String.Equals String.Equals String.Equals String.Equals Method

定義

2 つの String オブジェクトの値が同一かどうかを判断します。Determines whether two String objects have the same value.

オーバーロード

Equals(String, StringComparison) Equals(String, StringComparison) Equals(String, StringComparison) Equals(String, StringComparison)

この文字列と、指定した String オブジェクトの値が同一かどうかを判断します。Determines whether this string and a specified String object have the same value. 比較に使用するカルチャ、大文字と小文字の区別、および、並べ替え規則をパラメーターで指定します。A parameter specifies the culture, case, and sort rules used in the comparison.

Equals(String, String) Equals(String, String) Equals(String, String) Equals(String, String)

指定した 2 つの String オブジェクトの値が同一かどうかを判断します。Determines whether two specified String objects have the same value.

Equals(String, String, StringComparison) Equals(String, String, StringComparison) Equals(String, String, StringComparison) Equals(String, String, StringComparison)

指定した 2 つの String オブジェクトの値が同一かどうかを判断します。Determines whether two specified String objects have the same value. 比較に使用するカルチャ、大文字と小文字の区別、および、並べ替え規則をパラメーターで指定します。A parameter specifies the culture, case, and sort rules used in the comparison.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

このインスタンスと、指定したオブジェクトの値が同一かどうかを判断します。String オブジェクトを指定する必要があります。Determines whether this instance and a specified object, which must also be a String object, have the same value.

Equals(String) Equals(String) Equals(String) Equals(String)

このインスタンスと、指定した別の String の値が同一かどうかを判断します。Determines whether this instance and another specified String object have the same value.

Equals(String, StringComparison) Equals(String, StringComparison) Equals(String, StringComparison) Equals(String, StringComparison)

この文字列と、指定した String オブジェクトの値が同一かどうかを判断します。Determines whether this string and a specified String object have the same value. 比較に使用するカルチャ、大文字と小文字の区別、および、並べ替え規則をパラメーターで指定します。A parameter specifies the culture, case, and sort rules used in the comparison.

public:
 bool Equals(System::String ^ value, StringComparison comparisonType);
public bool Equals (string value, StringComparison comparisonType);
override this.Equals : string * StringComparison -> bool
Public Function Equals (value As String, comparisonType As StringComparison) As Boolean

パラメーター

value
String String String String

このインスタンスと比較する文字列。The string to compare to this instance.

comparisonType
StringComparison StringComparison StringComparison StringComparison

文字列の比較方法を指定する列挙値の 1 つ。One of the enumeration values that specifies how the strings will be compared.

戻り値

true パラメーターの値がこの文字列と同じ場合は value。それ以外の場合は falsetrue if the value of the value parameter is the same as this string; otherwise, false.

例外

comparisonTypeStringComparison 値ではありません。comparisonType is not a StringComparison value.

次の例では、"I"、"i"小文字およびドットなしの「ı」の大文字で構成される文字列配列を作成します。The following example creates a string array that consists of an uppercase "I", a lowercase "i", and a dotless "ı". 呼び出して、Equals(String, StringComparison)可能性のある各を使用して比較するためのメソッドStringComparison列挙値。It then calls the Equals(String, StringComparison) method to compare them by using each possible StringComparison enumeration value.

using System;

class Sample 
{
   public static void Main() 
   {
      // Define a string array with the following three "I" characters:
      //      U+0069, U+0131, and U+0049.  
      string[] threeIs = { "i", "ı", "I" };
      // Define Type object representing StringComparison type.
      Type scType = typeof(StringComparison);  
      
      // Show the current culture (for culture-sensitive string comparisons).
      Console.WriteLine("The current culture is {0}.\n", 
                        System.Globalization.CultureInfo.CurrentCulture.Name);
        
      // Perform comparisons using each StringComparison member. 
      foreach (string scName in Enum.GetNames(scType))
      {
         StringComparison sc = (StringComparison) Enum.Parse(scType, scName);
         Console.WriteLine("Comparisons using {0}:", sc);
         // Compare each character in character array.
         for (int ctr = 0; ctr <= 1; ctr++)
         {
            string instanceChar = threeIs[ctr];
            for (int innerCtr = ctr + 1; innerCtr <= threeIs.GetUpperBound(0); innerCtr++)
            {
               string otherChar = threeIs[innerCtr];
               Console.WriteLine("{0} (U+{1}) = {2} (U+{3}): {4}", 
                                 instanceChar, Convert.ToInt16(Char.Parse(instanceChar)).ToString("X4"), 
                                 otherChar, Convert.ToInt16(Char.Parse(otherChar)).ToString("X4"), 
                                 instanceChar.Equals(otherChar, sc));
            }
            Console.WriteLine();
         }
      }   
   }
}
// The example displays the following output:
//       The current culture is en-US.
//       
//       Comparisons using CurrentCulture:
//       i (U+0069) = i (U+0131): False
//       i (U+0069) = I (U+0049): False
//       
//       i (U+0131) = I (U+0049): False
//       
//       Comparisons using CurrentCultureIgnoreCase:
//       i (U+0069) = i (U+0131): False
//       i (U+0069) = I (U+0049): True
//       
//       i (U+0131) = I (U+0049): False
//       
//       Comparisons using InvariantCulture:
//       i (U+0069) = i (U+0131): False
//       i (U+0069) = I (U+0049): False
//       
//       i (U+0131) = I (U+0049): False
//       
//       Comparisons using InvariantCultureIgnoreCase:
//       i (U+0069) = i (U+0131): False
//       i (U+0069) = I (U+0049): True
//       
//       i (U+0131) = I (U+0049): False
//       
//       Comparisons using Ordinal:
//       i (U+0069) = i (U+0131): False
//       i (U+0069) = I (U+0049): False
//       
//       i (U+0131) = I (U+0049): False
//       
//       Comparisons using OrdinalIgnoreCase:
//       i (U+0069) = i (U+0131): False
//       i (U+0069) = I (U+0049): True
//       
//       i (U+0131) = I (U+0049): False
Class Sample
   Public Shared Sub Main() 
      ' Define a string array with the following three "I" characters:
      '      U+0069, U+0131, and U+0049.  
      Dim threeIs() As String = { "i", "ı", "I" }
      ' Define Type object representing StringComparison type.
      Dim scType As Type = GetType(StringComparison)  
      
