Erstellen Sie mit Reflection.Emit dynamisch eine Klasse. Ich blieb stecken
Eine Lektüre über das Erstellen von Typen zur Laufzeit und ich fand es erstaunlich. Mein Ziel ist es, diese Klasse zu erstellen:
[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; }
}
}
Ich tat dies:
//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);
Ich bin beim Erstellen dieser Attribute hängen geblieben:
Der auf KlassenebeneDie auf FeldebeneDies ist, was ILDASM zeigt, wenn ich klicke
Der Erbauer
.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.Person
Das firstName-Feld
.field private string firstName
.custom instance void [FileHelpers]FileHelpers.FieldOrderAttribute::.ctor(int32) = ( 01 00 00 00 00 00 00 00 )