DataServiceQueryProvider.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ Dotnetfx_Vista_SP2 / Dotnetfx_Vista_SP2 / 8.0.50727.4016 / DEVDIV / depot / DevDiv / releases / Orcas / QFE / ndp / fx / src / DataWeb / Client / System / Data / Services / Client / ALinq / DataServiceQueryProvider.cs / 1 / DataServiceQueryProvider.cs

                            //---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//  
//      Query Provider for Linq to URI translatation
//  
// 
// @owner  [....]
//--------------------------------------------------------------------- 

namespace System.Data.Services.Client
{
    using System; 
    using System.Diagnostics;
    using System.Linq; 
    using System.Linq.Expressions; 
    using System.Reflection;
 
    /// 
    /// QueryProvider implementation
    /// 
    internal sealed class DataServiceQueryProvider : IQueryProvider 
    {
        /// DataServiceContext for query provider 
        internal readonly DataServiceContext Context; 

        /// Constructs a query provider based on the context passed in  
        /// The context for the query provider
        internal DataServiceQueryProvider(DataServiceContext context)
        {
            this.Context = context; 
        }
 
        #region IQueryProvider implementation 

        /// Factory method for creating DataServiceOrderedQuery based on expression  
        /// The expression for the new query
        /// new DataServiceQuery
        public IQueryable CreateQuery(Expression expression)
        { 
            Util.CheckArgumentNull(expression, "expression");
            Type et = TypeSystem.GetElementType(expression.Type); 
            Type qt = typeof(DataServiceQuery<>.DataServiceOrderedQuery).MakeGenericType(et); 
            object[] args = new object[] { expression, this };
 
            ConstructorInfo ci = qt.GetConstructor(
                BindingFlags.NonPublic | BindingFlags.Instance,
                null,
                new Type[] { typeof(Expression), typeof(DataServiceQueryProvider) }, 
                null);
 
            return (IQueryable)ci.Invoke(args); 
        }
 
        /// Factory method for creating DataServiceOrderedQuery based on expression 
        /// generic type
        /// The expression for the new query
        /// new DataServiceQuery 
        public IQueryable CreateQuery(Expression expression)
        { 
            Util.CheckArgumentNull(expression, "expression"); 
            return new DataServiceQuery.DataServiceOrderedQuery(expression, this);
        } 

        /// Creates and executes a DataServiceQuery based on the passed in expression
        /// The expression for the new query
        /// the results 
        public object Execute(Expression expression)
        { 
            Util.CheckArgumentNull(expression, "expression"); 

            MethodInfo mi = typeof(DataServiceQueryProvider).GetMethod("ReturnSingleton", BindingFlags.NonPublic | BindingFlags.Instance); 
            return mi.MakeGenericMethod(expression.Type).Invoke(this, new object[] { expression });
        }

        /// Creates and executes a DataServiceQuery based on the passed in expression 
        /// generic type
        /// The expression for the new query 
        /// the results 
        public TResult Execute(Expression expression)
        { 
            Util.CheckArgumentNull(expression, "expression");
            return ReturnSingleton(expression);
        }
 
        #endregion
 
        /// Creates and executes a DataServiceQuery based on the passed in expression which results a single value 
        /// generic type
        /// The expression for the new query 
        /// single valued results
        internal TElement ReturnSingleton(Expression expression)
        {
            IQueryable query = new DataServiceQuery.DataServiceOrderedQuery(expression, this); 

            MethodCallExpression mce = expression as MethodCallExpression; 
            Debug.Assert(mce != null, "mce != null"); 

            SequenceMethod sequenceMethod; 
            if (ReflectionUtil.TryIdentifySequenceMethod(mce.Method, out sequenceMethod))
            {
                switch (sequenceMethod)
                { 
                    case SequenceMethod.Single:
                        return query.AsEnumerable().Single(); 
                    case SequenceMethod.SingleOrDefault: 
                        return query.AsEnumerable().SingleOrDefault();
                    case SequenceMethod.First: 
                        return query.AsEnumerable().First();
                    case SequenceMethod.FirstOrDefault:
                        return query.AsEnumerable().FirstOrDefault();
                    default: 
                        throw Error.MethodNotSupported(mce);
                } 
            } 

            // Should never get here - should be caught by expression compiler. 
            Debug.Assert(false, "Not supported singleton operator not caught by Resource Binder");
            throw Error.MethodNotSupported(mce);
        }
 