      ' Show the current culture (for culture-sensitive string comparisons).
      Console.WriteLine("The current culture is {0}." & vbCrLf, _
                        System.Globalization.CultureInfo.CurrentCulture.Name)
        
      ' Perform comparisons using each StringComparison member. 
      For Each scName As String In [Enum].GetNames(scType)
         Dim sc As StringComparison = [Enum].Parse(scType, scName)
         Console.WriteLine("Comparisons using {0}:", sc)
         ' Compare each character in character array.
         For ctr As Integer = 0 To 1
            Dim instanceChar As String = threeIs(ctr)
            For innerCtr As Integer = ctr + 1 To threeIs.GetUpperBound(0)
               Dim otherChar As STring = threeIs(innerCtr)
               Console.WriteLine("{0} (U+{1}) = {2} (U+{3}): {4}", _
                                 instanceChar, Convert.ToInt16(Char.Parse(instanceChar)).ToString("X4"), _
                                 otherChar, Convert.ToInt16(Char.Parse(otherChar)).ToString("X4"), _
                                 instanceChar.Equals(otherChar, sc))
            Next
            Console.WriteLine()
         Next
      Next              
   End Sub
End Class
' The example displays the following output:
'       The current culture is en-US.
'       
'       Comparisons using CurrentCulture:
'       i (U+0069) = i (U+0131): False
'       i (U+0069) = I (U+0049): False
'       
'       i (U+0131) = I (U+0049): False
'       
'       Comparisons using CurrentCultureIgnoreCase:
'       i (U+0069) = i (U+0131): False
'       i (U+0069) = I (U+0049): True
'       
'       i (U+0131) = I (U+0049): False
'       
'       Comparisons using InvariantCulture:
'       i (U+0069) = i (U+0131): False
'       i (U+0069) = I (U+0049): False
'       
'       i (U+0131) = I (U+0049): False
'       
'       Comparisons using InvariantCultureIgnoreCase:
'       i (U+0069) = i (U+0131): False
'       i (U+0069) = I (U+0049): True
'       
'       i (U+0131) = I (U+0049): False
'       
'       Comparisons using Ordinal:
'       i (U+0069) = i (U+0131): False
'       i (U+0069) = I (U+0049): False
'       
'       i (U+0131) = I (U+0049): False
'       
'       Comparisons using OrdinalIgnoreCase:
'       i (U+0069) = i (U+0131): False
'       i (U+0069) = I (U+0049): True
'       
'       i (U+0131) = I (U+0049): False

次の例では、4 つの単語のセットを比較の各メンバーを使用して、StringComparison列挙体。The following example compares four sets of words by using each member of the StringComparison enumeration. 比較では、英語 (米国) とサーミ語 (上限スウェーデン) カルチャの規則を使用します。The comparisons use the conventions of the English (United States) and Sami (Upper Sweden) cultures. Sami (北スウェーデン) カルチャではなく、EN-US カルチャでの同等 encyclopædia"文字列"と"encyclopaedia"が考慮することに注意してください。Note that the strings "encyclopædia" and "encyclopaedia" are considered equivalent in the en-US culture but not in the Sami (Northern Sweden) culture.

using System;
using System.Globalization;
using System.Threading;

public class Example
{
   public static void Main()
   {
      String[] cultureNames = { "en-US", "se-SE" };
      String[] strings1 = { "case",  "encyclopædia",  
                            "encyclopædia", "Archæology" };
      String[] strings2 = { "Case", "encyclopaedia", 
                            "encyclopedia" , "ARCHÆOLOGY" };
      StringComparison[] comparisons = (StringComparison[]) Enum.GetValues(typeof(StringComparison));
      
      foreach (var cultureName in cultureNames) {
         Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture(cultureName);
         Console.WriteLine("Current Culture: {0}", CultureInfo.CurrentCulture.Name);
         for (int ctr = 0; ctr <= strings1.GetUpperBound(0); ctr++) {
            foreach (var comparison in comparisons) 
               Console.WriteLine("   {0} = {1} ({2}): {3}", strings1[ctr],
                                 strings2[ctr], comparison, 
                                 strings1[ctr].Equals(strings2[ctr], comparison));

