vb System.String.IsInterned类(方法)实例源码

' Sample for String.IsInterned(String)
Imports System.Text
Imports System.Runtime.CompilerServices

' In the .NET Framework 2.0 the following attribute declaration allows you to 
' avoid the use of the interning when you use NGEN.exe to compile an assembly 
' to the native image cache.
<Assembly: CompilationRelaxations(CompilationRelaxations.NoStringInterning)> 
Class Sample
    Public Shared Sub Main()
        ' String str1 is known at compile time, and is automatically interned.
        Dim str1 As [String] = "abcd"

        ' Constructed string, str2, is not explicitly or automatically interned.
        Dim str2 As [String] = New StringBuilder().Append("wx").Append("yz").ToString()
        Console.WriteLine()
        Test(1, str1)
        Test(2, str2)
    End Sub

    Public Shared Sub Test(ByVal sequence As Integer, ByVal str As [String])
        Console.Write("{0}) The string, '", sequence)
        Dim strInterned As [String] = [String].IsInterned(str)
        If strInterned Is Nothing Then
            Console.WriteLine("{0}', is not interned.", str)
        Else
            Console.WriteLine("{0}', is interned.", strInterned)
        End If
    End Sub
End Class

Module Example
   Public Sub Main()
      Dim str1 As String = "a"
      Dim str2 As String = str1 + "b"
      Dim str3 As String = str2 + "c"
      Dim strings() As String = { "value", "part1" + "_" + "part2", str3, 
                                  String.Empty, Nothing }
      For Each value In strings
         If value Is Nothing Then Continue For
         
         Dim interned As Boolean = (String.IsInterned(value) IsNot Nothing)
         If interned Then
            Console.WriteLine("'{0}' is in the string intern pool.", 
                              value)
         Else
            Console.WriteLine("'{0}' is not in the string intern pool.",
                              value)                      
         End If
      Next
   End Sub
End Module