/IronPython_Main/Runtime/Microsoft.Scripting.Core/Actions/GetMemberBinder.cs

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 *

 * Copyright (c) Microsoft Corporation. 

 *

 * This source code is subject to terms and conditions of the Apache License, Version 2.0. A 

 * copy of the license can be found in the License.html file at the root of this distribution. If 

 * you cannot locate the  Apache License, Version 2.0, please send an email to 

 * dlr@microsoft.com. By using this source code in any fashion, you are agreeing to be bound 

 * by the terms of the Apache License, Version 2.0.

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 * You must not remove this notice, or any other, from this software.

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using System.Dynamic.Utils;



namespace System.Dynamic {

    /// <summary>

    /// Represents the dynamic get member operation at the call site, providing the binding semantic and the details about the operation.

    /// </summary>

    public abstract class GetMemberBinder : DynamicMetaObjectBinder {

        private readonly string _name;

        private readonly bool _ignoreCase;



        /// <summary>

        /// Initializes a new instance of the <see cref="GetMemberBinder" />.

        /// </summary>

        /// <param name="name">The name of the member to get.</param>

        /// <param name="ignoreCase">true if the name should be matched ignoring case; false otherwise.</param>

        protected GetMemberBinder(string name, bool ignoreCase) {

            ContractUtils.RequiresNotNull(name, "name");



            _name = name;

            _ignoreCase = ignoreCase;

        }



        /// <summary>

        /// The result type of the operation.

        /// </summary>

        public override sealed Type ReturnType {

            get { return typeof(object); }

        }



        /// <summary>

        /// Gets the name of the member to get.

        /// </summary>

        public string Name {

            get {

                return _name;

            }

        }



        /// <summary>

        /// Gets the value indicating if the string comparison should ignore the case of the member name.

        /// </summary>

        public bool IgnoreCase {

            get {

                return _ignoreCase;

            }

        }



        /// <summary>

        /// Performs the binding of the dynamic get member operation if the target dynamic object cannot bind.

        /// </summary>

        /// <param name="target">The target of the dynamic get member operation.</param>

        /// <returns>The <see cref="DynamicMetaObject"/> representing the result of the binding.</returns>

        public DynamicMetaObject FallbackGetMember(DynamicMetaObject target) {

            return FallbackGetMember(target, null);

        }



        /// <summary>

        /// When overridden in the derived class, performs the binding of the dynamic get member operation if the target dynamic object cannot bind.

        /// </summary>

        /// <param name="target">The target of the dynamic get member operation.</param>

        /// <param name="errorSuggestion">The binding result to use if binding fails, or null.</param>

        /// <returns>The <see cref="DynamicMetaObject"/> representing the result of the binding.</returns>

        public abstract DynamicMetaObject FallbackGetMember(DynamicMetaObject target, DynamicMetaObject errorSuggestion);



        /// <summary>

        /// Performs the binding of the dynamic get member operation.

        /// </summary>

        /// <param name="target">The target of the dynamic get member operation.</param>

        /// <param name="args">An array of arguments of the dynamic get member operation.</param>

        /// <returns>The <see cref="DynamicMetaObject"/> representing the result of the binding.</returns>

        public sealed override DynamicMetaObject Bind(DynamicMetaObject target, params DynamicMetaObject[] args) {

            ContractUtils.RequiresNotNull(target, "target");

            ContractUtils.Requires(args == null || args.Length == 0, "args");



            return target.BindGetMember(this);

        }



        // this is a standard DynamicMetaObjectBinder

        internal override sealed bool IsStandardBinder {

            get {

                return true;

            }

        }

    }

}