FunctionDetailsReader.cs source code in C# .NET

                        Code:
                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / DataEntityDesign / Design / System / Data / Entity / Design / SSDLGenerator / FunctionDetailsReader.cs / 1305376 / FunctionDetailsReader.cs
                        
                        
                            //---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// 
// @owner       [....]
// @backupOwner [....] 
//--------------------------------------------------------------------- 
using System;
using System.Collections.Generic; 
using System.Text;
using System.Data.Common;
using System.Data.EntityClient;
using System.Diagnostics; 
using System.Data.Metadata.Edm;
 
namespace System.Data.Entity.Design.SsdlGenerator 
{
    // the purpose of this class is to give us strongly typed access to 
    // the results of the reader
    //
    // NOTE this class will dispose of the command when the reader is disposed
    // 
    internal class FunctionDetailsReader : IDisposable
    { 
        private DbDataReader _reader; 
        private EntityCommand _command;
        private EntityConnection _connection; 
        private object[] _currentRow;


        internal FunctionDetailsReader(FunctionDetailsReader.Memento memento) 
        {
            _currentRow = memento.Values; 
        } 

        internal FunctionDetailsReader(EntityConnection connection, IEnumerable filters) 
        {
            Debug.Assert(connection != null, "the parameter connection is null");
            Debug.Assert(connection.State == ConnectionState.Open, "the connection is not Open");
 
            _connection = connection;
 
            _command = EntityStoreSchemaGeneratorDatabaseSchemaLoader.CreateFilteredCommand( 
                        _connection,
                        FunctionDetailSql, 
                        FunctionOrderByClause,
                        EntityStoreSchemaFilterObjectTypes.Function,
                        new List(filters),
                        new string [] {FunctionDetailAlias}); 
            _reader = _command.ExecuteReader(CommandBehavior.SequentialAccess);
        } 
 
        internal bool Read()
        { 
            Debug.Assert(_reader != null, "don't Read() when it is created from a memento");
            bool haveRow = _reader.Read();
            if (haveRow)
            { 
                if(_currentRow == null)
                { 
                    _currentRow = new object[COLUMN_COUNT]; 
                }
                _reader.GetValues(_currentRow); 
            }
            else
            {
                _currentRow = null; 
            }
            return haveRow; 
        } 

        public void Dispose() 
        {
            // Technically, calling GC.SuppressFinalize is not required because the class does not
            // have a finalizer, but it does no harm, protects against the case where a finalizer is added
            // in the future, and prevents an FxCop warning. 
            GC.SuppressFinalize(this);
            Debug.Assert(_reader != null, "don't Dispose() when it is created from a memento"); 
            _reader.Dispose(); 
            _command.Dispose();
        } 

        internal void Attach(Memento memento)
        {
            Debug.Assert(memento != null, "the parameter memento is null"); 
            Debug.Assert(memento.Values != null, "the values in the memento are null");
            Debug.Assert(_reader == null, "don't attach to a real reader"); 
            _currentRow = memento.Values; 
        }
 
        const int PROC_SCHEMA_INDEX = 0;
        const int PROC_NAME_INDEX = 1;
        const int PROC_RET_TYPE_INDEX = 2;
        const int PROC_ISAGGREGATE_INDEX = 3; 
        const int PROC_ISCOMPOSABLE_INDEX = 4;
        const int PROC_ISBUILTIN_INDEX = 5; 
        const int PROC_ISNILADIC_INDEX = 6; 
        const int PARAM_NAME_INDEX = 7;
        const int PARAM_TYPE_INDEX = 8; 
        const int PARAM_DIRECTION_INDEX = 9;
        const int COLUMN_COUNT = 10;

        internal bool IsSchemaNull 
        {
            get { return Convert.IsDBNull(_currentRow[PROC_SCHEMA_INDEX]); } 
        } 

        internal string Schema 
        {
            get { return (string)_currentRow[PROC_SCHEMA_INDEX]; }
        }
 
        internal string ProcedureName
        { 
            get { return (string)_currentRow[PROC_NAME_INDEX]; } 
        }
 
        internal string ReturnType
        {
            get { return (string)_currentRow[PROC_RET_TYPE_INDEX]; }
        } 

        internal bool IsReturnTypeNull 
        { 
            get {return Convert.IsDBNull(_currentRow[PROC_RET_TYPE_INDEX]);}
        } 

        internal bool IsIsAggregate
        {
            get 
            {
                if(Convert.IsDBNull(_currentRow[PROC_ISAGGREGATE_INDEX])) 
                    return false; 

                return (bool)_currentRow[PROC_ISAGGREGATE_INDEX]; 
            }
        }

        internal bool IsBuiltIn 
        {
            get 
            { 
                if (Convert.IsDBNull(_currentRow[PROC_ISBUILTIN_INDEX]))
                    return false; 

