ObjectSet.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / DataEntity / System / Data / Objects / ObjectSet.cs / 1305376 / ObjectSet.cs

                            //---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// 
// @owner       [....]
// @backupOwner [....] 
// 
// ObjectSet is a wrapper around ObjectQuery and CUD
// methods on the ObjectContext. It provides a single source that can 
// be used to build queries over an EntitySet as well as perform CUD operations.
//
// devnote: This methods on this class are expected to behave exactly
//          like the ObjectContext methods to which they delegate. Therefore, 
//          they should do very little, if any, extra work aside from a
//          single call to delegate to the appropriate ObjectContext method. 
//          The only exceptions to this are cases where we need to do 
//          additional validation that is specific to ObjectSet, such as
//          verifying that an object is in the appropriate EntitySet during 
//          DeleteObject and Detach operations. We also should not override
//          or otherwise change ObjectQuery behavior. Users should be able to
//          use an ObjectSet in exactly the same ways they can use an
//          ObjectQuery, except for the fact that the CommandText is 
//          determined by the EntitySet name, and cannot be controlled by the user.
//--------------------------------------------------------------------- 
 
using System.Collections;
using System.Collections.Generic; 
using System.Data.Metadata.Edm;
using System.Globalization;
using System.Diagnostics;
 
namespace System.Data.Objects
{ 
    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1710:IdentifiersShouldHaveCorrectSuffix")] 
    public class ObjectSet : ObjectQuery, IObjectSet
        where TEntity : class 
    {
        private readonly EntitySet _entitySet;

        #region Internal Constructors 
        /// 
        /// Creates a new ObjectSet that has a base ObjectQuery with the CommandText that represents 
        /// all of the entities in the specified EntitySet. 
        /// Sets the query's command text to the fully-qualified, quoted, EntitySet name, i.e. [EntityContainerName].[EntitySetName]
        /// Explicitly set MergeOption to AppendOnly in order to mirror CreateQuery behavior 
        /// 
        /// Metadata EntitySet on which to base the ObjectSet.
        /// ObjectContext to be used for the query and data modification operations.
        internal ObjectSet(EntitySet entitySet, ObjectContext context) 
            : base(
                String.Format( 
                    CultureInfo.InvariantCulture, 
                    "{0}.{1}",
                    EntityUtil.QuoteIdentifier(entitySet.EntityContainer.Name), 
                    EntityUtil.QuoteIdentifier(entitySet.Name)),
                context,
                MergeOption.AppendOnly)
        { 
            Debug.Assert(entitySet != null, "ObjectSet constructor requires a non-null EntitySet");
            Debug.Assert(context != null, "ObjectSet constructor requires a non-null ObjectContext"); 
            _entitySet = entitySet; 
        }
        #endregion 

        #region Public Properties
        /// 
        /// Provides metadata for the EntitySet that is represented by the ObjectSet 
        /// 
        public EntitySet EntitySet 
        { 
            get
            { 
                return _entitySet;
            }
        }
        #endregion 

        #region Public Methods 
        ///  
        /// Adds an object to the ObjectContext using the EntitySet referenced by this ObjectSet.
        /// See ObjectContext.AddObject for more details. 
        /// 
        /// Entity to be added
        public void AddObject(TEntity entity)
        { 
            // this method is expected to behave exactly like ObjectContext.AddObject -- see devnote at the top of this class
            this.Context.AddObject(FullyQualifiedEntitySetName, entity); 
        } 

        ///  
        /// Attaches an object to the ObjectContext using the EntitySet referenced by this ObjectSet.
        /// See ObjectContext.AttachTo for more details.
        /// 
        /// Entity to be attached 
        public void Attach(TEntity entity)
        { 
            // this method is expected to behave exactly like ObjectContext.AttachTo -- see devnote at the top of this class 
            this.Context.AttachTo(FullyQualifiedEntitySetName, entity);
        } 

        /// 
        /// Deletes an object from the ObjectContext. Validates that the object is in the referenced EntitySet in the context.
        /// See ObjectContext.DeleteObject for more details. 
        /// 
        /// Entity to be deleted. 
        /// Throws if the specified object is not in the EntitySet. 
        public void DeleteObject(TEntity entity)
        { 
            // this method is expected to behave exactly like ObjectContext.DeleteObject -- see devnote at the top of this class
            // Note that in this case we use an internal DeleteObject overload so we can have the context validate
            // the EntitySet after it verifies that the specified object is in the context at all.
            this.Context.DeleteObject(entity, EntitySet); 
        }
 
        ///  
        /// Detaches an object from the ObjectContext. Validates that the object is in the referenced EntitySet in the context.
        /// See ObjectContext.Detach for more details. 
        /// 
        /// Entity to be detached.
        /// Throws if the specified object is not in the EntitySet.
        public void Detach(TEntity entity) 
        {
            // this method is expected to behave exactly like ObjectContext.Detach -- see devnote at the top of this class 
            // Note that in this case we use an internal Detach overload so we can have the context validate 
            // the EntitySet after it verifies that the specified object is in the context at all.
            this.Context.Detach(entity, EntitySet); 
        }

