MissingMethodException 类

定义

命名空间:

System

程序集:

netstandard.dll, System.Runtime.dll

Source:

MissingMethodException.cs

尝试动态访问不存在的方法时引发的异常。

public ref class MissingMethodException : MissingMemberException

public class MissingMethodException : MissingMemberException

type MissingMethodException = class
    inherit MissingMemberException

Public Class MissingMethodException
Inherits MissingMemberException

继承

Object

Exception

SystemException

MemberAccessException

MissingMemberException

MissingMethodException

示例

此示例演示了如果尝试使用反射来调用不存在的方法并访问不存在的字段，会发生什么情况。 应用程序通过捕获MissingMethodException和 MissingFieldExceptionMissingMemberException。

using System;
using System.Reflection;

public class App
{
    public static void Main()
    {

        try
        {
            // Attempt to call a static DoSomething method defined in the App class.
            // However, because the App class does not define this method,
            // a MissingMethodException is thrown.
            typeof(App).InvokeMember("DoSomething", BindingFlags.Static |
                BindingFlags.InvokeMethod, null, null, null);
        }
        catch (MissingMethodException e)
        {
            // Show the user that the DoSomething method cannot be called.
            Console.WriteLine("Unable to call the DoSomething method: {0}", e.Message);
        }

        try
        {
            // Attempt to access a static AField field defined in the App class.
            // However, because the App class does not define this field,
            // a MissingFieldException is thrown.
            typeof(App).InvokeMember("AField", BindingFlags.Static | BindingFlags.SetField,
                null, null, new Object[] { 5 });
        }
        catch (MissingFieldException e)
        {
         // Show the user that the AField field cannot be accessed.
         Console.WriteLine("Unable to access the AField field: {0}", e.Message);
        }

        try
        {
            // Attempt to access a static AnotherField field defined in the App class.
            // However, because the App class does not define this field,
            // a MissingFieldException is thrown.
            typeof(App).InvokeMember("AnotherField", BindingFlags.Static |
                BindingFlags.GetField, null, null, null);
        }
        catch (MissingMemberException e)
        {
         // Notice that this code is catching MissingMemberException which is the
         // base class of MissingMethodException and MissingFieldException.
         // Show the user that the AnotherField field cannot be accessed.
         Console.WriteLine("Unable to access the AnotherField field: {0}", e.Message);
        }
    }
}
// This code example produces the following output:
//
// Unable to call the DoSomething method: Method 'App.DoSomething' not found.
// Unable to access the AField field: Field 'App.AField' not found.
// Unable to access the AnotherField field: Field 'App.AnotherField' not found.

open System
open System.Reflection

type App = class end

try
    // Attempt to call a static DoSomething method defined in the App class.
    // However, because the App class does not define this method,
    // a MissingMethodException is thrown.
    typeof<App>.InvokeMember("DoSomething", BindingFlags.Static ||| BindingFlags.InvokeMethod, null, null, null)
    |> ignore
with :? MissingMethodException as e ->
    // Show the user that the DoSomething method cannot be called.
    printfn $"Unable to call the DoSomething method: {e.Message}"

try
    // Attempt to access a static AField field defined in the App class.
    // However, because the App class does not define this field,
    // a MissingFieldException is thrown.
    typeof<App>.InvokeMember("AField", BindingFlags.Static ||| BindingFlags.SetField, null, null, [| box 5 |])
    |> ignore
with :? MissingFieldException as e ->
    // Show the user that the AField field cannot be accessed.
    printfn $"Unable to access the AField field: {e.Message}"

try
    // Attempt to access a static AnotherField field defined in the App class.
    // However, because the App class does not define this field,
    // a MissingFieldException is thrown.
    typeof<App>.InvokeMember("AnotherField", BindingFlags.Static ||| BindingFlags.GetField, null, null, null)
    |> ignore
with :? MissingMemberException as e ->
    // Notice that this code is catching MissingMemberException which is the
    // base class of MissingMethodException and MissingFieldException.
    // Show the user that the AnotherField field cannot be accessed.
    printfn $"Unable to access the AnotherField field: {e.Message}"
// This code example produces the following output:
//     Unable to call the DoSomething method: Method 'App.DoSomething' not found.
//     Unable to access the AField field: Field 'App.AField' not found.
//     Unable to access the AnotherField field: Field 'App.AnotherField' not found.

