String.Equality(String, String) Operator
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Determines whether two specified strings have the same value.
public:
static bool operator ==(System::String ^ a, System::String ^ b);
public static bool operator == (string a, string b);
public static bool operator == (string? a, string? b);
static member ( = ) : string * string -> bool
Public Shared Operator == (a As String, b As String) As Boolean
- a
- String
The first string to compare, or null
.
- b
- String
The second string to compare, or null
.
true
if the value of a
is the same as the value of b
; otherwise, false
.
The following example demonstrates the equality operator.
// Example for the String Equality operator.
using namespace System;
void CompareAndDisplay( String^ Comparand )
{
String^ Lower = "abcd";
Console::WriteLine( "\"{0}\" == \"{1}\" ? {2}", Lower, Comparand, Lower == Comparand );
}
int main()
{
Console::WriteLine( "This example of the String Equality operator\n"
"generates the following output.\n" );
CompareAndDisplay( "ijkl" );
CompareAndDisplay( "ABCD" );
CompareAndDisplay( "abcd" );
}
/*
This example of the String Equality operator
generates the following output.
"abcd" == "ijkl" ? False
"abcd" == "ABCD" ? False
"abcd" == "abcd" ? True
*/
// Example for the String Equality operator.
using System;
class EqualityOp
{
public static void Main()
{
Console.WriteLine(
"This example of the String Equality operator\n" +
"generates the following output.\n" );
CompareAndDisplay( "ijkl" );
CompareAndDisplay( "ABCD" );
CompareAndDisplay( "abcd" );
}
static void CompareAndDisplay( string Comparand )
{
String Lower = "abcd";
Console.WriteLine(
"\"{0}\" == \"{1}\" ? {2}",
Lower, Comparand, Lower == Comparand );
}
}
/*
This example of the String Equality operator
generates the following output.
"abcd" == "ijkl" ? False
"abcd" == "ABCD" ? False
"abcd" == "abcd" ? True
*/
// Example for the String Equality operator.
printfn "This example of the String Equality operator\ngenerates the following output.\n"
let compareAndDisplay comparand =
let lower = "abcd"
printfn $"\"%s{lower}\" == \"%s{comparand}\" ? {lower = comparand}"
compareAndDisplay "ijkl"
compareAndDisplay "ABCD"
compareAndDisplay "abcd"
(*
This example of the String Equality operator
generates the following output.
"abcd" == "ijkl" ? False
"abcd" == "ABCD" ? False
"abcd" == "abcd" ? True
*)
The Equality method defines the operation of the equality operator for the String class. It enables code such as that shown in the Example section. The operator, in turn, calls the static Equals(String, String) method, which performs an ordinal (case-sensitive and culture-insensitive) comparison.
Note
The Visual Basic compiler does not resolve the equality operator as a call to the Equality method. Instead, the equality operator wraps a call to the Operators.CompareString method.
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2.0, 2.1 |
UWP | 10.0 |
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