            Console.WriteLine();         
         }
         Console.WriteLine();
      }
   }
}
// The example displays the following output:
//    Current Culture: en-US
//       case = Case (CurrentCulture): False
//       case = Case (CurrentCultureIgnoreCase): True
//       case = Case (InvariantCulture): False
//       case = Case (InvariantCultureIgnoreCase): True
//       case = Case (Ordinal): False
//       case = Case (OrdinalIgnoreCase): True
//    
//       encyclopædia = encyclopaedia (CurrentCulture): True
//       encyclopædia = encyclopaedia (CurrentCultureIgnoreCase): True
//       encyclopædia = encyclopaedia (InvariantCulture): True
//       encyclopædia = encyclopaedia (InvariantCultureIgnoreCase): True
//       encyclopædia = encyclopaedia (Ordinal): False
//       encyclopædia = encyclopaedia (OrdinalIgnoreCase): False
//    
//       encyclopædia = encyclopedia (CurrentCulture): False
//       encyclopædia = encyclopedia (CurrentCultureIgnoreCase): False
//       encyclopædia = encyclopedia (InvariantCulture): False
//       encyclopædia = encyclopedia (InvariantCultureIgnoreCase): False
//       encyclopædia = encyclopedia (Ordinal): False
//       encyclopædia = encyclopedia (OrdinalIgnoreCase): False
//    
//       Archæology = ARCHÆOLOGY (CurrentCulture): False
//       Archæology = ARCHÆOLOGY (CurrentCultureIgnoreCase): True
//       Archæology = ARCHÆOLOGY (InvariantCulture): False
//       Archæology = ARCHÆOLOGY (InvariantCultureIgnoreCase): True
//       Archæology = ARCHÆOLOGY (Ordinal): False
//       Archæology = ARCHÆOLOGY (OrdinalIgnoreCase): True
//    
//    
//    Current Culture: se-SE
//       case = Case (CurrentCulture): False
//       case = Case (CurrentCultureIgnoreCase): True
//       case = Case (InvariantCulture): False
//       case = Case (InvariantCultureIgnoreCase): True
//       case = Case (Ordinal): False
//       case = Case (OrdinalIgnoreCase): True
//    
//       encyclopædia = encyclopaedia (CurrentCulture): False
//       encyclopædia = encyclopaedia (CurrentCultureIgnoreCase): False
//       encyclopædia = encyclopaedia (InvariantCulture): True
//       encyclopædia = encyclopaedia (InvariantCultureIgnoreCase): True
//       encyclopædia = encyclopaedia (Ordinal): False
//       encyclopædia = encyclopaedia (OrdinalIgnoreCase): False
//    
//       encyclopædia = encyclopedia (CurrentCulture): False
//       encyclopædia = encyclopedia (CurrentCultureIgnoreCase): False
//       encyclopædia = encyclopedia (InvariantCulture): False
//       encyclopædia = encyclopedia (InvariantCultureIgnoreCase): False
//       encyclopædia = encyclopedia (Ordinal): False
//       encyclopædia = encyclopedia (OrdinalIgnoreCase): False
//    
//       Archæology = ARCHÆOLOGY (CurrentCulture): False
//       Archæology = ARCHÆOLOGY (CurrentCultureIgnoreCase): True
//       Archæology = ARCHÆOLOGY (InvariantCulture): False
//       Archæology = ARCHÆOLOGY (InvariantCultureIgnoreCase): True
//       Archæology = ARCHÆOLOGY (Ordinal): False
//       Archæology = ARCHÆOLOGY (OrdinalIgnoreCase): True
Imports System.Globalization
Imports System.Threading

Module Example
   Public Sub Main()
      Dim cultureNames() As String = { "en-US", "se-SE" }
      Dim strings1() As String = { "case",  "encyclopædia",  
                                   "encyclopædia", "Archæology" }
      Dim strings2() As String = { "Case", "encyclopaedia", 
                                   "encyclopedia" , "ARCHÆOLOGY" }
      Dim comparisons() As StringComparison = CType([Enum].GetValues(GetType(StringComparison)),
                                           StringComparison())
      
      For Each cultureName In cultureNames
         Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture(cultureName)
         Console.WriteLine("Current Culture: {0}", CultureInfo.CurrentCulture.Name)
         For ctr As Integer = 0 To strings1.GetUpperBound(0)
            For Each comparison In comparisons
               Console.WriteLine("   {0} = {1} ({2}): {3}", strings1(ctr),
                                 strings2(ctr), comparison, 
                                 strings1(ctr).Equals(strings2(ctr), comparison))
            Next
            Console.WriteLine()         
         Next
         Console.WriteLine()
      Next
   End Sub
End Module
' The example displays the following output:
'    Current Culture: en-US
'       case = Case (CurrentCulture): False
'       case = Case (CurrentCultureIgnoreCase): True
'       case = Case (InvariantCulture): False
'       case = Case (InvariantCultureIgnoreCase): True
'       case = Case (Ordinal): False
'       case = Case (OrdinalIgnoreCase): True
'    
'       encyclopædia = encyclopaedia (CurrentCulture): True
'       encyclopædia = encyclopaedia (CurrentCultureIgnoreCase): True
'       encyclopædia = encyclopaedia (InvariantCulture): True
'       encyclopædia = encyclopaedia (InvariantCultureIgnoreCase): True
'       encyclopædia = encyclopaedia (Ordinal): False
'       encyclopædia = encyclopaedia (OrdinalIgnoreCase): False
'    
'       encyclopædia = encyclopedia (CurrentCulture): False
'       encyclopædia = encyclopedia (CurrentCultureIgnoreCase): False
'       encyclopædia = encyclopedia (InvariantCulture): False
'       encyclopædia = encyclopedia (InvariantCultureIgnoreCase): False
'       encyclopædia = encyclopedia (Ordinal): False
'       encyclopædia = encyclopedia (OrdinalIgnoreCase): False
'    
'       Archæology = ARCHÆOLOGY (CurrentCulture): False
'       Archæology = ARCHÆOLOGY (CurrentCultureIgnoreCase): True
'       Archæology = ARCHÆOLOGY (InvariantCulture): False
'       Archæology = ARCHÆOLOGY (InvariantCultureIgnoreCase): True
'       Archæology = ARCHÆOLOGY (Ordinal): False
'       Archæology = ARCHÆOLOGY (OrdinalIgnoreCase): True
'    
'    
'    Current Culture: se-SE
'       case = Case (CurrentCulture): False
'       case = Case (CurrentCultureIgnoreCase): True
'       case = Case (InvariantCulture): False
'       case = Case (InvariantCultureIgnoreCase): True
'       case = Case (Ordinal): False
'       case = Case (OrdinalIgnoreCase): True
'    
'       encyclopædia = encyclopaedia (CurrentCulture): False
'       encyclopædia = encyclopaedia (CurrentCultureIgnoreCase): False
'       encyclopædia = encyclopaedia (InvariantCulture): True
'       encyclopædia = encyclopaedia (InvariantCultureIgnoreCase): True
'       encyclopædia = encyclopaedia (Ordinal): False
'       encyclopædia = encyclopaedia (OrdinalIgnoreCase): False
'    
'       encyclopædia = encyclopedia (CurrentCulture): False
'       encyclopædia = encyclopedia (CurrentCultureIgnoreCase): False
'       encyclopædia = encyclopedia (InvariantCulture): False
'       encyclopædia = encyclopedia (InvariantCultureIgnoreCase): False
'       encyclopædia = encyclopedia (Ordinal): False
'       encyclopædia = encyclopedia (OrdinalIgnoreCase): False
'    
'       Archæology = ARCHÆOLOGY (CurrentCulture): False
'       Archæology = ARCHÆOLOGY (CurrentCultureIgnoreCase): True
'       Archæology = ARCHÆOLOGY (InvariantCulture): False
'       Archæology = ARCHÆOLOGY (InvariantCultureIgnoreCase): True
'       Archæology = ARCHÆOLOGY (Ordinal): False
'       Archæology = ARCHÆOLOGY (OrdinalIgnoreCase): True

注釈

comparisonTypeパラメーターは、比較では、現在またはインバリアント カルチャを使用する必要があります、かどうかを優先または比較対象となる 2 つの文字列の大文字と小文字を無視または word または序数の並べ替え規則を使用して、ことを示します。The comparisonType parameter indicates whether the comparison should use the current or invariant culture, honor or ignore the case of the two strings being compared, or use word or ordinal sort rules.

