C# Class Property Getter Invoked Automatically

Question

I have 2 class properties defined like so:

    private static string _validationError;
    public static string ValidationError
    {
        get {
            var temp = _validationError;
            _validationError = "abc";
            return temp;
        }

        set { _validationError = value; }
    }

    public static string CurrentError { get; set; }

A method:

    public static bool IsErrorStringEmpty()
    {
        Console.WriteLine("dddd");

        return false;
    }

Test Method:

    [TestMethod]
    public void ValidationErrorTest()
    {
        CurrentError = "My Error";

        var empty = IsErrorStringEmpty();
    }

When I debug this test, this is the behavior I'm seeing:

1. Before the 2nd line of the test method is hit, ValidationError = null (Expected).

   

2. When it enters IsErrorStringEmpty(), before the 1st line is hit, ValidationError = null (Expected).

   

3. Then, right when it's hitting the 1st line, ValidationError = "abc". I don't know how this getter is being invoked at all even though I have no explicit code up to this point to access the ValidationError property.

   

I have breakpoint in the getter, but it didn't get hit, and the Call Stack is shown as below.

I'm sure it's somewhere but I can't seem to find it. Any pointers are greatly appreciated!

Answer 1

You're invoking the getter in the debugger. When code is executed in the evaluation of a property for display in a watch window it is really being executed, with real side effects.

Try watching _validationError instead.

Side effects in a getter can throw you for a loop. Best to avoid them.