C# ISymbol.HasAttribute方法代码示例

		/// <summary>
		///   Checks whether the <paramref name="symbol" />'s implementing member for <paramref name="interfaceMember" /> has the
		///   correct port kind.
		/// </summary>
		/// <param name="context">The context in which the analysis should be performed.</param>
		/// <param name="symbol">The symbol that should be analyzed.</param>
		/// <param name="compilation">The compilation the symbol is declared in.</param>
		/// <param name="interfaceMember">The interface member that should be checked.</param>
		private static void CheckMember(SymbolAnalysisContext context, ITypeSymbol symbol, Compilation compilation, ISymbol interfaceMember)
		{
			var implementingMember = symbol.FindImplementationForInterfaceMember(interfaceMember);

			var interfaceIsRequired = interfaceMember.HasAttribute<RequiredAttribute>(compilation);
			var interfaceIsProvided = interfaceMember.HasAttribute<ProvidedAttribute>(compilation);

			var implementationIsRequired = implementingMember.HasAttribute<RequiredAttribute>(compilation) || implementingMember.IsExtern;
			var implementationIsProvided = implementingMember.HasAttribute<ProvidedAttribute>(compilation) || !implementingMember.IsExtern;

			// If we can't uniquely classify the port kind of either the interface member or the implementation, 
			// there is another problem that another analyzer deals with. So let's just ignore it here.
			if ((interfaceIsRequired && interfaceIsProvided) || (implementationIsProvided && implementationIsRequired))
				return;

			var location = implementingMember.ContainingType.Equals(symbol) ? implementingMember : symbol;
			if (interfaceIsRequired && !implementationIsRequired)
			{
				_requiredPortImplementedAsProvidedPort.Emit(context, location,
					implementingMember.ToDisplayString(), interfaceMember.ToDisplayString());
			}

			if (interfaceIsProvided && !implementationIsProvided)
			{
				_providedPortImplementedAsRequiredPort.Emit(context, location,
					implementingMember.ToDisplayString(), interfaceMember.ToDisplayString());
			}
		}

 private static bool HasNotNullAttribute(ISymbol symbol)
 {
     return symbol.HasAttribute("NotNullAttribute");
 }