InteropServices; 
using System.Threading;
using System.Globalization; 
using System.Text;


namespace System.Data.Odbc { 

    public sealed class OdbcCommandBuilder : DbCommandBuilder { 
 
        public OdbcCommandBuilder() : base() {
            GC.SuppressFinalize(this); 
        }

        public OdbcCommandBuilder(OdbcDataAdapter adapter) : this() {
            DataAdapter = adapter; 
        }
 
        [ 
        DefaultValue(null),
        ResCategoryAttribute(Res.DataCategory_Update), 
        ResDescriptionAttribute(Res.OdbcCommandBuilder_DataAdapter), // MDAC 60524
        ]
        new public OdbcDataAdapter DataAdapter {
            get { 
                return (base.DataAdapter as OdbcDataAdapter);
            } 
            set { 
                base.DataAdapter = value;
            } 
        }

        private void OdbcRowUpdatingHandler(object sender, OdbcRowUpdatingEventArgs ruevent) {
            RowUpdatingHandler(ruevent); 
        }
 
        new public OdbcCommand GetInsertCommand() { 
            return (OdbcCommand) base.GetInsertCommand();
        } 
        new public OdbcCommand GetInsertCommand(bool useColumnsForParameterNames) {
            return (OdbcCommand) base.GetInsertCommand(useColumnsForParameterNames);
        }
 
        new public OdbcCommand GetUpdateCommand() {
            return (OdbcCommand) base.GetUpdateCommand(); 
        } 
        new public OdbcCommand GetUpdateCommand(bool useColumnsForParameterNames) {
            return (OdbcCommand) base.GetUpdateCommand(useColumnsForParameterNames); 
        }

        new public OdbcCommand GetDeleteCommand() {
            return (OdbcCommand) base.GetDeleteCommand(); 
        }
        new public OdbcCommand GetDeleteCommand(bool useColumnsForParameterNames) { 
            return (OdbcCommand) base.GetDeleteCommand(useColumnsForParameterNames); 
        }
 
        override protected string GetParameterName(int parameterOrdinal) {
            return "p" + parameterOrdinal.ToString(System.Globalization.CultureInfo.InvariantCulture);
        }
        override protected string GetParameterName(string parameterName) { 
            return parameterName;
        } 
 
        override protected string GetParameterPlaceholder(int parameterOrdinal) {
            return "?"; 
        }

        override protected void ApplyParameterInfo(DbParameter parameter, DataRow datarow, StatementType statementType, bool whereClause) {
            OdbcParameter p = (OdbcParameter) parameter; 
            object valueType = datarow[SchemaTableColumn.ProviderType];
            p.OdbcType = (OdbcType) valueType; 
 
            object bvalue = datarow[SchemaTableColumn.NumericPrecision];
            if (DBNull.Value != bvalue) { 
                byte bval = (byte)(short)bvalue;
                p.PrecisionInternal = ((0xff != bval) ? bval : (byte)0);
            }
 
            bvalue = datarow[SchemaTableColumn.NumericScale];
            if (DBNull.Value != bvalue) { 
                byte bval = (byte)(short)bvalue; 
                p.ScaleInternal = ((0xff != bval) ? bval : (byte)0);
            } 
        }

        static public void DeriveParameters(OdbcCommand command) {
            // MDAC 65927 
            OdbcConnection.ExecutePermission.Demand();
 
            if (null == command) { 
                throw ADP.ArgumentNull("command");
            } 
            switch (command.CommandType) {
                case System.Data.CommandType.Text:
                    throw ADP.DeriveParametersNotSupported(command);
                case System.Data.CommandType.StoredProcedure: 
                    break;
                case System.Data.CommandType.TableDirect: 
                    // CommandType.TableDirect - do nothing, parameters are not supported 
                    throw ADP.DeriveParametersNotSupported(command);
                default: 
                    throw ADP.InvalidCommandType(command.CommandType);
            }
            if (ADP.IsEmpty(command.CommandText)) {
                throw ADP.CommandTextRequired(ADP.DeriveParameters); 
            }
 
            OdbcConnection connection = command.Connection; 

            if (null == connection) { 
                throw ADP.ConnectionRequired(ADP.DeriveParameters);
            }

            ConnectionState state = connection.State; 

            if (ConnectionState.Open != state) { 
                throw ADP.OpenConnectionRequired(ADP.DeriveParameters, state); 
            }
 