こちらもご覧ください

Equals(String, String) Equals(String, String) Equals(String, String) Equals(String, String)

指定した 2 つの String オブジェクトの値が同一かどうかを判断します。Determines whether two specified String objects have the same value.

public:
 static bool Equals(System::String ^ a, System::String ^ b);
public static bool Equals (string a, string b);
static member Equals : string * string -> bool
Public Shared Function Equals (a As String, b As String) As Boolean

パラメーター

a
String String String String

比較する最初の文字列または nullThe first string to compare, or null.

b
String String String String

比較する 2 番目の文字列または nullThe second string to compare, or null.

戻り値

a の値が b の値と同じ場合は true。それ以外の場合は falsetrue if the value of a is the same as the value of b; otherwise, false. ab の両方が null の場合、メソッドは true を返します。If both a and b are null, the method returns true.

次の例で、Equalsメソッド。The following example demonstrates the Equals method.

// Sample for String::Equals(Object)
//            String::Equals(String)
//            String::Equals(String, String)
using namespace System;
using namespace System::Text;
int main()
{
   StringBuilder^ sb = gcnew StringBuilder( "abcd" );
   String^ str1 = "abcd";
   String^ str2 = nullptr;
   Object^ o2 = nullptr;
   Console::WriteLine();
   Console::WriteLine( " *  The value of String str1 is '{0}'.", str1 );
   Console::WriteLine( " *  The value of StringBuilder sb is '{0}'.", sb );
   Console::WriteLine();
   Console::WriteLine( "1a) String::Equals(Object). Object is a StringBuilder, not a String." );
   Console::WriteLine( "    Is str1 equal to sb?: {0}", str1->Equals( sb ) );
   Console::WriteLine();
   Console::WriteLine( "1b) String::Equals(Object). Object is a String." );
   str2 = sb->ToString();
   o2 = str2;
   Console::WriteLine( " *  The value of Object o2 is '{0}'.", o2 );
   Console::WriteLine( "    Is str1 equal to o2?: {0}", str1->Equals( o2 ) );
   Console::WriteLine();
   Console::WriteLine( " 2) String::Equals(String)" );
   Console::WriteLine( " *  The value of String str2 is '{0}'.", str2 );
   Console::WriteLine( "    Is str1 equal to str2?: {0}", str1->Equals( str2 ) );
   Console::WriteLine();
   Console::WriteLine( " 3) String::Equals(String, String)" );
   Console::WriteLine( "    Is str1 equal to str2?: {0}", String::Equals( str1, str2 ) );
}

/*
This example produces the following results:

 *  The value of String str1 is 'abcd'.
 *  The value of StringBuilder sb is 'abcd'.

1a) String::Equals(Object). Object is a StringBuilder, not a String.
    Is str1 equal to sb?: False

1b) String::Equals(Object). Object is a String.
 *  The value of Object o2 is 'abcd'.
    Is str1 equal to o2?: True

 2) String::Equals(String)
 *  The value of String str2 is 'abcd'.
    Is str1 equal to str2?: True

 3) String::Equals(String, String)
    Is str1 equal to str2?: True
*/
// Sample for String.Equals(Object)
//            String.Equals(String)
//            String.Equals(String, String)
using System;
using System.Text;

class Sample {
    public static void Main() {
    StringBuilder sb = new StringBuilder("abcd");
    String      str1 = "abcd";
    String      str2 = null;
    Object	o2   = null;

    Console.WriteLine();
    Console.WriteLine(" *  The value of String str1 is '{0}'.", str1);
    Console.WriteLine(" *  The value of StringBuilder sb is '{0}'.", sb.ToString());

    Console.WriteLine();
    Console.WriteLine("1a) String.Equals(Object). Object is a StringBuilder, not a String.");
    Console.WriteLine("    Is str1 equal to sb?: {0}", str1.Equals(sb));

    Console.WriteLine();
    Console.WriteLine("1b) String.Equals(Object). Object is a String.");
    str2 = sb.ToString();
    o2   = str2;
    Console.WriteLine(" *  The value of Object o2 is '{0}'.", o2);
    Console.WriteLine("    Is str1 equal to o2?: {0}", str1.Equals(o2));

    Console.WriteLine();
    Console.WriteLine(" 2) String.Equals(String)");
    Console.WriteLine(" *  The value of String str2 is '{0}'.", str2);
    Console.WriteLine("    Is str1 equal to str2?: {0}", str1.Equals(str2));

    Console.WriteLine();
    Console.WriteLine(" 3) String.Equals(String, String)");
    Console.WriteLine("    Is str1 equal to str2?: {0}", String.Equals(str1, str2));
    }
}
/*
This example produces the following results:

 *  The value of String str1 is 'abcd'.
 *  The value of StringBuilder sb is 'abcd'.

