Исходный код вики Сценарии

Редактировал(а) Alexandr Fokin 2025/05/13 13:04

version	line-number	content
2.4	1	\|(% style="width:394px" %)Компиляция дерева в делегат\|(% style="width:1090px" %){{code language="c#"}}Expression
1.2	2	.Lambda(expressionValiarble)
1.4	3	.Compile();{{/code}}
2.4	4	\|(% style="width:394px" %)[[Простое копирование свойств одного класса в другой>>doc:Разработка.NET.C#.Рантайм и типы.Expression tree \| Деревья выражений.Сценарии.Простое копирование свойств одного класса в другой.WebHome]]\|(% style="width:1090px" %)
	5	\|(% style="width:394px" %)[[Маппинг на основе выражения доступа к свойству>>doc:.Маппинг на основе выражения доступа к свойству.WebHome]]\|(% style="width:1090px" %)
	6	\|(% style="width:394px" %)Вызов делегата при построении EpressionTree\|(% style="width:1090px" %)Expression Trees and Invoking a Delegate
1.4	7	[[https:~~/~~/stackoverflow.com/questions/2215712/expression-trees-and-invoking-a-delegate>>url:https://stackoverflow.com/questions/2215712/expression-trees-and-invoking-a-delegate]]
2.4	8	\|(% style="width:394px" %)Объявлений локальной переменной в блоке
	9	(без передачи извне)\|(% style="width:1090px" %)(((
1.4	10	переменная типа указана из области видимости, но не определена
	11	[[https:~~/~~/question-it.com/questions/717473/peremennaja-tipa-ukazana-iz-oblasti-vidimosti-no-ne-opredelena>>url:https://question-it.com/questions/717473/peremennaja-tipa-ukazana-iz-oblasti-vidimosti-no-ne-opredelena]]
	12	)))
2.4	13	\|(% style="width:394px" %) \|(% style="width:1090px" %)(((
1.4	14	How do I set a field value in an C# Expression tree?
	15	[[https:~~/~~/stackoverflow.com/questions/321650/how-do-i-set-a-field-value-in-an-c-sharp-expression-tree>>https://stackoverflow.com/questions/321650/how-do-i-set-a-field-value-in-an-c-sharp-expression-tree]]
	16	)))
2.10	17	\|(% style="width:394px" %)Типизированый вызов конструктора\|(% style="width:1090px" %){{code language="c#"}}var constructorInfo = type.GetConstructors().First(e => e.Attributes.HasFlag(MethodAttributes.Public));
2.3	18	var constructorParameter1 = Expression.Parameter(typeof(bool));
	19	var constructorExp = Expression.New(constructorInfo, constructorParameter1);
1.2	20
2.3	21	// Func<bool, object> or Func<bool, T>
	22	var constructorDelegate = Expression
	23	.Lambda<Func<bool, object>>(
	24	constructorExp,
2.5	25	constructorParameter1
2.3	26	)
2.4	27	.Compile();{{/code}}(((
	28	How do you call a constructor via an expression tree on an existing object?
	29	[[https:~~/~~/stackoverflow.com/questions/16363838/how-do-you-call-a-constructor-via-an-expression-tree-on-an-existing-object>>https://stackoverflow.com/questions/16363838/how-do-you-call-a-constructor-via-an-expression-tree-on-an-existing-object]]
	30	)))
2.10	31	\|(% style="width:394px" %)Нетипизированый вызов\|(% style="width:1090px" %)(((
	32	\|{{code language="c#"}}public delegate object ConstructorDelegate(object[]? Args);
	33
	34	public static ConstructorDelegate GetConstructorWithArgsDelegate(
	35	ConstructorInfo constructorInfo)
	36	{
2.12	37	ParameterExpression constructorParameters = Expression.Parameter(typeof(object?[]));
	38
	39	Expression[] parameterExpressions;
	40	{
