Why don't we use new operator while initializing a string?

Question

I was asked this question in an interview: Is string a reference type or a value type.

I said its a reference type. Then he asked me why don\'t we use new operator

Answer 1

Nope. The compiler does not change the construction. What type should the constructor argument be? String? ;-)

String literals are constants without a name.

In addition, you can initialize any class with a string literal, if it supports an operator:

   public class UnitTest1 {
      class MyStringable {
         public static implicit operator MyStringable(string value) {
            return new MyStringable();
         }
      }

      [TestMethod]
      public void MyTestMethod() {
         MyStringable foo = "abc";
      }
   }

---

Edit To be more clear: As you asked, if string will be converted into any constructor call, let's have a look into the IL code.

Taken this test method:

   [TestClass]
   class MyClass {
      [TestMethod]
      public void MyTest() {
         string myString = "foo";
         if (myString == "bar")
            Console.WriteLine("w00t");
      }
   }

Creates the following IL code:

.method public hidebysig instance void MyTest() cil managed
{
    .custom instance void [Microsoft.VisualStudio.QualityTools.UnitTestFramework]Microsoft.VisualStudio.TestTools.UnitTesting.TestMethodAttribute::.ctor()
    .maxstack 2
    .locals init (
        [0] string myString,
        [1] bool CS$4$0000)
    L_0000: nop 
    L_0001: ldstr "foo"
    L_0006: stloc.0 
    L_0007: ldloc.0 
    L_0008: ldstr "bar"
    L_000d: call bool [mscorlib]System.String::op_Equality(string, string)
    L_0012: ldc.i4.0 
    L_0013: ceq 
    L_0015: stloc.1 
    L_0016: ldloc.1 
    L_0017: brtrue.s L_0024
    L_0019: ldstr "w00t"
    L_001e: call void [mscorlib]System.Console::WriteLine(string)
    L_0023: nop 
    L_0024: ret 
}

As you see, all string values (foo, bar and w00t) are still strings and do not call any hidden constructor.

Hope this is more explaining.