ParameterBuilder 类

定义

命名空间:: System.Reflection.Emit

程序集:: netstandard.dll, System.Reflection.Emit.ILGeneration.dll

程序集:: System.Reflection.Emit.ILGeneration.dll

程序集:: mscorlib.dll

程序集:: netstandard.dll

Source:: ParameterBuilder.cs

Source:: ParameterBuilder.cs

Source:: ParameterBuilder.cs

Source:: ParameterBuilder.cs

重要

一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。

创建或关联参数信息。

public ref class ParameterBuilder abstract

public ref class ParameterBuilder

public ref class ParameterBuilder : System::Runtime::InteropServices::_ParameterBuilder

public abstract class ParameterBuilder

public class ParameterBuilder

[System.Runtime.InteropServices.ClassInterface(System.Runtime.InteropServices.ClassInterfaceType.None)]
public class ParameterBuilder : System.Runtime.InteropServices._ParameterBuilder

[System.Runtime.InteropServices.ClassInterface(System.Runtime.InteropServices.ClassInterfaceType.None)]
[System.Runtime.InteropServices.ComVisible(true)]
public class ParameterBuilder : System.Runtime.InteropServices._ParameterBuilder

type ParameterBuilder = class

[<System.Runtime.InteropServices.ClassInterface(System.Runtime.InteropServices.ClassInterfaceType.None)>]
type ParameterBuilder = class
    interface _ParameterBuilder

[<System.Runtime.InteropServices.ClassInterface(System.Runtime.InteropServices.ClassInterfaceType.None)>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type ParameterBuilder = class
    interface _ParameterBuilder

Public MustInherit Class ParameterBuilder

Public Class ParameterBuilder

Public Class ParameterBuilder
Implements _ParameterBuilder

继承: Object
ParameterBuilder

属性: ClassInterfaceAttribute ComVisibleAttribute

实现: _ParameterBuilder

示例

以下示例演示如何使用 ParameterBuilder通过引用传递参数创建动态方法。


using System;
using System.Threading;
using System.Reflection;
using System.Reflection.Emit;

class ParamBuilderDemo

{

   public static Type BuildCustomerDataType()
   {

    AppDomain myDomain = Thread.GetDomain();
    AssemblyName myAsmName = new AssemblyName();
    myAsmName.Name = "MyDynamicAssembly";

    AssemblyBuilder myAsmBuilder = myDomain.DefineDynamicAssembly(myAsmName,
                        AssemblyBuilderAccess.Run);

    ModuleBuilder myModBuilder = myAsmBuilder.DefineDynamicModule("MyMod");

    TypeBuilder myTypeBuilder = myModBuilder.DefineType("CustomerData",
                        TypeAttributes.Public);

    FieldBuilder customerNameBldr = myTypeBuilder.DefineField("customerName",
                            typeof(string),
                            FieldAttributes.Private);
    FieldBuilder acctIDBldr = myTypeBuilder.DefineField("acctID",
                            typeof(string),
                            FieldAttributes.Private);
    FieldBuilder balanceAmtBldr = myTypeBuilder.DefineField("balanceAmt",
                            typeof(double),
                            FieldAttributes.Private);
                                
    ConstructorBuilder myCtorBuilder = myTypeBuilder.DefineConstructor(
                            MethodAttributes.Public,
                            CallingConventions.HasThis,
                            new Type[] { typeof(string),
                                     typeof(string),
                                     typeof(double) });

    ILGenerator ctorIL = myCtorBuilder.GetILGenerator();

    Type objType = Type.GetType("System.Object");
        ConstructorInfo objCtor = objType.GetConstructor(new Type[] {});

    ctorIL.Emit(OpCodes.Ldarg_0);
    ctorIL.Emit(OpCodes.Call, objCtor);

    ctorIL.Emit(OpCodes.Ldarg_0);
    ctorIL.Emit(OpCodes.Ldarg_1);
    ctorIL.Emit(OpCodes.Stfld, customerNameBldr);

    ctorIL.Emit(OpCodes.Ldarg_0);
    ctorIL.Emit(OpCodes.Ldarg_2);
    ctorIL.Emit(OpCodes.Stfld, acctIDBldr);

    ctorIL.Emit(OpCodes.Ldarg_0);
    ctorIL.Emit(OpCodes.Ldarg_3);
    ctorIL.Emit(OpCodes.Stfld, balanceAmtBldr);

    ctorIL.Emit(OpCodes.Ret);

    // This method will take an amount from a static pool and add it to the balance.