	41	ParameterInfo[] parametersInfos = constructorInfo.GetParameters();
	42	parameterExpressions = new Expression[parametersInfos.Length];
	43
	44	for (int i = 0; i < parametersInfos.Length; i++)
	45	{
	46	ConstantExpression ithIndex = Expression.Constant(i);
	47	BinaryExpression ithParameter = Expression.ArrayIndex(
	48	constructorParameters,
	49	ithIndex);
	50	UnaryExpression unboxedIthParameter = Expression.Convert(
	51	ithParameter,
	52	parametersInfos[i].ParameterType
2.10	53	);
2.12	54	parameterExpressions[i] = unboxedIthParameter;
	55	}
	56	}
	57
	58	NewExpression constructorCallExp = Expression.New(
	59	constructorInfo,
	60	parameterExpressions);
	61
	62	var convertResultExp = Expression.Convert(
	63	constructorCallExp,
	64	typeof(object)
	65	);
	66
	67	var constructorHandler = Expression
	68	.Lambda<ConstructorDelegate>(
	69	convertResultExp,
	70	constructorParameters
	71	)
	72	.Compile();
	73
	74	return constructorHandler;
	75	}{{/code}}\|{{code language="c#"}}object Func<object[]>{{/code}}(((
	76	C# Expression tree: object array to Expression.New() parameters
2.10	77	[[https:~~/~~/stackoverflow.com/questions/67968927/c-sharp-expression-tree-object-array-to-expression-new-parameters>>https://stackoverflow.com/questions/67968927/c-sharp-expression-tree-object-array-to-expression-new-parameters]]
2.12	78	)))
2.10	79	\|{{code language="c#"}}public delegate object? MethodDelegate(object instance, object[]? Args);
	80
	81	public static MethodDelegate GetMethodWithArgsDelegate(
	82	MethodInfo methodInfo,
	83	Type instanceType)
	84	{
2.12	85	ParameterExpression instanceParameter = Expression.Parameter(typeof(object));
	86	ParameterExpression methodParameters = Expression.Parameter(typeof(object?[]));
	87
	88	Expression instanceExp;
	89	Expression[] parameterExpressions;
	90	{
	91	instanceExp = Expression.Convert(instanceParameter, instanceType);
	92
	93	ParameterInfo[] parametersInfos = methodInfo.GetParameters();
	94	parameterExpressions = new Expression[parametersInfos.Length];
	95
	96	for (int i = 0; i < parametersInfos.Length; i++)
	97	{
	98	ConstantExpression ithIndex = Expression.Constant(i);
	99	BinaryExpression ithParameter = Expression.ArrayIndex(
	100	methodParameters,
	101	ithIndex);
	102	UnaryExpression unboxedIthParameter = Expression.Convert(
	103	ithParameter,
	104	parametersInfos[i].ParameterType
2.10	105	);
2.12	106	parameterExpressions[i] = unboxedIthParameter;
	107	}
	108	}
	109
	110	var callExpression = Expression.Call(
	111	instanceExp,
	112	methodInfo,
	113	parameterExpressions
	114	);
	115
	116	var convertResultExp = Expression.Convert(
	117	callExpression,
	118	typeof(object)
	119	);
	120
	121	var callHandler = Expression
	122	.Lambda<MethodDelegate>(
	123	convertResultExp,
	124	instanceParameter,
	125	methodParameters
	126	)
	127	.Compile();
	128
	129	return callHandler;
	130	}{{/code}}\|{{code language="c#"}}object? Func<object, object[]>{{/code}}
2.10	131
	132
	133	)))
2.9	134	\|(% style="width:394px" %)[[Generic enum to int>>doc:.Generic enum to int.WebHome]]\|(% style="width:1090px" %)
2.3	135
1.5	136	==== ====
1.2	137
1.5	138	==== ====
1.2	139
1.5	140	==== ====

Исходный код вики Сценарии

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