vb System.AppContext类(方法)实例源码

' 导入命名空间
Imports System.Reflection

<Assembly: AssemblyVersion("1.0.0.0")>

Public Class StringLibrary
   Public Shared Function SubstringStartsAt(fullString As String, substr As String) As Integer
      Return fullString.IndexOf(substr, StringComparison.Ordinal)
   End Function
End Class

Public Module Example
   Public Sub Main()
      Dim value As String = "The archaeologist"
      Dim substring As String = "archæ"
      Dim position As Integer = StringLibrary.SubstringStartsAt(value, substring) 
      If position >= 0 Then 
         Console.WriteLine("'{0}' found in '{1}' starting at position {2}",
                        substring, value, position)
      Else
         Console.WriteLine("'{0}' not found in '{1}'", substring, value)
      End If                  
   End Sub
End Module

' 导入命名空间
Imports System.Reflection

<Assembly: AssemblyVersion("2.0.0.0")>

Public Class StringLibrary
   Public Shared Function SubstringStartsAt(fullString As String, substr As String) As Integer
      Return fullString.IndexOf(substr, StringComparison.CurrentCulture)
   End Function
End Class

' 导入命名空间
Imports System.Reflection

<Assembly: AssemblyVersion("2.0.0.0")>

Public Class StringLibrary
   Public Shared Function SubstringStartsAt(fullString As String, substr As String) As Integer
      Dim flag As Boolean
      If AppContext.TryGetSwitch("StringLibrary.DoNotUseCultureSensitiveComparison", flag) AndAlso flag = True Then
         Return fullString.IndexOf(substr, StringComparison.Ordinal)
      Else
         Return fullString.IndexOf(substr, StringComparison.CurrentCulture)
      End If   
   End Function
End Class

' 导入命名空间
Imports System.IO
Imports System.Runtime.Versioning

<assembly:TargetFramework(".NETFramework,Version=v4.6.2")>

Module Example
   Public Sub Main()
      Console.WriteLine(Path.GetDirectoryName("file://c/temp/dirlist.txt")) 
   End Sub
End Module