Imports System.Reflection

Public Class App
    Public Shared Sub Main() 
        Try
            ' Attempt to call a static DoSomething method defined in the App class.
            ' However, because the App class does not define this method, 
            ' a MissingMethodException is thrown.
            GetType(App).InvokeMember("DoSomething", BindingFlags.Static Or BindingFlags.InvokeMethod, _
                                       Nothing, Nothing, Nothing)
        Catch e As MissingMethodException
            ' Show the user that the DoSomething method cannot be called.
            Console.WriteLine("Unable to call the DoSomething method: {0}", e.Message)
        End Try
        Try
            ' Attempt to access a static AField field defined in the App class.
            ' However, because the App class does not define this field, 
            ' a MissingFieldException is thrown.
            GetType(App).InvokeMember("AField", BindingFlags.Static Or BindingFlags.SetField, _
                                       Nothing, Nothing, New [Object]() {5})
        Catch e As MissingFieldException
            ' Show the user that the AField field cannot be accessed.
            Console.WriteLine("Unable to access the AField field: {0}", e.Message)
        End Try
        Try
            ' Attempt to access a static AnotherField field defined in the App class.
            ' However, because the App class does not define this field, 
            ' a MissingFieldException is thrown.
            GetType(App).InvokeMember("AnotherField", BindingFlags.Static Or BindingFlags.GetField, _
                                       Nothing, Nothing, Nothing)
        Catch e As MissingMemberException
            ' Notice that this code is catching MissingMemberException which is the  
            ' base class of MissingMethodException and MissingFieldException.
            ' Show the user that the AnotherField field cannot be accessed.
            Console.WriteLine("Unable to access the AnotherField field: {0}", e.Message)
        End Try
    End Sub 
End Class 
' This code example produces the following output:
'
' Unable to call the DoSomething method: Method 'App.DoSomething' not found.
' Unable to access the AField field: Field 'App.AField' not found.
' Unable to access the AnotherField field: Field 'App.AnotherField' not found.

注解

如果代码尝试访问类不存在的方法，通常会生成编译错误。 MissingMethodException 旨在处理尝试动态访问未由其强名称引用的程序集的已重命名或删除方法的情况。 MissingMethodException 当依赖程序集中的代码尝试访问修改的程序集中缺少的方法时，将引发 。

MissingMethodException 使用具有值0x80131513的 HRESULT COR_E_MISSINGMETHOD。

有关实例 MissingMethodException的初始属性值列表，请参阅 MissingMethodException 构造函数。

未指定加载静态引用方法的确切时间。 在引用缺失方法的方法开始执行之前，可能会引发此异常。

构造函数

名称	说明
MissingMethodException()	初始化 MissingMethodException 类的新实例。
MissingMethodException(SerializationInfo, StreamingContext)	已过时. 使用序列化的数据初始化 MissingMethodException 类的新实例。
MissingMethodException(String, Exception)	使用指定的错误消息和对作为此异常原因的内部异常的引用初始化 MissingMethodException 类的新实例。
MissingMethodException(String, String)	使用指定的类名和方法名称初始化 MissingMethodException 类的新实例。
MissingMethodException(String)	使用指定的错误消息初始化类的新实例 MissingMethodException 。

字段

名称	说明
ClassName	保留缺失成员的类名。 (继承自 MissingMemberException)
MemberName	保留缺失成员的名称。 (继承自 MissingMemberException)
Signature	保存缺失成员的签名。 (继承自 MissingMemberException)

属性

名称	说明
Data	获取键/值对的集合，这些键/值对提供有关异常的其他用户定义的信息。 (继承自 Exception)
HelpLink	获取或设置与此异常关联的帮助文件的链接。 (继承自 Exception)
HResult	获取或设置 HRESULT，它是分配给特定异常的编码数值。 (继承自 Exception)
InnerException	Exception获取导致当前异常的实例。 (继承自 Exception)
Message	获取显示类名、方法名称和缺失方法签名的文本字符串。 此属性为只读。
Source	获取或设置导致错误的应用程序或对象的名称。 (继承自 Exception)
StackTrace	获取调用堆栈上即时帧的字符串表示形式。 (继承自 Exception)
TargetSite	获取引发当前异常的方法。 (继承自 Exception)

方法

名称	说明
Equals(Object)	确定指定对象是否等于当前对象。 (继承自 Object)
GetBaseException()	在派生类中重写时，返回 Exception 一个或多个后续异常的根本原因。 (继承自 Exception)
GetHashCode()	用作默认哈希函数。 (继承自 Object)
GetObjectData(SerializationInfo, StreamingContext)	已过时. SerializationInfo使用类名、成员名称、缺失成员的签名和其他异常信息设置对象。 (继承自 MissingMemberException)
GetType()	获取当前实例的运行时类型。 (继承自 Exception)
MemberwiseClone()	创建当前 Object的浅表副本。 (继承自 Object)
ToString()	创建并返回当前异常的字符串表示形式。 (继承自 Exception)

活动

名称	说明
SerializeObjectState	已过时. 序列化异常以创建包含有关异常的序列化数据的异常状态对象时发生。 (继承自 Exception)

另请参阅

• Exception
• 处理和引发异常