ParameterInfo.IsIn プロパティ

public:
 property bool IsIn { bool get(); };

public bool IsIn { get; }

member this.IsIn : bool

Public ReadOnly Property IsIn As Boolean

プロパティ値

true パラメーターが入力パラメーターの場合。それ以外の場合は false。

例

次の例は、 ParameterAttributes.In、 ParameterAttributes.Out、および ParameterAttributes.Optional 属性のメソッド パラメーターをテストする方法を示しています。

この例には、次の DefineMethod メソッドが含まれています。

• MyType型を含む動的アセンブリを作成します。

• MyMethod メソッドをMyTypeに追加します。 MyMethod には 3 つのパラメーターがあります。 最初のパラメーターは、 ParameterAttributes.In、2 番目のパラメーターは ParameterAttributes.Out、3 番目のパラメーターは ParameterAttributes.Optional で定義されます。

• TypeBuilder.CreateTypeを呼び出して型を完了します。

DefineMethodを実行した後、動的アセンブリが見つかるまで、現在読み込まれているアセンブリを検索します。 アセンブリからMyTypeを読み込み、MyMethod メソッドのMethodInfo オブジェクトを取得し、パラメーターを調べます。 この例では、 IsIn、 IsOut、および IsOptional プロパティを使用して、パラメーターに関する情報を表示します。

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

public class ParameterInfo_IsIn_IsOut_IsOptional
{
   public static void DefineMethod()
   {
      AssemblyName myAssemblyName = new AssemblyName();
      myAssemblyName.Name = "MyAssembly";
      // Get the assembly builder from the application domain associated with the current thread.
      AssemblyBuilder myAssemblyBuilder = Thread.GetDomain().DefineDynamicAssembly(myAssemblyName, AssemblyBuilderAccess.RunAndSave);
      // Create a dynamic module in the assembly.
      ModuleBuilder myModuleBuilder = myAssemblyBuilder.DefineDynamicModule("MyModule", "MyAssembly.dll");
      // Create a type in the module.
      TypeBuilder myTypeBuilder = myModuleBuilder.DefineType("MyType");
      // Create a method called MyMethod.
      MethodBuilder myMethodBuilder = myTypeBuilder.DefineMethod("MyMethod",MethodAttributes.Public | MethodAttributes.HideBySig |
                                                                           MethodAttributes.Static, typeof(string), new Type[] {typeof(int), typeof(short), typeof(long)});
      // Set the attributes for the parameters of the method.
      // Set the attribute for the first parameter to IN.
      ParameterBuilder myParameterBuilder = myMethodBuilder.DefineParameter(1, ParameterAttributes.In, "MyIntParameter");
      // Set the attribute for the second parameter to OUT.
      myParameterBuilder = myMethodBuilder.DefineParameter(2, ParameterAttributes.Out, "MyShortParameter");
      // Set the attribute for the third parameter to OPTIONAL.
      myParameterBuilder = myMethodBuilder.DefineParameter(3, ParameterAttributes.Optional | ParameterAttributes.HasDefault, "MyLongParameter");
      // Get the Microsoft Intermediate Language generator for the method.
      ILGenerator myILGenerator = myMethodBuilder.GetILGenerator();
      // Use the utility method to generate the MSIL instructions that print a string to the console.
      myILGenerator.EmitWriteLine("Hello World!");
      // Generate the "ret" MSIL instruction.
      myILGenerator.Emit(OpCodes.Ret);
      // End the creation of the type.
      myTypeBuilder.CreateType();
   }

   public static void Main()
   {
      // Create a dynamic assembly with a type named MyType.
      DefineMethod();

      // Get the assemblies currently loaded in the application domain.
      Assembly[] myAssemblies = Thread.GetDomain().GetAssemblies();
      Assembly myAssembly = null;
      // Get the assembly named MyAssembly.
      for(int i = 0; i < myAssemblies.Length; i++)
         if(String.Compare(myAssemblies[i].GetName(false).Name, "MyAssembly") == 0)
            myAssembly = myAssemblies[i];

      if(myAssembly != null)
      {
         // Get a type named MyType.
         Type myType = myAssembly.GetType("MyType");
         // Get a method named MyMethod from the type.
         MethodBase myMethodBase = myType.GetMethod("MyMethod");
         // Get the parameters associated with the method.
         ParameterInfo[] myParameters = myMethodBase.GetParameters();
         Console.WriteLine("\nThe method {0} has the {1} parameters :",
            myMethodBase, myParameters.Length);
         // Print the IN, OUT and OPTIONAL attributes associated with each of the parameters.
         for(int i = 0; i < myParameters.Length; i++)
         {
            if(myParameters[i].IsIn)
               Console.WriteLine("\tThe {0} parameter has the In attribute",
                                       i + 1);
            if(myParameters[i].IsOptional)
               Console.WriteLine("\tThe {0} parameter has the Optional attribute",
                                       i + 1);
            if(myParameters[i].IsOut)
               Console.WriteLine("\tThe {0} parameter has the Out attribute",
                                       i + 1);
         }
      }
      else
        {
            Console.WriteLine("Could not find a assembly named 'MyAssembly' for the current application domain");
        }
    }
}

