C# CSharp.EmitContext類代碼示例

 public override void Emit(EmitContext ec)
 {
     if (Value)
         ec.Emit (OpCodes.Ldc_I4_1);
     else
         ec.Emit (OpCodes.Ldc_I4_0);
 }

		public override Expression DoResolve (EmitContext ec)
		{
			//
			// We are born fully resolved
			//
			return this;
		}

 public static void CloseCompilerGeneratedBlock(EmitContext ec)
 {
     if (symwriter != null) {
         int offset = symwriter.GetILOffset (ec.ig);
         symwriter.CloseCompilerGeneratedBlock (offset);
     }
 }

		public override bool Resolve (EmitContext ec)
		{
			expr = expr.Resolve (ec);
			if (expr == null)
				return false;

			Report.Debug (64, "RESOLVE YIELD #1", this, ec, expr, expr.GetType (),
				      ec.CurrentAnonymousMethod, ec.CurrentIterator);

			if (!CheckContext (ec, loc))
				return false;

			Iterator iterator = ec.CurrentIterator;
			if (expr.Type != iterator.OriginalIteratorType) {
				expr = Convert.ImplicitConversionRequired (
					ec, expr, iterator.OriginalIteratorType, loc);
				if (expr == null)
					return false;
			}

			if (!ec.CurrentBranching.CurrentUsageVector.IsUnreachable)
				unwind_protect = ec.CurrentBranching.AddResumePoint (this, loc, out resume_pc);

			return true;
		}

		public override void Emit (EmitContext ec)
		{
			//
			// Emits null pointer
			//
			ec.Emit (OpCodes.Ldc_I4_0);
			ec.Emit (OpCodes.Conv_U);
		}

		public override void Emit (EmitContext ec)
		{
			if (args != null) 
				Invocation.EmitArguments (ec, mi, args);

			ec.ig.Emit (OpCodes.Call, mi);
			return;
		}

		public override void Emit (EmitContext ec)
		{
			ec.ig.Emit (OpCodes.Ldnull);

#if GMCS_SOURCE
			// Only to make verifier happy
			if (TypeManager.IsGenericParameter (type))
				ec.ig.Emit (OpCodes.Unbox_Any, type);
#endif
		}

        public override void Emit(EmitContext ec)
        {
            if (statement != null) {
                statement.EmitStatement (ec);
                ec.Emit (OpCodes.Ret);
                return;
            }

            base.Emit (ec);
        }

		public override void Error_ValueCannotBeConverted (EmitContext ec, Location loc, Type target, bool expl)
		{
			if (!expl && IsLiteral && 
				(TypeManager.IsPrimitiveType (target) || type == TypeManager.decimal_type) &&
				(TypeManager.IsPrimitiveType (type) || type == TypeManager.decimal_type)) {
				Report.Error (31, loc, "Constant value `{0}' cannot be converted to a `{1}'",
					AsString (), TypeManager.CSharpName (target));
			} else {
				base.Error_ValueCannotBeConverted (ec, loc, target, expl);
			}
		}

		public override void Error_ValueCannotBeConverted (EmitContext ec, Location loc, Type t, bool expl)
		{
			if (TypeManager.IsGenericParameter (t)) {
				Report.Error(403, loc,
					"Cannot convert null to the type parameter `{0}' because it could be a value " +
					"type. Consider using `default ({0})' instead", t.Name);
			} else {
				Report.Error(37, loc, "Cannot convert null to `{0}' because it is a value type",
					TypeManager.CSharpName(t));
			}
		}

		public override Expression CreateExpressionTree (EmitContext ec)
		{
			if (expr_tree != null)
				return expr_tree (ec, mg);

			ArrayList args = new ArrayList (arguments.Count + 1);
			args.Add (new Argument (new NullLiteral (loc)));
			args.Add (new Argument (mg.CreateExpressionTree (ec)));
			foreach (Argument a in arguments) {
				args.Add (new Argument (a.Expr.CreateExpressionTree (ec)));
			}

			return CreateExpressionFactoryCall ("Call", args);
		}

        protected override void DoEmit(EmitContext ec)
        {
            if (statement != null) {
                statement.EmitStatement (ec);
                if (unwind_protect)
                    ec.Emit (OpCodes.Leave, ec.CreateReturnLabel ());
                else {
                    ec.Emit (OpCodes.Ret);
                }
                return;
            }

            base.DoEmit (ec);
        }

		static public Expression MakeSimpleCall (EmitContext ec, MethodGroupExpr mg,
							 Expression e, Location loc)
		{
			ArrayList args;
			MethodBase method;
			
			args = new ArrayList (1);
			args.Add (new Argument (e, Argument.AType.Expression));
			method = Invocation.OverloadResolve (ec, (MethodGroupExpr) mg, args, loc);

			if (method == null)
				return null;

			return new StaticCallExpr ((MethodInfo) method, args, loc);
		}

		protected override Parameters ResolveParameters (EmitContext ec, TypeInferenceContext tic, Type delegateType)
		{
			if (!TypeManager.IsDelegateType (delegateType))
				return null;

			AParametersCollection d_params = TypeManager.GetDelegateParameters (delegateType);

			if (HasExplicitParameters) {
				if (!VerifyExplicitParameters (delegateType, d_params, ec.IsInProbingMode))
					return null;

				return Parameters;
			}

			//
			// If L has an implicitly typed parameter list we make implicit parameters explicit
			// Set each parameter of L is given the type of the corresponding parameter in D
			//
			if (!VerifyParameterCompatibility (delegateType, d_params, ec.IsInProbingMode))
				return null;

			Type [] ptypes = new Type [Parameters.Count];
			for (int i = 0; i < d_params.Count; i++) {
				// D has no ref or out parameters
				if ((d_params.FixedParameters [i].ModFlags & Parameter.Modifier.ISBYREF) != 0)
					return null;

				Type d_param = d_params.Types [i];

#if MS_COMPATIBLE
				// Blablabla, because reflection does not work with dynamic types
				if (d_param.IsGenericParameter)
					d_param = delegateType.GetGenericArguments () [d_param.GenericParameterPosition];
#endif
				//
				// When type inference context exists try to apply inferred type arguments
				//
				if (tic != null) {
					d_param = tic.InflateGenericArgument (d_param);
				}

				ptypes [i] = d_param;
				((ImplicitLambdaParameter) Parameters.FixedParameters [i]).Type = d_param;
			}

			Parameters.Types = ptypes;
			return Parameters;
		}

		public override bool GetAttributableValue (EmitContext ec, Type value_type, out object value)
		{
			if (value_type == TypeManager.object_type) {
				value = GetTypedValue ();
				return true;
			}

			Constant c = ImplicitConversionRequired (ec, value_type, loc);
			if (c == null) {
				value = null;
				return false;
			}

			value = c.GetTypedValue ();
			return true;
		}