        /// Builds the Uri for the expression passed in.
        /// The expression to translate into a Uri 
        /// the resulting Uri 
        internal Uri Translate(Expression e)
        { 
            // short cut analysis if just a resource set
            if (!(e is ResourceSetExpression))
            {
                e = Evaluator.PartialEval(e); 
                e = new ExpressionNormalizer().Visit(e);
                e = ResourceBinder.Bind(e); 
            } 

            string translation = UriWriter.Translate(this.Context, e); 
            return Util.CreateUri(this.Context.BaseUriWithSlash, Util.CreateUri(translation, UriKind.Relative));
        }
    }
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//  
//      Query Provider for Linq to URI translatation
//  
// 
// @owner  [....]
//--------------------------------------------------------------------- 

namespace System.Data.Services.Client
{
    using System; 
    using System.Diagnostics;
    using System.Linq; 
    using System.Linq.Expressions; 
    using System.Reflection;
 
    /// 
    /// QueryProvider implementation
    /// 
    internal sealed class DataServiceQueryProvider : IQueryProvider 
    {
        /// DataServiceContext for query provider 
        internal readonly DataServiceContext Context; 

        /// Constructs a query provider based on the context passed in  
        /// The context for the query provider
        internal DataServiceQueryProvider(DataServiceContext context)
        {
            this.Context = context; 
        }
 
        #region IQueryProvider implementation 

        /// Factory method for creating DataServiceOrderedQuery based on expression  
        /// The expression for the new query
        /// new DataServiceQuery
        public IQueryable CreateQuery(Expression expression)
        { 
            Util.CheckArgumentNull(expression, "expression");
            Type et = TypeSystem.GetElementType(expression.Type); 
            Type qt = typeof(DataServiceQuery<>.DataServiceOrderedQuery).MakeGenericType(et); 
            object[] args = new object[] { expression, this };
 
            ConstructorInfo ci = qt.GetConstructor(
                BindingFlags.NonPublic | BindingFlags.Instance,
                null,
                new Type[] { typeof(Expression), typeof(DataServiceQueryProvider) }, 
                null);
 
            return (IQueryable)ci.Invoke(args); 
        }
 
        /// Factory method for creating DataServiceOrderedQuery based on expression 
        /// generic type
        /// The expression for the new query
        /// new DataServiceQuery 
        public IQueryable CreateQuery(Expression expression)
        { 
            Util.CheckArgumentNull(expression, "expression"); 
            return new DataServiceQuery.DataServiceOrderedQuery(expression, this);
        } 

        /// Creates and executes a DataServiceQuery based on the passed in expression
        /// The expression for the new query
        /// the results 
        public object Execute(Expression expression)
        { 
            Util.CheckArgumentNull(expression, "expression"); 

            MethodInfo mi = typeof(DataServiceQueryProvider).GetMethod("ReturnSingleton", BindingFlags.NonPublic | BindingFlags.Instance); 
            return mi.MakeGenericMethod(expression.Type).Invoke(this, new object[] { expression });
        }

        /// Creates and executes a DataServiceQuery based on the passed in expression 
        /// generic type
        /// The expression for the new query 
        /// the results 
        public TResult Execute(Expression expression)
        { 
            Util.CheckArgumentNull(expression, "expression");
            return ReturnSingleton(expression);
        }
 
        #endregion
 
        /// Creates and executes a DataServiceQuery based on the passed in expression which results a single value 
        /// generic type
        /// The expression for the new query 
        /// single valued results
        internal TElement ReturnSingleton(Expression expression)
        {
            IQueryable query = new DataServiceQuery.DataServiceOrderedQuery(expression, this); 

            MethodCallExpression mce = expression as MethodCallExpression; 
            Debug.Assert(mce != null, "mce != null"); 

            SequenceMethod sequenceMethod; 
            if (ReflectionUtil.TryIdentifySequenceMethod(mce.Method, out sequenceMethod))
            {
                switch (sequenceMethod)
                { 
                    case SequenceMethod.Single:
                        return query.AsEnumerable().Single(); 
                    case SequenceMethod.SingleOrDefault: 
                        return query.AsEnumerable().SingleOrDefault();
                    case SequenceMethod.First: 
                        return query.AsEnumerable().First();
                    case SequenceMethod.FirstOrDefault:
                        return query.AsEnumerable().FirstOrDefault();
                    default: 
                        throw Error.MethodNotSupported(mce);
                } 
            } 

            // Should never get here - should be caught by expression compiler. 
            Debug.Assert(false, "Not supported singleton operator not caught by Resource Binder");
            throw Error.MethodNotSupported(mce);
        }
 
        /// Builds the Uri for the expression passed in.
        /// The expression to translate into a Uri 
        /// the resulting Uri 
        internal Uri Translate(Expression e)
        { 
            // short cut analysis if just a resource set
            if (!(e is ResourceSetExpression))
            {
                e = Evaluator.PartialEval(e); 
                e = new ExpressionNormalizer().Visit(e);
                e = ResourceBinder.Bind(e); 
            } 

            string translation = UriWriter.Translate(this.Context, e); 
            return Util.CreateUri(this.Context.BaseUriWithSlash, Util.CreateUri(translation, UriKind.Relative));
        }
    }
} 

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

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