与Reflection.Emit的动态创建一个类。我被困 [英] Create a class dynamically with Reflection.Emit. I got stuck
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问题描述
有一个了解在运行时创建的类型，我发现很神奇。 我的目标是创建一个类：
[DelimitedRecord（）]
公共类Person
{
[FieldOrder（0）]
私人字符串的firstName;
[FieldOrder（1）]
私人字符串的lastName;
公共字符串名字
{
{返回的firstName; }
集合{的firstName =价值; }
}
公共字符串名字
{
{返回的lastName; }
集合{lastName的=值; }
}
}
我这样做：
//创建构建器
的AssemblyName组件=新的AssemblyName（FileHelpersTests）;
AppDomain中的AppDomain = System.Threading.Thread.GetDomain（）;
AssemblyBuilder assemblyBuilder = appDomain.DefineDynamicAssembly（组装，AssemblyBuilderAccess.Run）;
ModuleBuilder moduleBuilder = assemblyBuilder.DefineDynamicModule（assembly.Name）;
//创建类
TypeBuilder typeBuilder = moduleBuilder.DefineType（人，TypeAttributes.Public | TypeAttributes.AutoClass | TypeAttributes.AnsiClass |
TypeAttributes.BeforeFieldInit的typeof（System.Object中））;
//创建分隔符属性
//创建名字字段
FieldBuilder firstNameField = typeBuilder.DefineField（名字的typeof（System.String），FieldAttributes.Private）;
//创建中的firstName属性[FieldOrder（0）]
//创建名字属性
PropertyBuilder firstNameProperty = typeBuilder.DefineProperty（名字，PropertyAttributes.HasDefault的typeof（System.String），NULL）;
//创建名字消气
MethodBuilder firstNamePropertyGetter = typeBuilder.DefineMethod（get_FirstName，MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig的typeof（System.String），Type.EmptyTypes）;
的ILGenerator firstNamePropertyGetterIL = firstNamePropertyGetter.GetILGenerator（）;
firstNamePropertyGetterIL.Emit（欧普codes.Ldarg_0）;
firstNamePropertyGetterIL.Emit（欧普codes.Ldfld，firstNameField）;
firstNamePropertyGetterIL.Emit（欧普codes.Ret）;
//创建名字二传手
MethodBuilder firstNamePropertySetter = typeBuilder.DefineMethod（set_FirstName，MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig，空，新类型[] {typeof运算（System.String）}）;
的ILGenerator firstNamePropertySetterIL = firstNamePropertySetter.GetILGenerator（）;
firstNamePropertySetterIL.Emit（欧普codes.Ldarg_0）;
firstNamePropertySetterIL.Emit（欧普codes.Ldarg_1）;
firstNamePropertySetterIL.Emit（欧普codes.Stfld，firstNameField）;
firstNamePropertySetterIL.Emit（欧普codes.Ret）;
//分配getter和setter
firstNameProperty.SetGetMethod（firstNamePropertyGetter）;
firstNameProperty.SetSetMethod（firstNamePropertySetter）;
//创建姓氏字段
FieldBuilder lastNameField = typeBuilder.DefineField（姓氏的typeof（System.String），FieldAttributes.Private）;
//创建姓氏属性[FieldOrder（1）]
//创建名字属性
PropertyBuilder lastNameProperty = typeBuilder.DefineProperty（姓氏，PropertyAttributes.HasDefault的typeof（System.String），NULL）;
//创建姓氏消气
MethodBuilder lastNamePropertyGetter = typeBuilder.DefineMethod（get_LastName，MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig的typeof（System.String），Type.EmptyTypes）;
的ILGenerator lastNamePropertyGetterIL = lastNamePropertyGetter.GetILGenerator（）;
lastNamePropertyGetterIL.Emit（欧普codes.Ldarg_0）;
lastNamePropertyGetterIL.Emit（欧普codes.Ldfld，lastNameField）;
lastNamePropertyGetterIL.Emit（欧普codes.Ret）;
//创建名字二传手
MethodBuilder lastNamePropertySetter = typeBuilder.DefineMethod（set_FirstName，MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig，空，新类型[] {typeof运算（System.String）}）;
的ILGenerator lastNamePropertySetterIL = lastNamePropertySetter.GetILGenerator（）;
lastNamePropertySetterIL.Emit（欧普codes.Ldarg_0）;
lastNamePropertySetterIL.Emit（欧普codes.Ldarg_1）;
lastNamePropertySetterIL.Emit（欧普codes.Stfld，lastNameField）;
lastNamePropertySetterIL.Emit（欧普codes.Ret）;