            OdbcParameter[] list = DeriveParametersFromStoredProcedure(connection, command);

            OdbcParameterCollection parameters = command.Parameters;
            parameters.Clear(); 

            int count = list.Length; 
            if (0 < count) { 
                for(int i = 0; i < list.Length; ++i) {
                    parameters.Add(list[i]); 
                }
            }
            }
 

        // DeriveParametersFromStoredProcedure ( 
        //  OdbcConnection connection, 
        //  OdbcCommand command);
        // 
        // Uses SQLProcedureColumns to create an array of OdbcParameters
        //

        static private OdbcParameter[] DeriveParametersFromStoredProcedure(OdbcConnection connection, OdbcCommand command) { 
            List rParams = new List();
 
            // following call ensures that the command has a statement handle allocated 
            CMDWrapper cmdWrapper = command.GetStatementHandle();
            OdbcStatementHandle hstmt = cmdWrapper.StatementHandle; 
            int cColsAffected;

            // maps an enforced 4-part qualified string as follows
            // parts[0] = null  - ignored but removal would be a run-time breaking change from V1.0 
            // parts[1] = CatalogName (optional, may be null)
            // parts[2] = SchemaName (optional, may be null) 
            // parts[3] = ProcedureName 
            //
            string quote = connection.QuoteChar(ADP.DeriveParameters); 
            string[] parts = MultipartIdentifier.ParseMultipartIdentifier(command.CommandText, quote, quote, '.', 4, true, Res.ODBC_ODBCCommandText, false);
            if (null == parts[3]) { // match everett behavior, if the commandtext is nothing but whitespace set the command text to the whitespace
                parts[3] = command.CommandText;
            } 
            // note: native odbc appears to ignore all but the procedure name
            ODBC32.RetCode retcode = hstmt.ProcedureColumns(parts[1], parts[2], parts[3], null); 
 
            // Note: the driver does not return an error if the given stored procedure does not exist
            // therefore we cannot handle that case and just return not parameters. 

            if (ODBC32.RetCode.SUCCESS != retcode) {
                connection.HandleError(hstmt, retcode);
            } 

            using (OdbcDataReader reader = new OdbcDataReader(command, cmdWrapper, CommandBehavior.Default)) { 
                reader.FirstResult(); 
                cColsAffected = reader.FieldCount;
 
                // go through the returned rows and filter out relevant parameter data
                //
                while (reader.Read()) {
                    // devnote: column types are specified in the ODBC Programmer's Reference 
                    // COLUMN_TYPE      Smallint    16bit
                    // COLUMN_SIZE      Integer     32bit 
                    // DECIMAL_DIGITS   Smallint    16bit 
                    // NUM_PREC_RADIX   Smallint    16bit
 
                    OdbcParameter parameter = new OdbcParameter();

                    parameter.ParameterName = reader.GetString(ODBC32.COLUMN_NAME-1);
                    switch ((ODBC32.SQL_PARAM)reader.GetInt16(ODBC32.COLUMN_TYPE-1)){ 
                        case ODBC32.SQL_PARAM.INPUT:
                            parameter.Direction = ParameterDirection.Input; 
                            break; 
                        case ODBC32.SQL_PARAM.OUTPUT:
                            parameter.Direction = ParameterDirection.Output; 
                            break;

                        case ODBC32.SQL_PARAM.INPUT_OUTPUT:
                            parameter.Direction = ParameterDirection.InputOutput; 
                            break;
                        case ODBC32.SQL_PARAM.RETURN_VALUE: 
                            parameter.Direction = ParameterDirection.ReturnValue; 
                            break;
                        default: 
                            Debug.Assert(false, "Unexpected Parametertype while DeriveParamters");
                            break;
                    }
                    parameter.OdbcType = TypeMap.FromSqlType((ODBC32.SQL_TYPE)reader.GetInt16(ODBC32.DATA_TYPE-1))._odbcType; 
                    parameter.Size = (int)reader.GetInt32(ODBC32.COLUMN_SIZE-1);
                    switch(parameter.OdbcType){ 
                        case OdbcType.Decimal: 
                        case OdbcType.Numeric:
                            parameter.ScaleInternal = (Byte)reader.GetInt16(ODBC32.DECIMAL_DIGITS-1); 
                            parameter.PrecisionInternal = (Byte)reader.GetInt16(ODBC32.NUM_PREC_RADIX-1);
                        break;
                    }
                    rParams.Add (parameter); 
                }
            } 
            retcode = hstmt.CloseCursor(); 
            return rParams.ToArray();;
        } 

        public override string QuoteIdentifier(string unquotedIdentifier){
            return QuoteIdentifier(unquotedIdentifier, null /* use DataAdapter.SelectCommand.Connection if available */);
        } 
        public string QuoteIdentifier( string unquotedIdentifier, OdbcConnection connection){
 
