String.IsInterned(String) String.IsInterned(String) String.IsInterned(String) String.IsInterned(String) Method

정의

지정된 String에 대한 참조를 검색합니다.Retrieves a reference to a specified String.

public:
 static System::String ^ IsInterned(System::String ^ str);
public static string IsInterned (string str);
static member IsInterned : string -> string
Public Shared Function IsInterned (str As String) As String

매개 변수

str
String String String String

내부 풀에서 검색할 문자열입니다.The string to search for in the intern pool.

반환

str이 공용 언어 런타임 내부 풀에 있으면 해당 참조이고, 그렇지 않으면 null입니다.A reference to str if it is in the common language runtime intern pool; otherwise, null.

예외

예제

다음 예에서는 리터럴 문자열은 컴파일러에 의해 자동으로 인턴 지정 하는 방법을 보여 줍니다.The following example demonstrates that literal strings are interned automatically by the compiler.

// Sample for String::IsInterned(String)
using namespace System;
using namespace System::Text;
using namespace 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)];
void Test( int sequence, String^ str )
{
   Console::Write( "{0} The string '", sequence );
   String^ strInterned = String::IsInterned( str );
   if ( strInterned == nullptr )
      Console::WriteLine( "{0}' is not interned.", str );
   else
      Console::WriteLine( "{0}' is interned.", strInterned );
}

int main()
{
   
   // String str1 is known at compile time, and is automatically interned.
   String^ str1 = "abcd";
   
   // Constructed string, str2, is not explicitly or automatically interned.
   String^ str2 = (gcnew StringBuilder)->Append( "wx" )->Append( "yz" )->ToString();
   Console::WriteLine();
   Test( 1, str1 );
   Test( 2, str2 );
}

//This example produces the following results:

//1) The string, 'abcd', is interned.
//2) The string, 'wxyz', is not interned.

//If you use NGEN.exe to compile the assembly to the native image cache, this
//example produces the following results:

//1) The string, 'abcd', is not interned.
//2) The string, 'wxyz', is not interned.

// Sample for String.IsInterned(String)
using System;
using System.Text;
using 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 static void Main()
    {
        // String str1 is known at compile time, and is automatically interned.
        String str1 = "abcd";

        // Constructed string, str2, is not explicitly or automatically interned.
        String str2 = new StringBuilder().Append("wx").Append("yz").ToString();
        Console.WriteLine();
        Test(1, str1);
        Test(2, str2);
    }

    public static void Test(int sequence, String str)
    {
        Console.Write("{0}) The string, '", sequence);
        String strInterned = String.IsInterned(str);
        if (strInterned == null)
            Console.WriteLine("{0}', is not interned.", str);
        else
            Console.WriteLine("{0}', is interned.", strInterned);
    }
}

//This example produces the following results:

//1) The string, 'abcd', is interned.
//2) The string, 'wxyz', is not interned.

//If you use NGEN.exe to compile the assembly to the native image cache, this
//example produces the following results:

//1) The string, 'abcd', is not interned.
//2) The string, 'wxyz', is not interned.

' 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

'This example produces the following results:

'1) The string, 'abcd', is interned.
'2) The string, 'wxyz', is not interned.

'If you use NGEN.exe to compile the assembly to the native image cache, this
'example produces the following results:

'1) The string, 'abcd', is not interned.
'2) The string, 'wxyz', is not interned.

설명

공용 언어 런타임 내부 풀의 모든 고유한 인스턴스를 비롯 하 여 프로그램에 선언 된 각 고유 리터럴 문자열 상수의 단일 인스턴스를 포함 하는 라는 테이블을를 자동으로 유지 관리 String 호출 하 여 프로그래밍 방식으로 추가 Intern 메서드.The common language runtime automatically maintains a table, called the intern pool, which contains a single instance of each unique literal string constant declared in a program, as well as any unique instance of String you add programmatically by calling the Intern method.

인턴 풀은 문자열 스토리지를 절약합니다.The intern pool conserves string storage. 각 변수를 내부 풀의 여러 인스턴스를 참조 하는 대신 동일한 상수 참조로 여러 변수에 리터럴 문자열 상수를 할당 하는 경우 String 동일한 값을 갖습니다.If you assign a literal string constant to several variables, each variable is set to reference the same constant in the intern pool instead of referencing several different instances of String that have identical values.

이 메서드를 조회 str 내부 풀에 있습니다.This method looks up str in the intern pool. 하는 경우 str 이미이 고, 그렇지 않으면 해당 인스턴스에 대 한 참조는 인턴 지정, null 반환 됩니다.If str has already been interned, a reference to that instance is returned; otherwise, null is returned.

이 메서드를 비교 합니다 Intern 메서드.Compare this method to the Intern method.

이 메서드는 부울 값을 반환 하지 않습니다.This method does not return a Boolean value. 특정 문자열은 인턴 지정 하는지 여부를 나타내는 부울 값 때문에 메서드를 호출 하는 경우에 다음과 같은 코드를 사용할 수 있습니다.If you call the method because you want a Boolean value that indicates whether a particular string is interned, you can use code such as the following.

using System;

public class Example
{
   public static void Main()
   {
      string str1 = "a";
      string str2 = str1 + "b";
      string str3 = str2 + "c";
      string[] strings = { "value", "part1" + "_" + "part2", str3, 
                           String.Empty, null };
      foreach (var value in strings) {
         if (value == null) continue;
         
         bool interned = String.IsInterned(value) != null;
         if (interned)
            Console.WriteLine("'{0}' is in the string intern pool.", 
                              value);
         else
            Console.WriteLine("'{0}' is not in the string intern pool.",
                              value);                      
      }
   }
}
// The example displays the following output:
//       'value' is in the string intern pool.
//       'part1_part2' is in the string intern pool.
//       'abc' is not in the string intern pool.
//       '' is in the string intern pool.
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
' The example displays the following output:
'       'value' is in the string intern pool.
'       'part1_part2' is in the string intern pool.
'       'abc' is not in the string intern pool.
'       '' is in the string intern pool.

참고

.NET Framework 버전 2.0부터 재정의할 수 있습니다 내부 풀 사용 사용 하는 경우는 Ngen.exe (네이티브 이미지 생성기) 로컬 컴퓨터에서 네이티브 이미지 캐시에 어셈블리를 설치 합니다.Starting with the .NET Framework version 2.0, you can override the use of the intern pool when you use the Ngen.exe (Native Image Generator) to install an assembly to the native image cache on a local computer. 자세한 내용은 설명 섹션의 성능 고려 사항을 참조 합니다 Intern 속성입니다.For more information, see Performance Considerations in the Remarks section for the Intern property.

적용 대상

추가 정보