        /// 
        /// Applies changes from one object to another with the same key in the ObjectContext. 
        /// See ObjectContext.ApplyCurrentValues for more details.
        ///  
        /// Entity that contains changes to be applied. 
        public TEntity ApplyCurrentValues(TEntity currentEntity)
        { 
            // this method is expected to behave exactly like ObjectContext.ApplyCurrentValues -- see devnote at the top of this class
            return this.Context.ApplyCurrentValues(FullyQualifiedEntitySetName, currentEntity);
        }
 
        /// 
        /// Apply modified properties to the original object with the same key in the ObjectContext. 
        /// See ObjectContext.ApplyOriginalValues for more details. 
        /// 
        /// Entity that contains values to be applied. 
        public TEntity ApplyOriginalValues(TEntity originalEntity)
        {
            // this method is expected to behave exactly like ObjectContext.ApplyOriginalValues -- see devnote at the top of this class
            return this.Context.ApplyOriginalValues(FullyQualifiedEntitySetName, originalEntity); 
        }
 
        ///  
        /// Create an instance of the type .
        ///  
        /// 
        /// An instance of an object of type .
        /// The object will either be an instance of the exact type ,
        /// or possibly an instance of the proxy type that corresponds to . 
        /// 
        public TEntity CreateObject() 
        { 
            return this.Context.CreateObject();
        } 

        /// 
        /// Create an instance of the type .
        ///  
        /// 
        /// An instance of an object of type . 
        /// The object will either be an instance of the exact type , 
        /// or possibly an instance of the proxy type that corresponds to .
        ///  
        public T CreateObject() where T : class, TEntity
        {
            return this.Context.CreateObject();
        } 

        #endregion 
 
        #region Private Properties
        // Used 
        private string FullyQualifiedEntitySetName
        {
            get
            { 
                // Fully-qualified name is used to ensure the ObjectContext can always resolve the EntitySet name
                // The identifiers used here should not be escaped with brackets ("[]") because the ObjectContext does not allow escaping for the EntitySet name 
                return string.Format(CultureInfo.InvariantCulture, "{0}.{1}", _entitySet.EntityContainer.Name, _entitySet.Name); 
            }
        } 
        #endregion
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// 
// @owner       [....]
// @backupOwner [....] 
// 
// ObjectSet is a wrapper around ObjectQuery and CUD
// methods on the ObjectContext. It provides a single source that can 
// be used to build queries over an EntitySet as well as perform CUD operations.
//
// devnote: This methods on this class are expected to behave exactly
//          like the ObjectContext methods to which they delegate. Therefore, 
//          they should do very little, if any, extra work aside from a
//          single call to delegate to the appropriate ObjectContext method. 
//          The only exceptions to this are cases where we need to do 
//          additional validation that is specific to ObjectSet, such as
//          verifying that an object is in the appropriate EntitySet during 
//          DeleteObject and Detach operations. We also should not override
//          or otherwise change ObjectQuery behavior. Users should be able to
//          use an ObjectSet in exactly the same ways they can use an
//          ObjectQuery, except for the fact that the CommandText is 
//          determined by the EntitySet name, and cannot be controlled by the user.
//--------------------------------------------------------------------- 
 
using System.Collections;
using System.Collections.Generic; 
using System.Data.Metadata.Edm;
using System.Globalization;
using System.Diagnostics;
 
namespace System.Data.Objects
{ 
    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1710:IdentifiersShouldHaveCorrectSuffix")] 
    public class ObjectSet : ObjectQuery, IObjectSet
        where TEntity : class 
    {
        private readonly EntitySet _entitySet;

        #region Internal Constructors 
        /// 
        /// Creates a new ObjectSet that has a base ObjectQuery with the CommandText that represents 
        /// all of the entities in the specified EntitySet. 
        /// Sets the query's command text to the fully-qualified, quoted, EntitySet name, i.e. [EntityContainerName].[EntitySetName]
        /// Explicitly set MergeOption to AppendOnly in order to mirror CreateQuery behavior 
        /// 
        /// Metadata EntitySet on which to base the ObjectSet.
        /// ObjectContext to be used for the query and data modification operations.
        internal ObjectSet(EntitySet entitySet, ObjectContext context) 
            : base(
                String.Format( 
                    CultureInfo.InvariantCulture, 
                    "{0}.{1}",
                    EntityUtil.QuoteIdentifier(entitySet.EntityContainer.Name), 
                    EntityUtil.QuoteIdentifier(entitySet.Name)),
                context,
                MergeOption.AppendOnly)
        { 
            Debug.Assert(entitySet != null, "ObjectSet constructor requires a non-null EntitySet");
            Debug.Assert(context != null, "ObjectSet constructor requires a non-null ObjectContext"); 
            _entitySet = entitySet; 
        }
        #endregion 