    // Note that we are passing the first parameter, fundsPool, by reference. Therefore,
    // we need to inform the MethodBuilder to expect a ref, by declaring the first
    // parameter's type to be System.Double& (a reference to a double).

    MethodBuilder myMthdBuilder = myTypeBuilder.DefineMethod("AddFundsFromPool",
                        MethodAttributes.Public,
                        typeof(double),
                        new Type[] { Type.GetType("System.Double&"),
                                 typeof(double) });

    ParameterBuilder poolRefBuilder = myMthdBuilder.DefineParameter(1,
                        ParameterAttributes.Out,
                        "fundsPool");

    ParameterBuilder amountFromPoolBuilder = myMthdBuilder.DefineParameter(2,
                        ParameterAttributes.In,
                            "amountFromPool");

    ILGenerator mthdIL = myMthdBuilder.GetILGenerator();

    mthdIL.Emit(OpCodes.Ldarg_1);
    mthdIL.Emit(OpCodes.Ldarg_1);
    mthdIL.Emit(OpCodes.Ldind_R8);
    mthdIL.Emit(OpCodes.Ldarg_2);
    mthdIL.Emit(OpCodes.Sub);

    mthdIL.Emit(OpCodes.Stind_R8);

    mthdIL.Emit(OpCodes.Ldarg_0);
    mthdIL.Emit(OpCodes.Ldarg_0);
    mthdIL.Emit(OpCodes.Ldfld, balanceAmtBldr);
    mthdIL.Emit(OpCodes.Ldarg_2);
    mthdIL.Emit(OpCodes.Add);

    mthdIL.Emit(OpCodes.Stfld, balanceAmtBldr);

    mthdIL.Emit(OpCodes.Ldarg_0);
    mthdIL.Emit(OpCodes.Ldfld, balanceAmtBldr);
    mthdIL.Emit(OpCodes.Ret);

    return myTypeBuilder.CreateType();
   }

   public static void Main()
   {
    Type custType = null;
    object custObj = null;

    Type[] custArgTypes = new Type[] {typeof(string), typeof(string), typeof(double)};
    
    // Call the method to build our dynamic class.

    custType = BuildCustomerDataType();

    Console.WriteLine("---");

    ConstructorInfo myCustCtor = custType.GetConstructor(custArgTypes);
    double initialBalance = 100.00;
    custObj = myCustCtor.Invoke(new object[] { "Joe Consumer",
                           "5678-XYZ",
                           initialBalance });

    MemberInfo[] myMemberInfo = custType.GetMember("AddFundsFromPool");

    double thePool = 1000.00;
    Console.WriteLine("The pool is currently ${0}", thePool);
    Console.WriteLine("The original balance of the account instance is ${0}",
                            initialBalance);

    double amountFromPool = 50.00;
    Console.WriteLine("The amount to be subtracted from the pool and added " +
              "to the account is ${0}", amountFromPool);
    
    Console.WriteLine("---");
    Console.WriteLine("Calling {0} ...", myMemberInfo[0].ToString());
    Console.WriteLine("---");

    object[] passMe = new object[] { thePool, amountFromPool };
    Console.WriteLine("The new balance in the account instance is ${0}",
                    custType.InvokeMember("AddFundsFromPool",
                    BindingFlags.InvokeMethod,
                    null, custObj, passMe));
    thePool = (double)passMe[0];
    Console.WriteLine("The new amount in the pool is ${0}", thePool);
   }
}


Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit

 _

Class ParamBuilderDemo
   
   Public Shared Function BuildCustomerDataType() As Type
      
      Dim myDomain As AppDomain = Thread.GetDomain()
      Dim myAsmName As New AssemblyName()
      myAsmName.Name = "MyDynamicAssembly"
      
      Dim myAsmBuilder As AssemblyBuilder = myDomain.DefineDynamicAssembly(myAsmName, _
                        AssemblyBuilderAccess.Run)
      
