About C # static method invocation Issues

C # Code

public class TestClass
{
private static string Str = String. Empty;
Public TestClass ()
{
if (string. IsNullOrEmpty (STR))
{
STR = "Teststr";
}
}
public static string GetValue ()
{
return Str;
}
}

In the above code, STR is a need to be assigned at the time of program initialization according to the actual situation and stored in memory as a static property, so as to facilitate the operation of the program to take value

When the value is obtained by the Testclass.getvalue () method, the result is not "teststr", and the debug trace finds that the public TestClass () is not executed at all, and the reason is not well understood here.

About C # static method invocation Issues