String.ToLower String.ToLower String.ToLower String.ToLower Method

定義

この文字列のコピーを小文字に変換して返します。Returns a copy of this string converted to lowercase.

オーバーロード

ToLower(CultureInfo) ToLower(CultureInfo) ToLower(CultureInfo) ToLower(CultureInfo)

指定されたカルチャの大文字と小文字の規則を使用して、この文字列のコピーを小文字に変換して返します。Returns a copy of this string converted to lowercase, using the casing rules of the specified culture.

ToLower() ToLower() ToLower() ToLower()

この文字列のコピーを小文字に変換して返します。Returns a copy of this string converted to lowercase.

ToLower(CultureInfo) ToLower(CultureInfo) ToLower(CultureInfo) ToLower(CultureInfo)

指定されたカルチャの大文字と小文字の規則を使用して、この文字列のコピーを小文字に変換して返します。Returns a copy of this string converted to lowercase, using the casing rules of the specified culture.

public:
 System::String ^ ToLower(System::Globalization::CultureInfo ^ culture);
public string ToLower (System.Globalization.CultureInfo culture);
member this.ToLower : System.Globalization.CultureInfo -> string
Public Function ToLower (culture As CultureInfo) As String

パラメーター

culture
CultureInfo CultureInfo CultureInfo CultureInfo

カルチャ固有の大文字と小文字の規則を提供するオブジェクト。An object that supplies culture-specific casing rules.

戻り値

現在の文字列を小文字にしたもの。The lowercase equivalent of the current string.

例外

次の例では、2 つの文字列の大文字の文字を英語 (米国)、トルコ語、トルコのカルチャを使用して文字を小文字に変換し、小文字の文字列を比較します。The following example converts two strings of uppercase characters to lowercase characters using the English-United States and Turkish-Turkey cultures, then compares the lowercase strings. 大文字の文字列は、LATIN CAPITAL LETTER I にドットの上、Unicode LATIN CAPITAL LETTER I で 1 つの文字列のうち、その他の文字列に含まれる点を除いて同じです。The uppercase strings are identical except that for each occurrence of the Unicode LATIN CAPITAL LETTER I in one string, the other string contains LATIN CAPITAL LETTER I WITH DOT ABOVE.

// Sample for String::ToLower(CultureInfo)
using namespace System;
using namespace System::Globalization;
void CodePoints( String^ title, String^ s )
{
   Console::Write( "{0}The code points in {1} are: {0}", Environment::NewLine, title );
   System::Collections::IEnumerator^ myEnum = s->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      UInt16 u =  safe_cast<Char>(myEnum->Current);
      Console::Write( "{0:x4} ", u );
   }

   Console::WriteLine();
}

int main()
{
   String^ str1 = "INDIGO";
   
   // str2 = str1, except each 'I' is '\u0130' (Unicode LATIN CAPITAL I WITH DOT ABOVE).
   array<Char>^temp = {L'\u0130',L'N',L'D',L'\u0130',L'G',L'O'};
   String^ str2 = gcnew String( temp );
   String^ str3;
   String^ str4;
   Console::WriteLine();
   Console::WriteLine( "str1 = '{0}'", str1 );
   Console::WriteLine();
   Console::WriteLine( "str1 is {0} to str2.", ((0 == String::CompareOrdinal( str1, str2 )) ? (String^)"equal" : "not equal") );
   CodePoints( "str1", str1 );
   CodePoints( "str2", str2 );
   Console::WriteLine();
   
   // str3 is a lower case copy of str2, using English-United States culture.
   Console::WriteLine( "str3 = Lower case copy of str2 using English-United States culture." );
   str3 = str2->ToLower( gcnew CultureInfo( "en-US",false ) );
   
   // str4 is a lower case copy of str2, using Turkish-Turkey culture.
   Console::WriteLine( "str4 = Lower case copy of str2 using Turkish-Turkey culture." );
   str4 = str2->ToLower( gcnew CultureInfo( "tr-TR",false ) );
   
   // Compare the code points in str3 and str4.
   Console::WriteLine();
   Console::WriteLine( "str3 is {0} to str4.", ((0 == String::CompareOrdinal( str3, str4 )) ? (String^)"equal" : "not equal") );
   CodePoints( "str3", str3 );
   CodePoints( "str4", str4 );
}

/*
This example produces the following results:

str1 = 'INDIGO'

str1 is not equal to str2.