      Dim myModBuilder As ModuleBuilder = myAsmBuilder.DefineDynamicModule("MyMod")
      
      Dim myTypeBuilder As TypeBuilder = myModBuilder.DefineType("CustomerData", TypeAttributes.Public)
      
      Dim customerNameBldr As FieldBuilder = myTypeBuilder.DefineField("customerName", _
                                GetType(String), _
                                FieldAttributes.Private)
      Dim acctIDBldr As FieldBuilder = myTypeBuilder.DefineField("acctID", _
                                GetType(String), _
                                FieldAttributes.Private)
      Dim balanceAmtBldr As FieldBuilder = myTypeBuilder.DefineField("balanceAmt", _
                                GetType(Double), _
                                FieldAttributes.Private)
      
      Dim myCtorBuilder As ConstructorBuilder = myTypeBuilder.DefineConstructor(MethodAttributes.Public, _
                                CallingConventions.HasThis, _
                                New Type() {GetType(String), _
                                        GetType(String), _
                                        GetType(Double)})
      
      
      Dim ctorIL As ILGenerator = myCtorBuilder.GetILGenerator()
      
      Dim objType As Type = Type.GetType("System.Object")
      Dim objCtor As ConstructorInfo = objType.GetConstructor(New Type(){})
      
      ctorIL.Emit(OpCodes.Ldarg_0)
      ctorIL.Emit(OpCodes.Call, objCtor)
      
      ctorIL.Emit(OpCodes.Ldarg_0)
      ctorIL.Emit(OpCodes.Ldarg_1)
      ctorIL.Emit(OpCodes.Stfld, customerNameBldr)
      
      ctorIL.Emit(OpCodes.Ldarg_0)
      ctorIL.Emit(OpCodes.Ldarg_2)
      ctorIL.Emit(OpCodes.Stfld, acctIDBldr)
      
      ctorIL.Emit(OpCodes.Ldarg_0)
      ctorIL.Emit(OpCodes.Ldarg_3)
      ctorIL.Emit(OpCodes.Stfld, balanceAmtBldr)
      
      ctorIL.Emit(OpCodes.Ret)
      
      ' This method will take an amount from a static pool and add it to the balance.
      ' Note that we are passing the first parameter, fundsPool, by reference. Therefore,
      ' we need to inform the MethodBuilder to expect a ref, by declaring the first
      ' parameter's type to be System.Double& (a reference to a double).

      Dim myMthdBuilder As MethodBuilder = myTypeBuilder.DefineMethod("AddFundsFromPool", _
                                MethodAttributes.Public, _
                                GetType(Double), _
                                New Type() {Type.GetType("System.Double&"), _
                                         GetType(Double)})
      
      Dim poolRefBuilder As ParameterBuilder = myMthdBuilder.DefineParameter(1, _
                            ParameterAttributes.Out, "fundsPool")
      
      Dim amountFromPoolBuilder As ParameterBuilder = myMthdBuilder.DefineParameter(2, _
                            ParameterAttributes.In, "amountFromPool")
      
      Dim mthdIL As ILGenerator = myMthdBuilder.GetILGenerator()
      
      mthdIL.Emit(OpCodes.Ldarg_1)
      mthdIL.Emit(OpCodes.Ldarg_1)
      mthdIL.Emit(OpCodes.Ldind_R8)
      mthdIL.Emit(OpCodes.Ldarg_2)
      mthdIL.Emit(OpCodes.Sub)
      
      mthdIL.Emit(OpCodes.Stind_R8)
      
      mthdIL.Emit(OpCodes.Ldarg_0)
      mthdIL.Emit(OpCodes.Ldarg_0)
      mthdIL.Emit(OpCodes.Ldfld, balanceAmtBldr)
      mthdIL.Emit(OpCodes.Ldarg_2)
      mthdIL.Emit(OpCodes.Add)
      
      mthdIL.Emit(OpCodes.Stfld, balanceAmtBldr)
      
      mthdIL.Emit(OpCodes.Ldarg_0)
      mthdIL.Emit(OpCodes.Ldfld, balanceAmtBldr)
      mthdIL.Emit(OpCodes.Ret)
      