                return (bool)_currentRow[PROC_ISBUILTIN_INDEX];
            }
        } 

        internal bool IsComposable 
        { 
            get
            { 
                if(Convert.IsDBNull(_currentRow[PROC_ISCOMPOSABLE_INDEX]))
                    return false;

                return (bool)_currentRow[PROC_ISCOMPOSABLE_INDEX]; 
            }
        } 
 

        internal bool IsNiladic 
        {
            get
            {
                if(Convert.IsDBNull(_currentRow[PROC_ISNILADIC_INDEX])) 
                    return false;
 
                return (bool)_currentRow[PROC_ISNILADIC_INDEX]; 
            }
        } 

        internal string ParameterName
        {
            get { return (string)_currentRow[PARAM_NAME_INDEX]; } 
        }
 
        internal bool IsParameterNameNull 
        {
            get { return Convert.IsDBNull(_currentRow[PARAM_NAME_INDEX]); } 
        }

        internal string ParameterType
        { 
            get { return (string)_currentRow[PARAM_TYPE_INDEX]; }
        } 
 
        internal bool IsParameterTypeNull
        { 
            get {return Convert.IsDBNull(_currentRow[PARAM_TYPE_INDEX]);}
        }

        internal string ProcParameterMode 
        {
            get { return (string)_currentRow[PARAM_DIRECTION_INDEX]; } 
        } 

        internal bool IsParameterModeNull 
        {
            get { return Convert.IsDBNull(_currentRow[PARAM_DIRECTION_INDEX]); }
        }
 
        internal bool TryGetParameterMode(out ParameterMode mode)
        { 
            if (IsParameterModeNull) 
            {
                mode = (ParameterMode)(-1); 
                return false;
            }

            switch(ProcParameterMode) 
            {
                case "IN": 
                    mode = ParameterMode.In; 
                    return true;
                case "OUT": 
                    mode = ParameterMode.Out;
                    return true;
                case "INOUT":
                    mode = ParameterMode.InOut; 
                    return true;
                default: 
                    mode = (ParameterMode)(-1); 
                    return false;
            } 
        }
        internal EntityStoreSchemaGenerator.DbObjectKey CreateDbObjectKey()
        {
            Debug.Assert(_currentRow != null, "don't call this method when you not reading"); 
            return new EntityStoreSchemaGenerator.DbObjectKey(null, _currentRow[PROC_SCHEMA_INDEX], _currentRow[PROC_NAME_INDEX], EntityStoreSchemaGenerator.DbObjectType.Function);
        } 
 
        internal Memento CreateMemento()
        { 
            Debug.Assert(_currentRow != null, "don't call this method when you not reading");
            return new Memento((object[])_currentRow.Clone());
        }
 
        private static readonly string FunctionDetailAlias = "sp";
        private static readonly string FunctionDetailSql = @" 
            SELECT 
                  sp.SchemaName
                , sp.Name 
                , sp.ReturnTypeName
                , sp.IsAggregate
                , sp.IsComposable
                , sp.IsBuiltIn 
                , sp.IsNiladic
                , sp.ParameterName 
                , sp.ParameterType 
                , sp.Mode
            FROM ( 
            (SELECT
                  r.CatalogName as CatalogName
              ,   r.SchemaName as SchemaName
              ,   r.Name as Name 
              ,   r.ReturnType.TypeName as ReturnTypeName
              ,   r.IsAggregate as IsAggregate 
              ,   true as IsComposable 
              ,   r.IsBuiltIn as IsBuiltIn
              ,   r.IsNiladic as IsNiladic 
              ,   p.Name as ParameterName
              ,   p.ParameterType.TypeName as ParameterType
              ,   p.Mode as Mode
              ,   p.Ordinal as Ordinal 
            FROM
                OfType(SchemaInformation.Functions, Store.ScalarFunction) as r 
                 OUTER APPLY 
                r.Parameters as p)
            UNION ALL 
            (SELECT
                  r.CatalogName as CatalogName
              ,   r.SchemaName as SchemaName
              ,   r.Name as Name 
              ,   CAST(NULL as string) as ReturnTypeName
              ,   false as IsAggregate 
              ,   false as IsComposable 
              ,   false as IsBuiltIn
              ,   false as IsNiladic 
              ,   p.Name as ParameterName
              ,   p.ParameterType.TypeName as ParameterType
              ,   p.Mode as Mode
              ,   p.Ordinal as Ordinal 
            FROM
                SchemaInformation.Procedures as r 
                 OUTER APPLY 
                r.Parameters as p)) as sp
            "; 


        private static readonly string FunctionOrderByClause = @"
            ORDER BY 
                sp.SchemaName
            ,   sp.Name 
            ,   sp.Ordinal 
            ";
 
        internal class Memento
        {
            private object[] _values;
            internal Memento(object[] values) 
            {
                _values = values; 
            } 

            internal object[] Values 
            {
                get { return _values; }
            }
 
            internal FunctionDetailsReader CreateReader()
            { 
                return new FunctionDetailsReader(this); 
            }
        } 

    }
}

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

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