The code points in str1 are:
0049 004e 0044 0049 0047 004f

The code points in str2 are:
0130 004e 0044 0130 0047 004f

str3 = Lower case copy of str2 using English-United States culture.
str4 = Lower case copy of str2 using Turkish-Turkey culture.

str3 is equal to str4.

The code points in str3 are:
0069 006e 0064 0069 0067 006f

The code points in str4 are:
0069 006e 0064 0069 0067 006f
*/
// Sample for String.ToLower(CultureInfo)

using System;
using System.Globalization;

class Sample 
{
    public static void Main() 
    {
    String str1 = "INDIGO";
    // str2 = str1, except each 'I' is '\u0130' (Unicode LATIN CAPITAL I WITH DOT ABOVE).
    String str2 = new String(new Char[] {'\u0130', 'N', 'D', '\u0130', 'G', 'O'});
    String str3, str4;

    Console.WriteLine();
    Console.WriteLine("str1 = '{0}'", str1);

    Console.WriteLine();
    Console.WriteLine("str1 is {0} to str2.", 
         ((0 == String.CompareOrdinal(str1, str2)) ? "equal" : "not equal"));
    CodePoints("str1", str1);
    CodePoints("str2", str2);

    Console.WriteLine();
    // str3 is a lower case copy of str2, using English-United States culture.
    Console.WriteLine("str3 = Lower case copy of str2 using English-United States culture.");
    str3 = str2.ToLower(new CultureInfo("en-US", false));

    // str4 is a lower case copy of str2, using Turkish-Turkey culture.
    Console.WriteLine("str4 = Lower case copy of str2 using Turkish-Turkey culture.");
    str4 = str2.ToLower(new CultureInfo("tr-TR", false));

    // Compare the code points in str3 and str4.
    Console.WriteLine();
    Console.WriteLine("str3 is {0} to str4.", 
         ((0 == String.CompareOrdinal(str3, str4)) ? "equal" : "not equal"));
    CodePoints("str3", str3);
    CodePoints("str4", str4);
    }

    public static void CodePoints(String title, String s)
    {
    Console.Write("{0}The code points in {1} are: {0}", Environment.NewLine, title);
    foreach (ushort u in s)
      Console.Write("{0:x4} ", u);
    Console.WriteLine();
    }
}
/*
This example produces the following results:

str1 = 'INDIGO'

str1 is not equal to str2.

The code points in str1 are:
0049 004e 0044 0049 0047 004f

The code points in str2 are:
0130 004e 0044 0130 0047 004f

str3 = Lower case copy of str2 using English-United States culture.
str4 = Lower case copy of str2 using Turkish-Turkey culture.

str3 is equal to str4.

The code points in str3 are:
0069 006e 0064 0069 0067 006f

The code points in str4 are:
0069 006e 0064 0069 0067 006f
*/
' Sample for String.ToLower(CultureInfo)
Imports System
Imports System.Globalization
Imports Microsoft.VisualBasic

Class Sample
   Public Shared Sub Main()
      Dim str1 As [String] = "INDIGO"
      ' str2 = str1, except each 'I' is '\u0130' (Unicode LATIN CAPITAL I WITH DOT ABOVE).
      Dim str2 As New [String](New [Char]() {ChrW(&H0130), "N"c, "D"c, ChrW(&H0130), "G"c, "O"c})
      Dim str3, str4 As [String]

      Console.WriteLine()
      Console.WriteLine("str1 = '{0}'", str1)

      Console.WriteLine()
      Console.WriteLine("str1 is {0} to str2.", _
                         IIf(0 = [String].CompareOrdinal(str1, str2), "equal", "not equal"))
      CodePoints("str1", str1)
      CodePoints("str2", str2)

      Console.WriteLine()
      ' str3 is a lower case copy of str2, using English-United States culture.
      Console.WriteLine("str3 = Lower case copy of str2 using English-United States culture.")
      str3 = str2.ToLower(New CultureInfo("en-US", False))

      ' str4 is a lower case copy of str2, using Turkish-Turkey culture.
      Console.WriteLine("str4 = Lower case copy of str2 using Turkish-Turkey culture.")
      str4 = str2.ToLower(New CultureInfo("tr-TR", False))