      Return myTypeBuilder.CreateType()

   End Function 'BuildCustomerDataType
    
   
   Public Shared Sub Main()

      Dim custType As Type = Nothing
      Dim custObj As Object = Nothing
      
      Dim custArgTypes() As Type = {GetType(String), GetType(String), GetType(Double)}
      
      ' Call the method to build our dynamic class.
      custType = BuildCustomerDataType()
      
      Console.WriteLine("---")
      
      Dim myCustCtor As ConstructorInfo = custType.GetConstructor(custArgTypes)
      Dim initialBalance As Double = 100.0
      custObj = myCustCtor.Invoke(New Object() {"Joe Consumer", "5678-XYZ", initialBalance})
      
      Dim myMemberInfo As MemberInfo() = custType.GetMember("AddFundsFromPool")
      
      
      Dim thePool As Double = 1000.0
      Console.WriteLine("The pool is currently ${0}", thePool)
      Console.WriteLine("The original balance of the account instance is ${0}", initialBalance)
      
      Dim amountFromPool As Double = 50.0
      Console.WriteLine("The amount to be subtracted from the pool and added " & _
            "to the account is ${0}", amountFromPool)
      
      Console.WriteLine("---")
      Console.WriteLine("Calling {0} ...", myMemberInfo(0).ToString())
      Console.WriteLine("---")
      
      Dim passMe() As Object = {thePool, amountFromPool}
      Console.WriteLine("The new balance in the account instance is ${0}", _
                custType.InvokeMember("AddFundsFromPool", _
                BindingFlags.InvokeMethod, Nothing, custObj, passMe))
      thePool = CDbl(passMe(0))
      Console.WriteLine("The new amount in the pool is ${0}", thePool)

   End Sub

End Class

注解

参数属性需要与方法签名一致。如果为参数指定 Out 属性，则应确保该方法参数的类型为类型 ByRef 。

某些 ParameterBuilder 属性要求使用可行的参数调用 DefineMethod ，以便 Microsoft 中间语言 (MSIL) 在运行时正常工作。例如，如果使用 ParameterAttributes.Out 为参数 1 MethodBuilder定义 ParameterBuilder ，则的参数 1 MethodBuilder 必须是一个引用，例如 Type.GetType (“System.String&”) ，而不是 Type.GetType (“System.String”) 。

构造函数

ParameterBuilder()

初始化 ParameterBuilder 类的新实例。

属性

Attributes	检索此参数的属性。
IsIn	检索这是否为输入参数。
IsOptional	检索此参数是否为可选的。
IsOut	检索此参数是否为输出参数。
Name	检索此参数的名称。
Position	检索此参数的签名位置。

方法

Equals(Object)	确定指定对象是否等于当前对象。 (继承自 Object)
GetHashCode()	作为默认哈希函数。 (继承自 Object)
GetToken()	检索此参数的标记。
GetType()	获取当前实例的 Type。 (继承自 Object)
MemberwiseClone()	创建当前 Object 的浅表副本。 (继承自 Object)
SetConstant(Object)	设置该参数的默认值。
SetCustomAttribute(ConstructorInfo, Byte[])	使用指定的自定义属性 blob 设置自定义属性。
SetCustomAttribute(CustomAttributeBuilder)	使用自定义属性生成器设置自定义属性。
SetCustomAttributeCore(ConstructorInfo, ReadOnlySpan<Byte>)	在派生类中重写时，在此程序集上设置自定义属性。
SetMarshal(UnmanagedMarshal)	已过时. 为该参数指定封送处理。
ToString()	返回表示当前对象的字符串。 (继承自 Object)

显式接口实现

_ParameterBuilder.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)	将一组名称映射为对应的一组调度标识符。
_ParameterBuilder.GetTypeInfo(UInt32, UInt32, IntPtr)	检索对象的类型信息，然后可以使用该信息获取接口的类型信息。
_ParameterBuilder.GetTypeInfoCount(UInt32)	检索对象提供的类型信息接口的数量（0 或 1）。
_ParameterBuilder.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)	提供对某一对象公开的属性和方法的访问。

适用于

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