1a) String.Equals(Object). Object is a StringBuilder, not a String.
    Is str1 equal to sb?: False

1b) String.Equals(Object). Object is a String.
 *  The value of Object o2 is 'abcd'.
    Is str1 equal to o2?: True

 2) String.Equals(String)
 *  The value of String str2 is 'abcd'.
    Is str1 equal to str2?: True

 3) String.Equals(String, String)
    Is str1 equal to str2?: True
*/
' Sample for String.Equals(Object)
'            String.Equals(String)
'            String.Equals(String, String)
Imports System
Imports System.Text

Class Sample
   Public Shared Sub Main()
      Dim sb As New StringBuilder("abcd")
      Dim str1 As [String] = "abcd"
      Dim str2 As [String] = Nothing
      Dim o2 As [Object] = Nothing
      
      Console.WriteLine()
      Console.WriteLine(" *  The value of String str1 is '{0}'.", str1)
      Console.WriteLine(" *  The value of StringBuilder sb is '{0}'.", sb.ToString())
      
      Console.WriteLine()
      Console.WriteLine("1a) String.Equals(Object). Object is a StringBuilder, not a String.")
      Console.WriteLine("    Is str1 equal to sb?: {0}", str1.Equals(sb))
      
      Console.WriteLine()
      Console.WriteLine("1b) String.Equals(Object). Object is a String.")
      str2 = sb.ToString()
      o2 = str2
      Console.WriteLine(" *  The value of Object o2 is '{0}'.", o2)
      Console.WriteLine("    Is str1 equal to o2?: {0}", str1.Equals(o2))
      
      Console.WriteLine()
      Console.WriteLine(" 2) String.Equals(String)")
      Console.WriteLine(" *  The value of String str2 is '{0}'.", str2)
      Console.WriteLine("    Is str1 equal to str2?: {0}", str1.Equals(str2))
      
      Console.WriteLine()
      Console.WriteLine(" 3) String.Equals(String, String)")
      Console.WriteLine("    Is str1 equal to str2?: {0}", [String].Equals(str1, str2))
   End Sub 'Main
End Class 'Sample
'
'This example produces the following results:
'
' *  The value of String str1 is 'abcd'.
' *  The value of StringBuilder sb is 'abcd'.
'
'1a) String.Equals(Object). Object is a StringBuilder, not a String.
'    Is str1 equal to sb?: False
'
'1b) String.Equals(Object). Object is a String.
' *  The value of Object o2 is 'abcd'.
'    Is str1 equal to o2?: True
'
' 2) String.Equals(String)
' *  The value of String str2 is 'abcd'.
'    Is str1 equal to str2?: True
'
' 3) String.Equals(String, String)
'    Is str1 equal to str2?: True
'

注釈

このメソッドは、序数に基づく (大文字と小文字およびカルチャに依存しない) 比較を実行します。This method performs an ordinal (case-sensitive and culture-insensitive) comparison.

こちらもご覧ください

Equals(String, String, StringComparison) Equals(String, String, StringComparison) Equals(String, String, StringComparison) Equals(String, String, StringComparison)

指定した 2 つの String オブジェクトの値が同一かどうかを判断します。Determines whether two specified String objects have the same value. 比較に使用するカルチャ、大文字と小文字の区別、および、並べ替え規則をパラメーターで指定します。A parameter specifies the culture, case, and sort rules used in the comparison.

public:
 static bool Equals(System::String ^ a, System::String ^ b, StringComparison comparisonType);
public static bool Equals (string a, string b, StringComparison comparisonType);
static member Equals : string * string * StringComparison -> bool
Public Shared Function Equals (a As String, b As String, comparisonType As StringComparison) As Boolean

パラメーター

a
String String String String

比較する最初の文字列または nullThe first string to compare, or null.

b
String String String String

比較する 2 番目の文字列または nullThe second string to compare, or null.

comparisonType
StringComparison StringComparison StringComparison StringComparison

比較の規則を指定する列挙値の 1 つ。One of the enumeration values that specifies the rules for the comparison.

戻り値

true パラメーターの値が a パラメーターの値に等しい場合は b。それ以外の場合は falsetrue if the value of the a parameter is equal to the value of the b parameter; otherwise, false.

例外

comparisonTypeStringComparison 値ではありません。comparisonType is not a StringComparison value.

次の例では、4 つの単語のセットを比較の各メンバーを使用して、StringComparison列挙体。The following example compares four sets of words by using each member of the StringComparison enumeration. 比較では、英語 (米国) とサーミ語 (上限スウェーデン) カルチャの規則を使用します。The comparisons use the conventions of the English (United States) and Sami (Upper Sweden) cultures. Sami (北スウェーデン) カルチャではなく、EN-US カルチャでの同等 encyclopædia"文字列"と"encyclopaedia"が考慮することに注意してください。Note that the strings "encyclopædia" and "encyclopaedia" are considered equivalent in the en-US culture but not in the Sami (Northern Sweden) culture.

using System;
using System.Globalization;
using System.Threading;

public class Example
{
   public static void Main()
   {
      String[] cultureNames = { "en-US", "se-SE" };
      String[] strings1 = { "case",  "encyclopædia",  
                            "encyclopædia", "Archæology" };
      String[] strings2 = { "Case", "encyclopaedia", 
                            "encyclopedia" , "ARCHÆOLOGY" };
      StringComparison[] comparisons = (StringComparison[]) Enum.GetValues(typeof(StringComparison));
      
      foreach (var cultureName in cultureNames) {
         Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture(cultureName);
         Console.WriteLine("Current Culture: {0}", CultureInfo.CurrentCulture.Name);
         for (int ctr = 0; ctr <= strings1.GetUpperBound(0); ctr++) {
            foreach (var comparison in comparisons) 
               Console.WriteLine("   {0} = {1} ({2}): {3}", strings1[ctr],
                                 strings2[ctr], comparison, 
                                 String.Equals(strings1[ctr], strings2[ctr], comparison));