      ' Compare the code points in str3 and str4.
      Console.WriteLine()
      Console.WriteLine("str3 is {0} to str4.", _
                         IIf(0 = [String].CompareOrdinal(str3, str4), "equal", "not equal"))
      CodePoints("str3", str3)
      CodePoints("str4", str4)
   End Sub 'Main

   Public Shared Sub CodePoints(title As [String], s As [String])
      Console.Write("{0}The code points in {1} are: {0}", Environment.NewLine, title)
      Dim c As Char
      For Each c In  s
         Console.Write("{0:x4} ", AscW(c))
      Next c
      Console.WriteLine()
   End Sub 'CodePoints
End Class 'Sample
'
'str1 = 'INDIGO'
'
'str1 is not equal to str2.
'
'The code points in str1 are:
'0049 004e 0044 0049 0047 004f
'
'The code points in str2 are:
'0130 004e 0044 0130 0047 004f
'
'str3 = Lower case copy of str2 using English-United States culture.
'str4 = Lower case copy of str2 using Turkish-Turkey culture.
'
'str3 is equal to str4.
'
'The code points in str3 are:
'0069 006e 0064 0069 0067 006f
'
'The code points in str4 are:
'0069 006e 0064 0069 0067 006f

注釈

指定されたカルチャの大文字小文字の規則、cultureパラメーターを変更する方法、文字列の大文字と小文字を決定します。The casing rules of the culture specified by the culture parameter determine the way the case of the string is changed.

注意

このメソッドは、現在のインスタンスの値を変更できません。This method does not modify the value of the current instance. 代わりに、現在のインスタンス内のすべての文字が小文字に変換する新しい文字列を返します。Instead, it returns a new string in which all characters in the current instance are converted to lowercase.

セキュリティの考慮事項Security Considerations

渡す場合、ToLower(CultureInfo)メソッド、CultureInfoオブジェクト以外のCultureInfo.InvariantCulture、大文字と小文字の操作がカルチャに固有のルールが考慮します。If you pass the ToLower(CultureInfo) method a CultureInfo object other than CultureInfo.InvariantCulture, the casing operation will take culture-specific rules into account. 名前付きパイプ、またはレジストリ キーの使用をファイル名など、オペレーティング システムの識別子の大文字か小文字のバージョンが必要な場合、ToLowerInvariantまたはToUpperInvariantメソッド。If you need the lowercase or uppercase version of an operating system identifier, such as a file name, named pipe, or registry key, use the ToLowerInvariant or ToUpperInvariant method. これにより、すべてのカルチャで同じ結果になりより効率的に実行します。This produces the same result in every culture and performs more efficiently.

こちらもご覧ください

ToLower() ToLower() ToLower() ToLower()

この文字列のコピーを小文字に変換して返します。Returns a copy of this string converted to lowercase.

public:
 System::String ^ ToLower();
public string ToLower ();
member this.ToLower : unit -> string
Public Function ToLower () As String

戻り値

小文字の文字列。A string in lowercase.

次の例では、いくつかの混合大文字と小文字の文字列を小文字に変換します。The following example converts several mixed case strings to lowercase.

using namespace System;
using namespace System::Collections;
int main()
{
   array<String^>^info = {"Name","Title","Age","Location","Gender"};
   Console::WriteLine( "The initial values in the array are:" );
   IEnumerator^ myEnum = info->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      String^ s = safe_cast<String^>(myEnum->Current);
      Console::WriteLine( s );
   }

   Console::WriteLine( " {0}The lowercase of these values is:", Environment::NewLine );
   IEnumerator^ myEnum1 = info->GetEnumerator();
   while ( myEnum1->MoveNext() )
   {
      String^ s = safe_cast<String^>(myEnum1->Current);
      Console::WriteLine( s->ToLower() );
   }

   Console::WriteLine( " {0}The uppercase of these values is:", Environment::NewLine );
   IEnumerator^ myEnum2 = info->GetEnumerator();
   while ( myEnum2->MoveNext() )
   {
      String^ s = safe_cast<String^>(myEnum2->Current);
      Console::WriteLine( s->ToUpper() );
   }
}
// The example displays the following output:
//       The initial values in the array are:
//       Name
//       Title
//       Age
//       Location
//       Gender
//       
//       The lowercase of these values is:
//       name
//       title
//       age
//       location
//       gender
//       
//       The uppercase of these values is:
//       NAME
//       TITLE
//       AGE
//       LOCATION
//       GENDER
using System;

public class ToLowerTest {
    public static void Main() {

        string [] info = {"Name", "Title", "Age", "Location", "Gender"};