//分配getter和setter
lastNameProperty.SetGetMethod（lastNamePropertyGetter）;
lastNameProperty.SetSetMethod（lastNamePropertySetter）;
而创建这些属性我卡住了：
- 在那个在一流水平
- 在那个在现场级
这是什么ILDASM显示当我点击
-
构造
的.class众汽车ANSI beforefieldinit FileHelpersTests.Person 扩展[mscorlib程序] System.Object的 { .custom实例无效[FileHelpers] FileHelpers.DelimitedRecordAttribute ::。ctor的（字符串）=（01 00 01 2C 00 00）// ... .. 类FileHelpersTests.Person的} //结束 -
名字字段
点域私人字符串的firstName .custom实例无效[FileHelpers] FileHelpers.FieldOrderAttribute ::。ctor的（INT32）=（01 00 00 00 00 00 00 00）
解决方案
我做了它的工作：
//创建分隔符属性
键入[] attributeParams =新类型[] {typeof运算（字符串）};
ConstructorInfo classCtorInfo = typeof运算（DelimitedRecordAttribute）.GetConstructor（attributeParams）;
CustomAttributeBuilder attributeBuilder =新CustomAttributeBuilder（classCtorInfo，新的对象[] {，}）;
typeBuilder.SetCustomAttribute（attributeBuilder）;
这将完成这项工作的字段属性：
//创建的firstName属性[FieldOrder（0）]
键入[] firstNameFieldOrderAttributeParams =新类型[] {typeof运算（INT）};
ConstructorInfo firstNameFieldOrderAttrInfo = typeof运算（FieldOrderAttribute）.GetConstructor（firstNameFieldOrderAttributeParams）;
CustomAttributeBuilder firstNameFieldOrderAttributeBuilder =新CustomAttributeBuilder（firstNameFieldOrderAttrInfo，新的对象[] {0}）;
firstNameField.SetCustomAttribute（firstNameFieldOrderAttributeBuilder）;
A read about creating types at runtime and i found it amazing. My goal is to create this class:
[DelimitedRecord(",")]
public class Person
{
[FieldOrder(0)]
private string firstName;
[FieldOrder(1)]
private string lastName;
public string FirstName
{
get { return firstName; }
set { firstName = value; }
}
public string LastName
{
get { return lastName; }
set { lastName = value; }
}
}
I did this:
//create the builder
AssemblyName assembly = new AssemblyName("FileHelpersTests");
AppDomain appDomain = System.Threading.Thread.GetDomain();
AssemblyBuilder assemblyBuilder = appDomain.DefineDynamicAssembly(assembly, AssemblyBuilderAccess.Run);
ModuleBuilder moduleBuilder = assemblyBuilder.DefineDynamicModule(assembly.Name);
//create the class
TypeBuilder typeBuilder = moduleBuilder.DefineType("Person", TypeAttributes.Public | TypeAttributes.AutoClass | TypeAttributes.AnsiClass |
TypeAttributes.BeforeFieldInit, typeof(System.Object));
//create the Delimiter attribute
//create the firstName field
FieldBuilder firstNameField = typeBuilder.DefineField("firstName", typeof(System.String), FieldAttributes.Private);
//create the firstName attribute [FieldOrder(0)]
//create the FirstName property
PropertyBuilder firstNameProperty = typeBuilder.DefineProperty("FirstName", PropertyAttributes.HasDefault, typeof(System.String), null);
//create the FirstName Getter
MethodBuilder firstNamePropertyGetter = typeBuilder.DefineMethod("get_FirstName", MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig, typeof(System.String), Type.EmptyTypes);
ILGenerator firstNamePropertyGetterIL = firstNamePropertyGetter.GetILGenerator();
firstNamePropertyGetterIL.Emit(OpCodes.Ldarg_0);
firstNamePropertyGetterIL.Emit(OpCodes.Ldfld, firstNameField);
firstNamePropertyGetterIL.Emit(OpCodes.Ret);
//create the FirstName Setter
MethodBuilder firstNamePropertySetter = typeBuilder.DefineMethod("set_FirstName", MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig, null, new Type[] { typeof(System.String) });
ILGenerator firstNamePropertySetterIL = firstNamePropertySetter.GetILGenerator();
