How to: Test for Equality
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How to: Test for Equality (C++/CLI)

In the following sample, a test for equality using Managed Extensions for C++ is based on what the pointers point to.

For more information, see Breaking Changes in the Visual C++ 2005 Compiler.

// mcppv2_equality_test.cpp
// compile with: /clr:oldSyntax /LD
using namespace System;

bool Test1() {
   String * str1 = S"test";
   String * str2 = S"test";
   return (str1 == str2);
}

The IL for this program shows that the return value is implemented with this instruction:

  IL_0012:  ceq

which compares the addresses of the two String objects.

Using the new syntax,

// mcppv2_equality_test_2.cpp
// compile with: /clr /LD
using namespace System;

bool Test1() {
   String ^ str1 = "test";
   String ^ str2 = "test";
   return (str1 == str2);
}

The IL for this program shows that the return value is implemented with a call to op_Equality.

  IL_0012:  call       bool [mscorlib]System.String::op_Equality(string,
                                                                 string)
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