ValueTypeIndexerReference.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / cdf / src / NetFx40 / System.Activities / System / Activities / Expressions / ValueTypeIndexerReference.cs / 1305376 / ValueTypeIndexerReference.cs

                            //------------------------------------------------------------------------------ 
// Copyright (c) Microsoft Corporation.  All rights reserved.
//-----------------------------------------------------------------------------

namespace System.Activities.Expressions 
{
    using System.Collections.ObjectModel; 
    using System.ComponentModel; 
    using System.Reflection;
    using System.Runtime; 
    using System.Runtime.Collections;
    using System.Runtime.Serialization;
    using System.Windows.Markup;
 
    [ContentProperty("Indices")]
    public sealed class ValueTypeIndexerReference : CodeActivity> 
    { 
        Collection indices;
        MethodInfo getMethod; 
        MethodInfo setMethod;

        [RequiredArgument]
        [DefaultValue(null)] 
        public InOutArgument OperandLocation
        { 
            get; 
            set;
        } 

        [RequiredArgument]
        [DefaultValue(null)]
        public Collection Indices 
        {
            get 
            { 
                if (this.indices == null)
                { 
                    this.indices = new ValidatingCollection
                    {
                        // disallow null values
                        OnAddValidationCallback = item => 
                        {
                            if (item == null) 
                            { 
                                throw FxTrace.Exception.ArgumentNull("item");
                            } 
                        },
                    };
                }
                return this.indices; 
            }
        } 
 
        protected override void CacheMetadata(CodeActivityMetadata metadata)
        { 
            if (!typeof(TOperand).IsValueType)
            {
                metadata.AddValidationError(SR.TypeMustbeValueType(typeof(TOperand).Name));
            } 
            if (this.Indices.Count == 0)
            { 
                metadata.AddValidationError(SR.IndicesAreNeeded(this.GetType().Name, this.DisplayName)); 
            }
            else 
            {
                IndexerHelper.CacheMethod(this.Indices, ref this.getMethod, ref this.setMethod);
                if (this.setMethod == null)
                { 
                    metadata.AddValidationError(SR.SpecialMethodNotFound("set_Item", typeof(TOperand).Name));
                } 
            } 

            RuntimeArgument operandArgument = new RuntimeArgument("OperandLocation", typeof(TOperand), ArgumentDirection.InOut, true); 
            metadata.Bind(this.OperandLocation, operandArgument);
            metadata.AddArgument(operandArgument);

            IndexerHelper.OnGetArguments(this.Indices, this.Result, metadata); 
        }
 
        protected override Location Execute(CodeActivityContext context) 
        {
            object[] indicesValue = new object[this.Indices.Count]; 
            for (int i = 0; i < this.Indices.Count; i++)
            {
                indicesValue[i] = this.Indices[i].Get(context);
            } 
            Location operandLocationValue = this.OperandLocation.GetLocation(context);
            Fx.Assert(operandLocationValue != null, "OperandLocation must not be null"); 
            return new IndexerLocation(operandLocationValue, indicesValue, getMethod, setMethod); 
        }
 
        [DataContract]
        class IndexerLocation : Location
        {
            [DataMember(EmitDefaultValue = false)] 
            Location operandLocation;
 
            [DataMember(EmitDefaultValue = false)] 
            object[] indices;
 
            [DataMember(EmitDefaultValue = false)]
            object[] parameters;

            [DataMember(EmitDefaultValue = false)] 
            MethodInfo getMethod;
 
            [DataMember(EmitDefaultValue = false)] 
            MethodInfo setMethod;
 
            public IndexerLocation(Location operandLocation, object[] indices, MethodInfo getMethod, MethodInfo setMethod)
                : base()
            {
                this.operandLocation = operandLocation; 
                this.indices = indices;
                this.getMethod = getMethod; 
                this.setMethod = setMethod; 
            }
 
            public override TItem Value
            {
                get
                { 
                    Fx.Assert(this.operandLocation != null, "operandLocation must not be null");
                    Fx.Assert(this.indices != null, "indices must not be null"); 
                    if (this.getMethod == null) 
                    {
                        throw FxTrace.Exception.AsError(new InvalidOperationException(SR.SpecialMethodNotFound("get_Item", typeof(TOperand).Name))); 
                    }
                    return (TItem)this.getMethod.Invoke(this.operandLocation.Value, indices);
                }
                set 
                {
                    Fx.Assert(this.setMethod != null, "setMethod must not be null"); 
                    Fx.Assert(this.operandLocation != null, "operandLocation must not be null"); 
                    Fx.Assert(this.indices != null, "indices must not be null");
 
                    if (this.parameters == null)
                    {
                        this.parameters = new object[this.indices.Length + 1];
                        for (int i = 0; i < this.indices.Length; i++) 
                        {
                            parameters[i] = this.indices[i]; 
                        } 
                        parameters[parameters.Length - 1] = value;
                    } 
                    object copy = this.operandLocation.Value;
                    this.setMethod.Invoke(copy, parameters);
                    this.operandLocation.Value = (TOperand) copy;
                } 
            }
        } 
    } 
}

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

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