firstNamePropertySetterIL.Emit(OpCodes.Ldarg_0);
firstNamePropertySetterIL.Emit(OpCodes.Ldarg_1);
firstNamePropertySetterIL.Emit(OpCodes.Stfld, firstNameField);
firstNamePropertySetterIL.Emit(OpCodes.Ret);
//assign getter and setter
firstNameProperty.SetGetMethod(firstNamePropertyGetter);
firstNameProperty.SetSetMethod(firstNamePropertySetter);
//create the lastName field
FieldBuilder lastNameField = typeBuilder.DefineField("lastName", typeof(System.String), FieldAttributes.Private);
//create the lastName attribute [FieldOrder(1)]
//create the LastName property
PropertyBuilder lastNameProperty = typeBuilder.DefineProperty("LastName", PropertyAttributes.HasDefault, typeof(System.String), null);
//create the LastName Getter
MethodBuilder lastNamePropertyGetter = typeBuilder.DefineMethod("get_LastName", MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig, typeof(System.String), Type.EmptyTypes);
ILGenerator lastNamePropertyGetterIL = lastNamePropertyGetter.GetILGenerator();
lastNamePropertyGetterIL.Emit(OpCodes.Ldarg_0);
lastNamePropertyGetterIL.Emit(OpCodes.Ldfld, lastNameField);
lastNamePropertyGetterIL.Emit(OpCodes.Ret);
//create the FirstName Setter
MethodBuilder lastNamePropertySetter = typeBuilder.DefineMethod("set_FirstName", MethodAttributes.Public | MethodAttributes.SpecialName |
MethodAttributes.HideBySig, null, new Type[] { typeof(System.String) });
ILGenerator lastNamePropertySetterIL = lastNamePropertySetter.GetILGenerator();
lastNamePropertySetterIL.Emit(OpCodes.Ldarg_0);
lastNamePropertySetterIL.Emit(OpCodes.Ldarg_1);
lastNamePropertySetterIL.Emit(OpCodes.Stfld, lastNameField);
lastNamePropertySetterIL.Emit(OpCodes.Ret);
//assign getter and setter
lastNameProperty.SetGetMethod(lastNamePropertyGetter);
lastNameProperty.SetSetMethod(lastNamePropertySetter);
I got stuck while creating those attributes:
- The one at class level
- The one at field level
This is what ILDASM shows when i click
The constructor
.class public auto ansi beforefieldinit FileHelpersTests.Person extends [mscorlib]System.Object { .custom instance void [FileHelpers]FileHelpers.DelimitedRecordAttribute::.ctor(string) = ( 01 00 01 2C 00 00 ) // ...,.. } // end of class FileHelpersTests.PersonThe firstName field
.field private string firstName .custom instance void [FileHelpers]FileHelpers.FieldOrderAttribute::.ctor(int32) = ( 01 00 00 00 00 00 00 00 )
解决方案
I made it work:
//create the Delimiter attribute
Type[] attributeParams = new Type[] { typeof(string) };
ConstructorInfo classCtorInfo = typeof(DelimitedRecordAttribute).GetConstructor(attributeParams);
CustomAttributeBuilder attributeBuilder = new CustomAttributeBuilder(classCtorInfo, new object[] { ";" });
typeBuilder.SetCustomAttribute(attributeBuilder);
This would do the job for the field attributes:
//create the firstName attribute [FieldOrder(0)]
Type[] firstNameFieldOrderAttributeParams = new Type[] { typeof(int) };
ConstructorInfo firstNameFieldOrderAttrInfo = typeof(FieldOrderAttribute).GetConstructor(firstNameFieldOrderAttributeParams);
CustomAttributeBuilder firstNameFieldOrderAttributeBuilder = new CustomAttributeBuilder(firstNameFieldOrderAttrInfo, new object[] { 0 });
firstNameField.SetCustomAttribute(firstNameFieldOrderAttributeBuilder);
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