            ADP.CheckArgumentNull(unquotedIdentifier, "unquotedIdentifier"); 

            // if the user has specificed a prefix use the user specified  prefix and suffix 
            // otherwise get them from the provider
            string quotePrefix = QuotePrefix;
            string quoteSuffix = QuoteSuffix;
            if (ADP.IsEmpty(quotePrefix) == true) { 
                if (connection == null) {
                    // VSTFDEVDIV 479567: use the adapter's connection if QuoteIdentifier was called from 
                    // DbCommandBuilder instance (which does not have an overload that gets connection object) 
                    connection = base.GetConnection() as OdbcConnection;
                    if (connection == null) { 
                        throw ADP.QuotePrefixNotSet(ADP.QuoteIdentifier);
                    }
                }
                quotePrefix = connection.QuoteChar(ADP.QuoteIdentifier); 
                quoteSuffix = quotePrefix;
            } 
 
            // by the ODBC spec "If the data source does not support quoted identifiers, a blank is returned."
            // So if a blank is returned the string is returned unchanged. Otherwise the returned string is used 
            // to quote the string
            if ((ADP.IsEmpty(quotePrefix) == false) && (quotePrefix != " ")) {
                return ADP.BuildQuotedString(quotePrefix,quoteSuffix,unquotedIdentifier);
            } 
            else {
                return unquotedIdentifier; 
            } 
        }
 


        override protected void SetRowUpdatingHandler(DbDataAdapter adapter) {
            Debug.Assert(adapter is OdbcDataAdapter, "!OdbcDataAdapter"); 
            if (adapter == base.DataAdapter) { // removal case
                ((OdbcDataAdapter)adapter).RowUpdating -= OdbcRowUpdatingHandler; 
            } 
            else { // adding case
                ((OdbcDataAdapter)adapter).RowUpdating += OdbcRowUpdatingHandler; 
            }
        }

        public override string UnquoteIdentifier( string quotedIdentifier){ 
            return UnquoteIdentifier(quotedIdentifier, null /* use DataAdapter.SelectCommand.Connection if available */);
        } 
 
        public string UnquoteIdentifier(string quotedIdentifier, OdbcConnection connection){
 
            ADP.CheckArgumentNull(quotedIdentifier, "quotedIdentifier");


            // if the user has specificed a prefix use the user specified  prefix and suffix 
            // otherwise get them from the provider
            string quotePrefix = QuotePrefix; 
            string quoteSuffix = QuoteSuffix; 
            if (ADP.IsEmpty(quotePrefix) == true) {
                if (connection == null) { 
                    // VSTFDEVDIV 479567: use the adapter's connection if UnquoteIdentifier was called from
                    // DbCommandBuilder instance (which does not have an overload that gets connection object)
                    connection = base.GetConnection() as OdbcConnection;
                    if (connection == null) { 
                        throw ADP.QuotePrefixNotSet(ADP.UnquoteIdentifier);
                    } 
                } 
                quotePrefix = connection.QuoteChar(ADP.UnquoteIdentifier);
                quoteSuffix = quotePrefix; 
            }

            String unquotedIdentifier;
            // by the ODBC spec "If the data source does not support quoted identifiers, a blank is returned." 
            // So if a blank is returned the string is returned unchanged. Otherwise the returned string is used
            // to unquote the string 
            if ((ADP.IsEmpty(quotePrefix) == false) || (quotePrefix != " ")) { 
                // ignoring the return value because it is acceptable for the quotedString to not be quoted in this
                // context. 
                ADP.RemoveStringQuotes(quotePrefix, quoteSuffix, quotedIdentifier, out unquotedIdentifier);
            }
            else {
                unquotedIdentifier = quotedIdentifier; 
            }
            return unquotedIdentifier; 
 
        }
 
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
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OdbcCommandBuilder.cs source code in C# .NET

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