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String.Inequality(String, String) Operator

Definition

Determines whether two specified strings have different values.

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 op_Inequality : string * string -> bool
Public Shared Operator != (a As String, b As String) As Boolean

Parameters

a
String

The first string to compare, or null.

b
String

The second string to compare, or null.

Returns

true if the value of a is different from the value of b; otherwise, false.

Examples

The following example demonstrates the inequality operator.

// Example for the String Inequality 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 Inequality operator\n"
   "generates the following output.\n" );
   CompareAndDisplay( "ijkl" );
   CompareAndDisplay( "ABCD" );
   CompareAndDisplay( "abcd" );
}

/*
This example of the String Inequality operator
generates the following output.

"abcd" != "ijkl" ?  True
"abcd" != "ABCD" ?  True
"abcd" != "abcd" ?  False
*/
// Example for the String Inequality operator.
using System;

class InequalityOp 
{
    public static void Main() 
    {
        Console.WriteLine( 
            "This example of the String Inequality 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 Inequality operator
generates the following output.

"abcd" != "ijkl" ?  True
"abcd" != "ABCD" ?  True
"abcd" != "abcd" ?  False
*/
// Example for the String Inequality operator.
printfn "This example of the String Inequality 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 Inequality operator
generates the following output.

"abcd" <> "ijkl" ?  True
"abcd" <> "ABCD" ?  True
"abcd" <> "abcd" ?  False
*)

Remarks

The Inequality method defines the operation of the inequality operator for the String class. It enables code such as that shown in the Examples section.

The Inequality 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 inequality operator as a call to the Inequality method. Instead, the inequality operator wraps a call to the Operators.CompareString method.

Applies to