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VB.NET Type.InvokeMember方法代码示例

本文整理汇总了VB.NET中System.Type.InvokeMember方法的典型用法代码示例。如果您正苦于以下问题:VB.NET Type.InvokeMember方法的具体用法?VB.NET Type.InvokeMember怎么用?VB.NET Type.InvokeMember使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在System.Type的用法示例。


在下文中一共展示了Type.InvokeMember方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的VB.NET代码示例。

示例1: MyType

' 导入命名空间
Imports System.Reflection

' This sample class has a field, constructor, method, and property.
Class MyType
    Private myField As Int32

    Public Sub New(ByRef x As Int32)
        x *= 5
    End Sub

    Public Overrides Function ToString() As [String]
        Return myField.ToString()
    End Function 'ToString

    Public Property MyProp() As Int32
        Get
            Return myField
        End Get
        Set(ByVal Value As Int32)
            If Value < 1 Then
                Throw New ArgumentOutOfRangeException("value", Value, "value must be > 0")
            End If
            myField = Value
        End Set
    End Property
End Class

Class MyApp

    Shared Sub Main()
        Dim t As Type = GetType(MyType)
        ' Create an instance of a type.
        Dim args() As [Object] = {8}
        Console.WriteLine("The value of x before the constructor is called is {0}.", args(0))
        Dim obj As [Object] = t.InvokeMember(Nothing, BindingFlags.DeclaredOnly Or BindingFlags.Public Or BindingFlags.NonPublic Or BindingFlags.Instance Or BindingFlags.CreateInstance, Nothing, Nothing, args)
        Console.WriteLine("Type: {0}", obj.GetType().ToString())
        Console.WriteLine("The value of x after the constructor returns is {0}.", args(0))

        ' Read and write to a field.
        t.InvokeMember("myField", BindingFlags.DeclaredOnly Or BindingFlags.Public Or BindingFlags.NonPublic Or BindingFlags.Instance Or BindingFlags.SetField, Nothing, obj, New [Object]() {5})
        Dim v As Int32 = CType(t.InvokeMember("myField", BindingFlags.DeclaredOnly Or BindingFlags.Public Or BindingFlags.NonPublic Or BindingFlags.Instance Or BindingFlags.GetField, Nothing, obj, Nothing), Int32)
        Console.WriteLine("myField: {0}", v)

        ' Call a method.
        Dim s As [String] = CType(t.InvokeMember("ToString", BindingFlags.DeclaredOnly Or BindingFlags.Public Or BindingFlags.NonPublic Or BindingFlags.Instance Or BindingFlags.InvokeMethod, Nothing, obj, Nothing), [String])
        Console.WriteLine("ToString: {0}", s)

        ' Read and write a property. First, attempt to assign an
        ' invalid value; then assign a valid value; finally, get
        ' the value.
        Try
            ' Assign the value zero to MyProp. The Property Set 
            ' throws an exception, because zero is an invalid value.
            ' InvokeMember catches the exception, and throws 
            ' TargetInvocationException. To discover the real cause
            ' you must catch TargetInvocationException and examine
            ' the inner exception. 
            t.InvokeMember("MyProp", BindingFlags.DeclaredOnly Or BindingFlags.Public Or BindingFlags.NonPublic Or BindingFlags.Instance Or BindingFlags.SetProperty, Nothing, obj, New [Object]() {0})
        Catch e As TargetInvocationException
            ' If the property assignment failed for some unexpected
            ' reason, rethrow the TargetInvocationException.
            If Not e.InnerException.GetType() Is GetType(ArgumentOutOfRangeException) Then
                Throw
            End If
            Console.WriteLine("An invalid value was assigned to MyProp.")
        End Try
        t.InvokeMember("MyProp", BindingFlags.DeclaredOnly Or BindingFlags.Public Or BindingFlags.NonPublic Or BindingFlags.Instance Or BindingFlags.SetProperty, Nothing, obj, New [Object]() {2})
        v = CType(t.InvokeMember("MyProp", BindingFlags.DeclaredOnly Or BindingFlags.Public Or BindingFlags.NonPublic Or BindingFlags.Instance Or BindingFlags.GetProperty, Nothing, obj, Nothing), Int32)
        Console.WriteLine("MyProp: {0}", v)
    End Sub
End Class
开发者ID:VB.NET开发者,项目名称:System,代码行数:72,代码来源:Type.InvokeMember


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