            Console.WriteLine();         
         }
         Console.WriteLine();
      }
   }
}
// The example displays the following output:
//    Current Culture: en-US
//       case = Case (CurrentCulture): False
//       case = Case (CurrentCultureIgnoreCase): True
//       case = Case (InvariantCulture): False
//       case = Case (InvariantCultureIgnoreCase): True
//       case = Case (Ordinal): False
//       case = Case (OrdinalIgnoreCase): True
//    
//       encyclopædia = encyclopaedia (CurrentCulture): True
//       encyclopædia = encyclopaedia (CurrentCultureIgnoreCase): True
//       encyclopædia = encyclopaedia (InvariantCulture): True
//       encyclopædia = encyclopaedia (InvariantCultureIgnoreCase): True
//       encyclopædia = encyclopaedia (Ordinal): False
//       encyclopædia = encyclopaedia (OrdinalIgnoreCase): False
//    
//       encyclopædia = encyclopedia (CurrentCulture): False
//       encyclopædia = encyclopedia (CurrentCultureIgnoreCase): False
//       encyclopædia = encyclopedia (InvariantCulture): False
//       encyclopædia = encyclopedia (InvariantCultureIgnoreCase): False
//       encyclopædia = encyclopedia (Ordinal): False
//       encyclopædia = encyclopedia (OrdinalIgnoreCase): False
//    
//       Archæology = ARCHÆOLOGY (CurrentCulture): False
//       Archæology = ARCHÆOLOGY (CurrentCultureIgnoreCase): True
//       Archæology = ARCHÆOLOGY (InvariantCulture): False
//       Archæology = ARCHÆOLOGY (InvariantCultureIgnoreCase): True
//       Archæology = ARCHÆOLOGY (Ordinal): False
//       Archæology = ARCHÆOLOGY (OrdinalIgnoreCase): True
//    
//    
//    Current Culture: se-SE
//       case = Case (CurrentCulture): False
//       case = Case (CurrentCultureIgnoreCase): True
//       case = Case (InvariantCulture): False
//       case = Case (InvariantCultureIgnoreCase): True
//       case = Case (Ordinal): False
//       case = Case (OrdinalIgnoreCase): True
//    
//       encyclopædia = encyclopaedia (CurrentCulture): False
//       encyclopædia = encyclopaedia (CurrentCultureIgnoreCase): False
//       encyclopædia = encyclopaedia (InvariantCulture): True
//       encyclopædia = encyclopaedia (InvariantCultureIgnoreCase): True
//       encyclopædia = encyclopaedia (Ordinal): False
//       encyclopædia = encyclopaedia (OrdinalIgnoreCase): False
//    
//       encyclopædia = encyclopedia (CurrentCulture): False
//       encyclopædia = encyclopedia (CurrentCultureIgnoreCase): False
//       encyclopædia = encyclopedia (InvariantCulture): False
//       encyclopædia = encyclopedia (InvariantCultureIgnoreCase): False
//       encyclopædia = encyclopedia (Ordinal): False
//       encyclopædia = encyclopedia (OrdinalIgnoreCase): False
//    
//       Archæology = ARCHÆOLOGY (CurrentCulture): False
//       Archæology = ARCHÆOLOGY (CurrentCultureIgnoreCase): True
//       Archæology = ARCHÆOLOGY (InvariantCulture): False
//       Archæology = ARCHÆOLOGY (InvariantCultureIgnoreCase): True
//       Archæology = ARCHÆOLOGY (Ordinal): False
//       Archæology = ARCHÆOLOGY (OrdinalIgnoreCase): True
Imports System.Globalization
Imports System.Threading

Module Example
   Public Sub Main()
      Dim cultureNames() As String = { "en-US", "se-SE" }
      Dim strings1() As String = { "case",  "encyclopædia",  
                                   "encyclopædia", "Archæology" }
      Dim strings2() As String = { "Case", "encyclopaedia", 
                                   "encyclopedia" , "ARCHÆOLOGY" }
      Dim comparisons() As StringComparison = CType([Enum].GetValues(GetType(StringComparison)),
                                           StringComparison())
      
      For Each cultureName In cultureNames
         Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture(cultureName)
         Console.WriteLine("Current Culture: {0}", CultureInfo.CurrentCulture.Name)
         For ctr As Integer = 0 To strings1.GetUpperBound(0)
            For Each comparison In comparisons
               Console.WriteLine("   {0} = {1} ({2}): {3}", strings1(ctr),
                                 strings2(ctr), comparison, 
                                 String.Equals(strings1(ctr), strings2(ctr), comparison))
            Next
            Console.WriteLine()         
         Next
         Console.WriteLine()
      Next
   End Sub
End Module
' The example displays the following output:
'    Current Culture: en-US
'       case = Case (CurrentCulture): False
'       case = Case (CurrentCultureIgnoreCase): True
'       case = Case (InvariantCulture): False
'       case = Case (InvariantCultureIgnoreCase): True
'       case = Case (Ordinal): False
'       case = Case (OrdinalIgnoreCase): True
'    
'       encyclopædia = encyclopaedia (CurrentCulture): True
'       encyclopædia = encyclopaedia (CurrentCultureIgnoreCase): True
'       encyclopædia = encyclopaedia (InvariantCulture): True
'       encyclopædia = encyclopaedia (InvariantCultureIgnoreCase): True
'       encyclopædia = encyclopaedia (Ordinal): False
'       encyclopædia = encyclopaedia (OrdinalIgnoreCase): False
'    
'       encyclopædia = encyclopedia (CurrentCulture): False
'       encyclopædia = encyclopedia (CurrentCultureIgnoreCase): False
'       encyclopædia = encyclopedia (InvariantCulture): False
'       encyclopædia = encyclopedia (InvariantCultureIgnoreCase): False
'       encyclopædia = encyclopedia (Ordinal): False
'       encyclopædia = encyclopedia (OrdinalIgnoreCase): False
'    
'       Archæology = ARCHÆOLOGY (CurrentCulture): False
'       Archæology = ARCHÆOLOGY (CurrentCultureIgnoreCase): True
'       Archæology = ARCHÆOLOGY (InvariantCulture): False
'       Archæology = ARCHÆOLOGY (InvariantCultureIgnoreCase): True
'       Archæology = ARCHÆOLOGY (Ordinal): False
'       Archæology = ARCHÆOLOGY (OrdinalIgnoreCase): True
'    
'    
'    Current Culture: se-SE
'       case = Case (CurrentCulture): False
'       case = Case (CurrentCultureIgnoreCase): True
'       case = Case (InvariantCulture): False
'       case = Case (InvariantCultureIgnoreCase): True
'       case = Case (Ordinal): False
'       case = Case (OrdinalIgnoreCase): True
'    
'       encyclopædia = encyclopaedia (CurrentCulture): False
'       encyclopædia = encyclopaedia (CurrentCultureIgnoreCase): False
'       encyclopædia = encyclopaedia (InvariantCulture): True
'       encyclopædia = encyclopaedia (InvariantCultureIgnoreCase): True
'       encyclopædia = encyclopaedia (Ordinal): False
'       encyclopædia = encyclopaedia (OrdinalIgnoreCase): False
'    
'       encyclopædia = encyclopedia (CurrentCulture): False
'       encyclopædia = encyclopedia (CurrentCultureIgnoreCase): False
'       encyclopædia = encyclopedia (InvariantCulture): False
'       encyclopædia = encyclopedia (InvariantCultureIgnoreCase): False
'       encyclopædia = encyclopedia (Ordinal): False
'       encyclopædia = encyclopedia (OrdinalIgnoreCase): False
'    
'       Archæology = ARCHÆOLOGY (CurrentCulture): False
'       Archæology = ARCHÆOLOGY (CurrentCultureIgnoreCase): True
'       Archæology = ARCHÆOLOGY (InvariantCulture): False
'       Archæology = ARCHÆOLOGY (InvariantCultureIgnoreCase): True
'       Archæology = ARCHÆOLOGY (Ordinal): False
'       Archæology = ARCHÆOLOGY (OrdinalIgnoreCase): True

