/mcs/class/dlr/Runtime/Microsoft.Scripting.Core/Actions/ConvertBinder.cs

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  3 * Copyright (c) Microsoft Corporation. 
  4 *
  5 * This source code is subject to terms and conditions of the Microsoft Public License. A 
  6 * copy of the license can be found in the License.html file at the root of this distribution. If 
  7 * you cannot locate the  Microsoft Public License, please send an email to 
  8 * dlr@microsoft.com. By using this source code in any fashion, you are agreeing to be bound 
  9 * by the terms of the Microsoft Public License.
 10 *
 11 * You must not remove this notice, or any other, from this software.
 12 *
 13 *
 14 * ***************************************************************************/
 15
 16using System.Dynamic.Utils;
 17
 18namespace System.Dynamic {
 19    /// <summary>
 20    /// Represents the convert dynamic operation at the call site, providing the binding semantic and the details about the operation.
 21    /// </summary>
 22    public abstract class ConvertBinder : DynamicMetaObjectBinder {
 23        private readonly Type _type;
 24        private readonly bool _explicit;
 25
 26        /// <summary>
 27        /// Initializes a new intsance of the <see cref="ConvertBinder" />.
 28        /// </summary>
 29        /// <param name="type">The type to convert to.</param>
 30        /// <param name="explicit">true if the conversion should consider explicit conversions; otherwise, false.</param>
 31        protected ConvertBinder(Type type, bool @explicit) {
 32            ContractUtils.RequiresNotNull(type, "type");
 33
 34            _type = type;
 35            _explicit = @explicit;
 36        }
 37
 38        /// <summary>
 39        /// The type to convert to.
 40        /// </summary>
 41        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1721:PropertyNamesShouldNotMatchGetMethods")]
 42        public Type Type {
 43            get {
 44                return _type;
 45            }
 46        }
 47
 48        /// <summary>
 49        /// Gets the value indicating if the conversion should consider explicit conversions.
 50        /// </summary>
 51        public bool Explicit {
 52            get {
 53                return _explicit;
 54            }
 55        }
 56
 57        /// <summary>
 58        /// Performs the binding of the dynamic convert operation if the target dynamic object cannot bind.
 59        /// </summary>
 60        /// <param name="target">The target of the dynamic convert operation.</param>
 61        /// <returns>The <see cref="DynamicMetaObject"/> representing the result of the binding.</returns>
 62        public DynamicMetaObject FallbackConvert(DynamicMetaObject target) {
 63            return FallbackConvert(target, null);
 64        }
 65
 66        /// <summary>
 67        /// When overridden in the derived class, performs the binding of the dynamic convert operation if the target dynamic object cannot bind.
 68        /// </summary>
 69        /// <param name="target">The target of the dynamic convert operation.</param>
 70        /// <param name="errorSuggestion">The binding result to use if binding fails, or null.</param>
 71        /// <returns>The <see cref="DynamicMetaObject"/> representing the result of the binding.</returns>
 72        public abstract DynamicMetaObject FallbackConvert(DynamicMetaObject target, DynamicMetaObject errorSuggestion);
 73
 74        /// <summary>
 75        /// Performs the binding of the dynamic convert operation.
 76        /// </summary>
 77        /// <param name="target">The target of the dynamic convert operation.</param>
 78        /// <param name="args">An array of arguments of the dynamic convert operation.</param>
 79        /// <returns>The <see cref="DynamicMetaObject"/> representing the result of the binding.</returns>
 80        public sealed override DynamicMetaObject Bind(DynamicMetaObject target, DynamicMetaObject[] args) {
 81            ContractUtils.RequiresNotNull(target, "target");
 82            ContractUtils.Requires(args == null || args.Length == 0, "args");
 83
 84            return target.BindConvert(this);
 85        }
 86
 87        // this is a standard DynamicMetaObjectBinder
 88        internal override sealed bool IsStandardBinder {
 89            get {
 90                return true;
 91            }
 92        }
 93
 94        /// <summary>
 95        /// The result type of the operation.
 96        /// </summary>
 97        public override sealed Type ReturnType {
 98            get { return _type; }
 99        }
100    }
101}