Изменения документа Сценарии
Редактировал(а) Alexandr Fokin 2025/05/13 13:04
От версии 2.8
отредактировано Alexandr Fokin
на 2023/10/27 13:49
на 2023/10/27 13:49
Изменить комментарий:
К данной версии нет комментариев
К версии 2.11
отредактировано Alexandr Fokin
на 2025/05/13 13:02
на 2025/05/13 13:02
Изменить комментарий:
К данной версии нет комментариев
Сводка
-
Свойства страницы (1 изменено, 0 добавлено, 0 удалено)
Подробности
- Свойства страницы
-
- Содержимое
-
... ... @@ -14,7 +14,7 @@ 14 14 How do I set a field value in an C# Expression tree? 15 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 16 ))) 17 -|(% style="width:394px" %) Вызов конструктора|(% style="width:1090px" %){{code language="c#"}}var constructorInfo = type.GetConstructors().First(e => e.Attributes.HasFlag(MethodAttributes.Public));17 +|(% style="width:394px" %)Типизированый вызов конструктора|(% style="width:1090px" %){{code language="c#"}}var constructorInfo = type.GetConstructors().First(e => e.Attributes.HasFlag(MethodAttributes.Public)); 18 18 var constructorParameter1 = Expression.Parameter(typeof(bool)); 19 19 var constructorExp = Expression.New(constructorInfo, constructorParameter1); 20 20 ... ... @@ -28,9 +28,109 @@ 28 28 How do you call a constructor via an expression tree on an existing object? 29 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 30 ))) 31 -|(% style="width:394px" %) Genericenum to int|(% style="width:1090px" %)How do I cast a generic enum to int?32 - [[https:~~/~~/stackoverflow.com/questions/16960555/how-do-i-cast-a-generic-enum-to-int>>https://stackoverflow.com/questions/16960555/how-do-i-cast-a-generic-enum-to-int]]31 +|(% style="width:394px" %)Нетипизированый вызов|(% style="width:1090px" %)((( 32 +|{{code language="c#"}}public delegate object ConstructorDelegate(object[]? Args); 33 33 34 +public static ConstructorDelegate GetConstructorWithArgsDelegate( 35 + ConstructorInfo constructorInfo) 36 +{ 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 53 + ); 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}}|C# Expression tree: object array to Expression.New() parameters 76 +[[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]] 77 +|{{code language="c#"}}public delegate object? MethodDelegate(object instance, object[]? Args); 78 + 79 +public static MethodDelegate GetMethodWithArgsDelegate( 80 + MethodInfo methodInfo, 81 + Type instanceType) 82 +{ 83 +ParameterExpression instanceParameter = Expression.Parameter(typeof(object)); 84 +ParameterExpression methodParameters = Expression.Parameter(typeof(object?[])); 85 + 86 +Expression instanceExp; 87 +Expression[] parameterExpressions; 88 +{ 89 + instanceExp = Expression.Convert(instanceParameter, instanceType); 90 + 91 + ParameterInfo[] parametersInfos = methodInfo.GetParameters(); 92 + parameterExpressions = new Expression[parametersInfos.Length]; 93 + 94 + for (int i = 0; i < parametersInfos.Length; i++) 95 + { 96 + ConstantExpression ithIndex = Expression.Constant(i); 97 + BinaryExpression ithParameter = Expression.ArrayIndex( 98 + methodParameters, 99 + ithIndex); 100 + UnaryExpression unboxedIthParameter = Expression.Convert( 101 + ithParameter, 102 + parametersInfos[i].ParameterType 103 + ); 104 + parameterExpressions[i] = unboxedIthParameter; 105 + } 106 +} 107 + 108 +var callExpression = Expression.Call( 109 + instanceExp, 110 + methodInfo, 111 + parameterExpressions 112 + ); 113 + 114 +var convertResultExp = Expression.Convert( 115 + callExpression, 116 + typeof(object) 117 + ); 118 + 119 +var callHandler = Expression 120 + .Lambda<MethodDelegate>( 121 + convertResultExp, 122 + instanceParameter, 123 + methodParameters 124 + ) 125 + .Compile(); 126 + 127 +return callHandler; 128 +}{{/code}}| 129 + 130 + 131 +))) 132 +|(% style="width:394px" %)[[Generic enum to int>>doc:.Generic enum to int.WebHome]]|(% style="width:1090px" %) 133 + 34 34 ==== ==== 35 35 36 36 ==== ====