注釈

comparisonTypeパラメーターは、比較では、現在またはインバリアント カルチャを使用する必要があります、かどうかを優先または比較対象となる 2 つの文字列の大文字と小文字を無視または word または序数の並べ替え規則を使用して、ことを示します。The comparisonType parameter indicates whether the comparison should use the current or invariant culture, honor or ignore the case of the two strings being compared, or use word or ordinal sort rules.

こちらもご覧ください

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

このインスタンスと、指定したオブジェクトの値が同一かどうかを判断します。String オブジェクトを指定する必要があります。Determines whether this instance and a specified object, which must also be a String object, have the same value.

public:
 override bool Equals(System::Object ^ obj);
public override bool Equals (object obj);
override this.Equals : obj -> bool
Public Overrides Function Equals (obj As Object) As Boolean

パラメーター

obj
Object Object Object Object

このインスタンスと比較する文字列。The string to compare to this instance.

戻り値

trueobj で、このインスタンスと同じ値を保持している場合は String。それ以外の場合は falsetrue if obj is a String and its value is the same as this instance; otherwise, false. objnull の場合、メソッドは false を返します。If obj is null, the method returns false.

次の例で、Equalsメソッド。The following example demonstrates the Equals method.

// Sample for String::Equals(Object)
//            String::Equals(String)
//            String::Equals(String, String)
using namespace System;
using namespace System::Text;
int main()
{
   StringBuilder^ sb = gcnew StringBuilder( "abcd" );
   String^ str1 = "abcd";
   String^ str2 = nullptr;
   Object^ o2 = nullptr;
   Console::WriteLine();
   Console::WriteLine( " *  The value of String str1 is '{0}'.", str1 );
   Console::WriteLine( " *  The value of StringBuilder sb is '{0}'.", sb );
   Console::WriteLine();
   Console::WriteLine( "1a) String::Equals(Object). Object is a StringBuilder, not a String." );
   Console::WriteLine( "    Is str1 equal to sb?: {0}", str1->Equals( sb ) );
   Console::WriteLine();
   Console::WriteLine( "1b) String::Equals(Object). Object is a String." );
   str2 = sb->ToString();
   o2 = str2;
   Console::WriteLine( " *  The value of Object o2 is '{0}'.", o2 );
   Console::WriteLine( "    Is str1 equal to o2?: {0}", str1->Equals( o2 ) );
   Console::WriteLine();
   Console::WriteLine( " 2) String::Equals(String)" );
   Console::WriteLine( " *  The value of String str2 is '{0}'.", str2 );
   Console::WriteLine( "    Is str1 equal to str2?: {0}", str1->Equals( str2 ) );
   Console::WriteLine();
   Console::WriteLine( " 3) String::Equals(String, String)" );
   Console::WriteLine( "    Is str1 equal to str2?: {0}", String::Equals( str1, str2 ) );
}

/*
This example produces the following results:

 *  The value of String str1 is 'abcd'.
 *  The value of StringBuilder sb is 'abcd'.

1a) String::Equals(Object). Object is a StringBuilder, not a String.
    Is str1 equal to sb?: False

1b) String::Equals(Object). Object is a String.
 *  The value of Object o2 is 'abcd'.
    Is str1 equal to o2?: True

 2) String::Equals(String)
 *  The value of String str2 is 'abcd'.
    Is str1 equal to str2?: True

 3) String::Equals(String, String)
    Is str1 equal to str2?: True
*/
// Sample for String.Equals(Object)
//            String.Equals(String)
//            String.Equals(String, String)
using System;
using System.Text;

class Sample {
    public static void Main() {
    StringBuilder sb = new StringBuilder("abcd");
    String      str1 = "abcd";
    String      str2 = null;
    Object	o2   = null;

    Console.WriteLine();
    Console.WriteLine(" *  The value of String str1 is '{0}'.", str1);
    Console.WriteLine(" *  The value of StringBuilder sb is '{0}'.", sb.ToString());

    Console.WriteLine();
    Console.WriteLine("1a) String.Equals(Object). Object is a StringBuilder, not a String.");
    Console.WriteLine("    Is str1 equal to sb?: {0}", str1.Equals(sb));

    Console.WriteLine();
    Console.WriteLine("1b) String.Equals(Object). Object is a String.");
    str2 = sb.ToString();
    o2   = str2;
    Console.WriteLine(" *  The value of Object o2 is '{0}'.", o2);
    Console.WriteLine("    Is str1 equal to o2?: {0}", str1.Equals(o2));

    Console.WriteLine();
    Console.WriteLine(" 2) String.Equals(String)");
    Console.WriteLine(" *  The value of String str2 is '{0}'.", str2);
    Console.WriteLine("    Is str1 equal to str2?: {0}", str1.Equals(str2));

    Console.WriteLine();
    Console.WriteLine(" 3) String.Equals(String, String)");
    Console.WriteLine("    Is str1 equal to str2?: {0}", String.Equals(str1, str2));
    }
}
/*
This example produces the following results:

 *  The value of String str1 is 'abcd'.
 *  The value of StringBuilder sb is 'abcd'.

