What is the difference between String.Empty and “” (empty string)?

Question

In .NET, what is the difference between String.Empty and \"\", and are they interchangable, or is there some underlying reference or Localization i

Answer 1

Another difference is that String.Empty generates larger CIL code. While the code for referencing "" and String.Empty is the same length, the compiler doesn't optimize string concatenation (see Eric Lippert's blog post) for String.Empty arguments. The following equivalent functions

string foo()
{
    return "foo" + "";
}
string bar()
{
    return "bar" + string.Empty;
}

generate this IL

.method private hidebysig instance string foo() cil managed
{
    .maxstack 8
    L_0000: ldstr "foo"
    L_0005: ret 
}
.method private hidebysig instance string bar() cil managed
{
    .maxstack 8
    L_0000: ldstr "bar"
    L_0005: ldsfld string [mscorlib]System.String::Empty
    L_000a: call string [mscorlib]System.String::Concat(string, string)
    L_000f: ret 
}