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

Public Class ParameterInfo_IsIn_IsOut_IsOptional
   
   Public Shared Sub DefineMethod()
      Dim myAssemblyName As New AssemblyName()
      myAssemblyName.Name = "MyAssembly"
      ' Get the assesmbly builder from the application domain associated with the current thread.
      Dim myAssemblyBuilder As AssemblyBuilder = Thread.GetDomain().DefineDynamicAssembly(myAssemblyName, AssemblyBuilderAccess.RunAndSave)
      ' Create a dynamic module in the assembly.
      Dim myModuleBuilder As ModuleBuilder = myAssemblyBuilder.DefineDynamicModule("MyModule", "MyAssembly.dll")
      ' Create a type in the module.
      Dim myTypeBuilder As TypeBuilder = myModuleBuilder.DefineType("MyType")
      ' Create a method called MyMethod.
      Dim myMethodBuilder As MethodBuilder = myTypeBuilder.DefineMethod("MyMethod", MethodAttributes.Public Or MethodAttributes.HideBySig Or MethodAttributes.Static, GetType(String), New Type() {GetType(Integer), GetType(Short), GetType(Long)})
      ' Set the attributes for the parameters of the method.
      ' Set the attribute for the first parameter to IN.
      Dim myParameterBuilder As ParameterBuilder = myMethodBuilder.DefineParameter(1, ParameterAttributes.In, "MyIntParameter")
      ' Set the attribute for the second parameter to OUT.
      myParameterBuilder = myMethodBuilder.DefineParameter(2, ParameterAttributes.Out, "MyShortParameter")
      ' Set the attribute for the third parameter to OPTIONAL.
      myParameterBuilder = myMethodBuilder.DefineParameter(3, ParameterAttributes.Optional Or ParameterAttributes.HasDefault, "MyLongParameter")
      ' Get the Microsoft Intermediate Language generator for the method.
      Dim myILGenerator As ILGenerator = myMethodBuilder.GetILGenerator()
      ' Use the utility method to generate the MSIL instructions that print a string to the console.
      myILGenerator.EmitWriteLine("Hello World!")
      ' Generate the "ret" MSIL instruction.
      myILGenerator.Emit(OpCodes.Ret)
      ' End the creation of the type.
      myTypeBuilder.CreateType()
   End Sub
   
   
   Public Shared Sub Main()
      ' Create a dynamic assembly with a type named 'MyType'.
      DefineMethod()
      
      ' Get the assemblies currently loaded in the application domain.
      Dim myAssemblies As [Assembly]() = Thread.GetDomain().GetAssemblies()
      Dim myAssembly As [Assembly] = Nothing
      ' Get the assembly named MyAssembly.
      Dim i As Integer
      For i = 0 To myAssemblies.Length - 1
         If [String].Compare(myAssemblies(i).GetName(False).Name, "MyAssembly") = 0 Then
            myAssembly = myAssemblies(i)
         End If 
      Next i
      If Not (myAssembly Is Nothing) Then
         ' Get a type named MyType.
         Dim myType As Type = myAssembly.GetType("MyType")
         ' Get a method named MyMethod from the type.
         Dim myMethodBase As MethodBase = myType.GetMethod("MyMethod")
         ' Get the parameters associated with the method.
         Dim myParameters As ParameterInfo() = myMethodBase.GetParameters()
         Console.WriteLine(ControlChars.Cr + "The method {0} has the {1} parameters :", myMethodBase, myParameters.Length)
         ' Print the IN, OUT and OPTIONAL attributes associated with each of the parameters.
         For i = 0 To myParameters.Length - 1
            If myParameters(i).IsIn Then
               Console.WriteLine(ControlChars.Tab + "The {0} parameter has the In attribute", i + 1)
            End If
            If myParameters(i).IsOptional Then
               Console.WriteLine(ControlChars.Tab + "The {0} parameter has the Optional attribute", i + 1)
            End If
            If myParameters(i).IsOut Then
               Console.WriteLine(ControlChars.Tab + "The {0} parameter has the Out attribute", i + 1)
            End If
         Next i
      Else
         Console.WriteLine("Could not find a assembly named 'MyAssembly' for the current application domain")
      End If
   End Sub
End Class

注釈

このメソッドは、省略可能なメタデータ フラグに依存します。 このフラグはコンパイラによって挿入できますが、コンパイラでは挿入する必要はありません。

このメソッドは、ParameterAttributes列挙子のIn フラグを使用します。

ParameterInfo配列を取得するには、まずメソッドまたはコンストラクターを取得してから、MethodBase.GetParametersを呼び出します。