How do I know the default value is used?

Question

Consider a method like this:

public void WorkAt(string location = @"home") {     //... } 

It can be called by passing a value explicitly, like:

WorkAt(@"company"); WorkAt(@"home"); 

Or just use the default value, like:

WorkAt(); 

Is there a way to know whether the default value is used?

For example, I want to code like this:

public void WorkAt(string location = @"home") {      if ( /* the default value is used unexplicitly */)      {          // Do something      }      else      {          // Do another thing      } } 

Be careful that WorkAt("home") is different from WorkAt() in this context.

Answer 1

There is not, and should not be, any reason to do this. The default value is there to do just that - provide a default value when none is specified.

If you need to perform a different function based on what is passed, I suggest overloading the method. For example:

public void WorkAt() {     //do something }  public void WorkAt(string location) {     //do other thing } 

Alternatively, if there is shared logic, you could use an additional parameter:

public void WorkAt(string location = "home", bool doOtherThingInstead = false) {     if (!doOtherThingInstead)     {         //do something     }     else     {         //do other thing     }      //do some shared logic for location, regardless of doOtherThingInstead } 

As a side note, perhaps the example in the question was contrived, but WorkAt() with no parameter specified makes no lexical sense. One would expect a value after the word at. Perhaps you may want to rename the second method WorkAtDefaultLocation().

Answer 2

Your answer might be something like the following code.

public void CommonOperations(/*Some parameteres as needed.*/) {     // Shared operations between two methods. } public void WorkAt() {     string location = "home";     CommonOperations(/*Some parameteres as needed.*/);     //do something }  public void WorkAt(string location) {     CommonOperations(/*Some parameteres as needed.*/);     //do the other thing } 

I hope it will help.