        Console.WriteLine("The initial values in the array are:");
        foreach (string s in info)
            Console.WriteLine(s);

        Console.WriteLine("{0}The lowercase of these values is:", Environment.NewLine);        

        foreach (string s in info)
            Console.WriteLine(s.ToLower());

        Console.WriteLine("{0}The uppercase of these values is:", Environment.NewLine);        

        foreach (string s in info)
            Console.WriteLine(s.ToUpper());
    }
}
// The example displays the following output:
//       The initial values in the array are:
//       Name
//       Title
//       Age
//       Location
//       Gender
//       
//       The lowercase of these values is:
//       name
//       title
//       age
//       location
//       gender
//       
//       The uppercase of these values is:
//       NAME
//       TITLE
//       AGE
//       LOCATION
//       GENDER
Imports System

Public Class ToLowerTest
    
    Public Shared Sub Main()
        Dim info As String() = {"Name", "Title", "Age", "Location", "Gender"}
        
        Console.WriteLine("The initial values in the array are:")

        Dim s As String
        For Each s In info
            Console.WriteLine(s)
        Next 

        Console.WriteLine("{0}The lowercase of these values is:", Environment.NewLine)

        For Each s In info
            Console.WriteLine(s.ToLower())
        Next 

        Console.WriteLine("{0}The uppercase of these values is:", Environment.NewLine)

        For Each s In  info
            Console.WriteLine(s.ToUpper())
        Next 
    End Sub 
End Class 
' The example displays the following output:
'       The initial values in the array are:
'       Name
'       Title
'       Age
'       Location
'       Gender
'       
'       The lowercase of these values is:
'       name
'       title
'       age
'       location
'       gender
'       
'       The uppercase of these values is:
'       NAME
'       TITLE
'       AGE
'       LOCATION
'       GENDER

注釈

このメソッドでは、現在のカルチャの大文字小文字の規則が考慮されます。This method takes into account the casing rules of the current culture.

注意

このメソッドは、現在のインスタンスの値を変更できません。This method does not modify the value of the current instance. 代わりに、現在のインスタンス内のすべての文字が小文字に変換する新しい文字列を返します。Instead, it returns a new string in which all characters in the current instance are converted to lowercase.

セキュリティの考慮事項Security Considerations

大文字と小文字の操作呼び出しに起因する、ToLower()メソッドは、現在のカルチャのケース表記規則が考慮されます。The casing operation that results from calling the ToLower() method takes the casing conventions of the current culture into account. 名前付きパイプ、またはレジストリ キーの使用をファイル名など、オペレーティング システムの識別子の大文字か小文字のバージョンが必要な場合、ToLowerInvariantまたはToUpperInvariantメソッド。If you need the lowercase or uppercase version of an operating system identifier, such as a file name, named pipe, or registry key, use the ToLowerInvariant or ToUpperInvariant methods. すべてのカルチャで同じ結果が生成されます (とは異なり、ToLower()メソッド) より効率的に実行します。This produces the same result in every culture (unlike the ToLower() method) and performs more efficiently.

注意 (呼び出し元)

説明したよう文字列を使用するためのベスト プラクティス既定値を代入しを明示的に指定するパラメーターを必要とするメソッドを呼び出す代わりに文字列の大文字小文字の区別メソッドを呼び出さないようにすることをお勧めします。As explained in Best Practices for Using Strings, we recommend that you avoid calling string casing methods that substitute default values and instead call methods that require parameters to be explicitly specified. 現在のカルチャの大文字と小文字の規則を使用して小文字の文字を変換するを呼び出して、ToLower(CultureInfo)メソッドのオーバー ロードの値を持つCurrentCulturecultureパラメーター。To convert a character to lowercase by using the casing conventions of the current culture, call the ToLower(CultureInfo) method overload with a value of CurrentCulture for its culture parameter.

こちらもご覧ください

適用対象