1a) String.Equals(Object). Object is a StringBuilder, not a String.
    Is str1 equal to sb?: False

1b) String.Equals(Object). Object is a String.
 *  The value of Object o2 is 'abcd'.
    Is str1 equal to o2?: True

 2) String.Equals(String)
 *  The value of String str2 is 'abcd'.
    Is str1 equal to str2?: True

 3) String.Equals(String, String)
    Is str1 equal to str2?: True
*/
' Sample for String.Equals(Object)
'            String.Equals(String)
'            String.Equals(String, String)
Imports System
Imports System.Text

Class Sample
   Public Shared Sub Main()
      Dim sb As New StringBuilder("abcd")
      Dim str1 As [String] = "abcd"
      Dim str2 As [String] = Nothing
      Dim o2 As [Object] = Nothing
      
      Console.WriteLine()
      Console.WriteLine(" *  The value of String str1 is '{0}'.", str1)
      Console.WriteLine(" *  The value of StringBuilder sb is '{0}'.", sb.ToString())
      
      Console.WriteLine()
      Console.WriteLine("1a) String.Equals(Object). Object is a StringBuilder, not a String.")
      Console.WriteLine("    Is str1 equal to sb?: {0}", str1.Equals(sb))
      
      Console.WriteLine()
      Console.WriteLine("1b) String.Equals(Object). Object is a String.")
      str2 = sb.ToString()
      o2 = str2
      Console.WriteLine(" *  The value of Object o2 is '{0}'.", o2)
      Console.WriteLine("    Is str1 equal to o2?: {0}", str1.Equals(o2))
      
      Console.WriteLine()
      Console.WriteLine(" 2) String.Equals(String)")
      Console.WriteLine(" *  The value of String str2 is '{0}'.", str2)
      Console.WriteLine("    Is str1 equal to str2?: {0}", str1.Equals(str2))
      
      Console.WriteLine()
      Console.WriteLine(" 3) String.Equals(String, String)")
      Console.WriteLine("    Is str1 equal to str2?: {0}", [String].Equals(str1, str2))
   End Sub 'Main
End Class 'Sample
'
'This example produces the following results:
'
' *  The value of String str1 is 'abcd'.
' *  The value of StringBuilder sb is 'abcd'.
'
'1a) String.Equals(Object). Object is a StringBuilder, not a String.
'    Is str1 equal to sb?: False
'
'1b) String.Equals(Object). Object is a String.
' *  The value of Object o2 is 'abcd'.
'    Is str1 equal to o2?: True
'
' 2) String.Equals(String)
' *  The value of String str2 is 'abcd'.
'    Is str1 equal to str2?: True
'
' 3) String.Equals(String, String)
'    Is str1 equal to str2?: True
'

注釈

このメソッドは、序数に基づく (大文字と小文字およびカルチャに依存しない) 比較を実行します。This method performs an ordinal (case-sensitive and culture-insensitive) comparison.

こちらもご覧ください

Equals(String) Equals(String) Equals(String) Equals(String)

このインスタンスと、指定した別の String の値が同一かどうかを判断します。Determines whether this instance and another specified String object have the same value.

public:
 virtual bool Equals(System::String ^ value);
public bool Equals (string value);
override this.Equals : string -> bool
Public Function Equals (value As String) As Boolean

パラメーター

value
String String String String

このインスタンスと比較する文字列。The string to compare to this instance.

戻り値

true パラメーターの値がこのインスタンスの値と同じ場合は value。それ以外の場合は falsetrue if the value of the value parameter is the same as the value of this instance; otherwise, false. valuenull の場合、メソッドは false を返します。If value is null, the method returns false.

実装

次の例で、Equalsメソッド。The following example demonstrates the Equals method. 同等の用語を等価な小文字、等価な大文字、および単語 LATIN 小さな文字ドット I が含まれていますを持つタイトル大文字と小文字の単語"File"と比較します (U + 0131) ではなくラテン小さな文字 I (u+0069)。It compares the title-cased word "File" with an equivalent word, its lowercase equivalent, its uppercase equivalent, and a word that contains LATIN SMALL LETTER DOTLESS I (U+0131) instead of LATIN SMALL LETTER I (U+0069). Equals(String)メソッドは、序数に基づく比較を実行、同一の単語との比較だけを返しますtrueします。Because the Equals(String) method performs an ordinal comparison, only the comparison with an identical word returns true.

using System;

public class Example
{
   public static void Main()
   {
      Console.OutputEncoding = System.Text.Encoding.UTF8;
      string word = "File";
      string[] others = { word.ToLower(), word, word.ToUpper(), "Fıle" };
      foreach (string other in others)
      {
         if (word.Equals(other)) 
            Console.WriteLine("{0} = {1}", word, other);
         else
            Console.WriteLine("{0} {1} {2}", word, '\u2260', other);
      }        
   }
}
// The example displays the following output:
//       File ≠ file
//       File = File
//       File ≠ FILE
//       File ≠ Fıle
Module Example
   Public Sub Main()
      Console.OutputEncoding = System.Text.Encoding.UTF8
      
      Dim word As String = "File"
      Dim others() As String = { word.ToLower(), word, word.ToUpper(), _
                                 "Fıle" }
      For Each other As String In others
         If word.Equals(other) Then 
            Console.WriteLine("{0} = {1}", word, other)
         Else
            Console.WriteLine("{0} {1} {2}", word, ChrW(&H2260), other)
         End If      
      Next        
   End Sub
End Module
' The example displays the following output:
'       File ≠ file
'       File = File
'       File ≠ FILE
'       File ≠ Fıle

注釈

このメソッドは、序数に基づく (大文字と小文字およびカルチャに依存しない) 比較を実行します。This method performs an ordinal (case-sensitive and culture-insensitive) comparison.

こちらもご覧ください

適用対象