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Diffstat (limited to 'csharp/src/Google.Protobuf/Compatibility/TypeExtensions.cs')
-rw-r--r-- | csharp/src/Google.Protobuf/Compatibility/TypeExtensions.cs | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/csharp/src/Google.Protobuf/Compatibility/TypeExtensions.cs b/csharp/src/Google.Protobuf/Compatibility/TypeExtensions.cs new file mode 100644 index 00000000..762a29eb --- /dev/null +++ b/csharp/src/Google.Protobuf/Compatibility/TypeExtensions.cs @@ -0,0 +1,113 @@ +#region Copyright notice and license +// Protocol Buffers - Google's data interchange format +// Copyright 2015 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +#endregion + +using System; +using System.Reflection; + +namespace Google.Protobuf.Compatibility +{ + /// <summary> + /// Provides extension methods on Type that just proxy to TypeInfo. + /// These are used to support the new type system from .NET 4.5, without + /// having calls to GetTypeInfo all over the place. While the methods here are meant to be + /// broadly compatible with the desktop framework, there are some subtle differences in behaviour - but + /// they're not expected to affect our use cases. While the class is internal, that should be fine: we can + /// evaluate each new use appropriately. + /// </summary> + internal static class TypeExtensions + { + /// <summary> + /// Returns true if the target type is a value type, including a nullable value type or an enum, or false + /// if it's a reference type (class, delegate, interface - including System.ValueType and System.Enum). + /// </summary> + internal static bool IsValueType(this Type target) + { + return target.GetTypeInfo().IsValueType; + } + + /// <summary> + /// See https://msdn.microsoft.com/en-us/library/system.type.isassignablefrom + /// </summary> + internal static bool IsAssignableFrom(this Type target, Type c) + { + return target.GetTypeInfo().IsAssignableFrom(c.GetTypeInfo()); + } + + /// <summary> + /// Returns a representation of the public property associated with the given name in the given type, + /// including inherited properties or null if there is no such public property. + /// Here, "public property" means a property where either the getter, or the setter, or both, is public. + /// </summary> + internal static PropertyInfo GetProperty(this Type target, string name) + { + // GetDeclaredProperty only returns properties declared in the given type, so we need to recurse. + while (target != null) + { + var typeInfo = target.GetTypeInfo(); + var ret = typeInfo.GetDeclaredProperty(name); + if (ret != null && ((ret.CanRead && ret.GetMethod.IsPublic) || (ret.CanWrite && ret.SetMethod.IsPublic))) + { + return ret; + } + target = typeInfo.BaseType; + } + return null; + } + + /// <summary> + /// Returns a representation of the public method associated with the given name in the given type, + /// including inherited methods. + /// </summary> + /// <remarks> + /// This has a few differences compared with Type.GetMethod in the desktop framework. It will throw + /// if there is an ambiguous match even between a private method and a public one, but it *won't* throw + /// if there are two overloads at different levels in the type hierarchy (e.g. class Base declares public void Foo(int) and + /// class Child : Base declares public void Foo(long)). + /// </remarks> + /// <exception cref="AmbiguousMatchException">One type in the hierarchy declared more than one method with the same name</exception> + internal static MethodInfo GetMethod(this Type target, string name) + { + // GetDeclaredMethod only returns methods declared in the given type, so we need to recurse. + while (target != null) + { + var typeInfo = target.GetTypeInfo(); + var ret = typeInfo.GetDeclaredMethod(name); + if (ret != null && ret.IsPublic) + { + return ret; + } + target = typeInfo.BaseType; + } + return null; + } + } +} |