VB.NET InvalidCastException类代码示例

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本文整理汇总了VB.NET中System.InvalidCastException类的典型用法代码示例。如果您正苦于以下问题：VB.NET InvalidCastException类的具体用法？VB.NET InvalidCastException怎么用？VB.NET InvalidCastException使用的例子？那么恭喜您, 这里精选的类代码示例或许可以为您提供帮助。

在下文中一共展示了InvalidCastException类的3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，您的评价将有助于我们的系统推荐出更棒的VB.NET代码示例。

示例1: Example

Module Example
   Public Sub Main()
      Dim flag As Boolean = True
      Try
         Dim conv As IConvertible = flag
         Dim ch As Char = conv.ToChar(Nothing)
         Console.WriteLine("Conversion succeeded.")
      Catch e As InvalidCastException   
         Console.WriteLine("Cannot convert a Boolean to a Char.")
      End Try
      
      Try
         Dim ch As Char = Convert.ToChar(flag)
         Console.WriteLine("Conversion succeeded.")
      Catch e As InvalidCastException   
         Console.WriteLine("Cannot convert a Boolean to a Char.")
      End Try
   End Sub
End Module

开发者ID:VB.NET开发者，项目名称:System，代码行数:19，代码来源:InvalidCastException

输出：

Cannot convert a Boolean to a Char.
Cannot convert a Boolean to a Char.

示例2: Person

Public Class Person
   Dim _name As String
   
   Public Property Name As String
      Get
         Return _name
      End Get
      Set
         _name = value
      End Set
   End Property
End Class

Public Class PersonWithID : Inherits Person
   Dim _id As String
   
   Public Property Id As String
      Get
         Return _id
      End Get
      Set
         _id = value
      End Set
   End Property
End Class

Module Example
   Public Sub Main()
      Dim p As New Person()
      p.Name = "John"
      Try
         Dim pid As PersonWithId = CType(p, PersonWithId)
         Console.WriteLine("Conversion succeeded.")
      Catch e As InvalidCastException
         Console.WriteLine("Conversion failed.")
      End Try 
      
      Dim pid1 As New PersonWithId()
      pid1.Name = "John"
      pid1.Id = "246"
      Dim p1 As Person = pid1
      
      Try   
         Dim pid1a As PersonWithId = CType(p1, PersonWithId)
         Console.WriteLine("Conversion succeeded.")
      Catch e As InvalidCastException
         Console.WriteLine("Conversion failed.")
      End Try 
      
      Dim p2 As Person = Nothing
      Try   
         Dim pid2 As PersonWithId = CType(p2, PersonWithId)
         Console.WriteLine("Conversion succeeded.")
      Catch e As InvalidCastException
         Console.WriteLine("Conversion failed.")
      End Try 
   End Sub
End Module

开发者ID:VB.NET开发者，项目名称:System，代码行数:58，代码来源:InvalidCastException

输出：

Conversion failed.
Conversion succeeded.
Conversion succeeded.

示例3: Main

' 导入命名空间
Imports System.Globalization

Module Example
   Public Sub Main()
      Dim culture As CultureInfo = CultureInfo.InvariantCulture
      Dim provider As IFormatProvider = culture
      
      Dim dt As DateTimeFormatInfo = CType(provider, DateTimeFormatInfo)
   End Sub
End Module

开发者ID:VB.NET开发者，项目名称:System，代码行数:11，代码来源:InvalidCastException

输出：

Unhandled Exception: System.InvalidCastException: 
Unable to cast object of type 'System.Globalization.CultureInfo' to 
type 'System.Globalization.DateTimeFormatInfo'.
at Example.Main()

注：本文中的System.InvalidCastException类示例整理自Github/MSDocs等源码及文档管理平台，相关代码片段筛选自各路编程大神贡献的开源项目，源码版权归原作者所有，传播和使用请参考对应项目的License；未经允许，请勿转载。