        #region Public Properties
        /// 
        /// Provides metadata for the EntitySet that is represented by the ObjectSet 
        /// 
        public EntitySet EntitySet 
        { 
            get
            { 
                return _entitySet;
            }
        }
        #endregion 

        #region Public Methods 
        ///  
        /// Adds an object to the ObjectContext using the EntitySet referenced by this ObjectSet.
        /// See ObjectContext.AddObject for more details. 
        /// 
        /// Entity to be added
        public void AddObject(TEntity entity)
        { 
            // this method is expected to behave exactly like ObjectContext.AddObject -- see devnote at the top of this class
            this.Context.AddObject(FullyQualifiedEntitySetName, entity); 
        } 

        ///  
        /// Attaches an object to the ObjectContext using the EntitySet referenced by this ObjectSet.
        /// See ObjectContext.AttachTo for more details.
        /// 
        /// Entity to be attached 
        public void Attach(TEntity entity)
        { 
            // this method is expected to behave exactly like ObjectContext.AttachTo -- see devnote at the top of this class 
            this.Context.AttachTo(FullyQualifiedEntitySetName, entity);
        } 

        /// 
        /// Deletes an object from the ObjectContext. Validates that the object is in the referenced EntitySet in the context.
        /// See ObjectContext.DeleteObject for more details. 
        /// 
        /// Entity to be deleted. 
        /// Throws if the specified object is not in the EntitySet. 
        public void DeleteObject(TEntity entity)
        { 
            // this method is expected to behave exactly like ObjectContext.DeleteObject -- see devnote at the top of this class
            // Note that in this case we use an internal DeleteObject overload so we can have the context validate
            // the EntitySet after it verifies that the specified object is in the context at all.
            this.Context.DeleteObject(entity, EntitySet); 
        }
 
        ///  
        /// Detaches an object from the ObjectContext. Validates that the object is in the referenced EntitySet in the context.
        /// See ObjectContext.Detach for more details. 
        /// 
        /// Entity to be detached.
        /// Throws if the specified object is not in the EntitySet.
        public void Detach(TEntity entity) 
        {
            // this method is expected to behave exactly like ObjectContext.Detach -- see devnote at the top of this class 
            // Note that in this case we use an internal Detach overload so we can have the context validate 
            // the EntitySet after it verifies that the specified object is in the context at all.
            this.Context.Detach(entity, EntitySet); 
        }

        /// 
        /// Applies changes from one object to another with the same key in the ObjectContext. 
        /// See ObjectContext.ApplyCurrentValues for more details.
        ///  
        /// Entity that contains changes to be applied. 
        public TEntity ApplyCurrentValues(TEntity currentEntity)
        { 
            // this method is expected to behave exactly like ObjectContext.ApplyCurrentValues -- see devnote at the top of this class
            return this.Context.ApplyCurrentValues(FullyQualifiedEntitySetName, currentEntity);
        }
 
        /// 
        /// Apply modified properties to the original object with the same key in the ObjectContext. 
        /// See ObjectContext.ApplyOriginalValues for more details. 
        /// 
        /// Entity that contains values to be applied. 
        public TEntity ApplyOriginalValues(TEntity originalEntity)
        {
            // this method is expected to behave exactly like ObjectContext.ApplyOriginalValues -- see devnote at the top of this class
            return this.Context.ApplyOriginalValues(FullyQualifiedEntitySetName, originalEntity); 
        }
 
        ///  
        /// Create an instance of the type .
        ///  
        /// 
        /// An instance of an object of type .
        /// The object will either be an instance of the exact type ,
        /// or possibly an instance of the proxy type that corresponds to . 
        /// 
        public TEntity CreateObject() 
        { 
            return this.Context.CreateObject();
        } 

        /// 
        /// Create an instance of the type .
        ///  
        /// 
        /// An instance of an object of type . 
        /// The object will either be an instance of the exact type , 
        /// or possibly an instance of the proxy type that corresponds to .
        ///  
        public T CreateObject() where T : class, TEntity
        {
            return this.Context.CreateObject();
        } 

        #endregion 
 
        #region Private Properties
        // Used 
        private string FullyQualifiedEntitySetName
        {
            get
            { 
                // Fully-qualified name is used to ensure the ObjectContext can always resolve the EntitySet name
                // The identifiers used here should not be escaped with brackets ("[]") because the ObjectContext does not allow escaping for the EntitySet name 
                return string.Format(CultureInfo.InvariantCulture, "{0}.{1}", _entitySet.EntityContainer.Name, _entitySet.Name); 
            }
        } 
        #endregion
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
                        

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