What is an elegant way to try catch properties in C#

Question

What's an elegant way to refactor this code?

Say, I have the following object

public class SomeObject
{
    public SomeInnerObject1 Cat { get; set; }
    public SomeInnerObject2 Dog { get; set; }

    public class SomeInnerObject1
    {
        public int Age { get; set; }

        public string AgeAsString
        {
            get
            {
                if(Age < 0 )
                    throw new Exception();

                return Age.ToString();
            }
        }
    }

    public class SomeInnerObject2
    {
        public string BirthDayString { get; set; }
        public DateTime BirthDay { get { return DateTime.Parse(BirthDayString); } }
    }
}

And say, I have to set a few textboxes's values that I need to set

var obj = new SomeObject
          {
              Cat = new SomeObject.SomeInnerObject1 {Age = -1},
              Dog = null
          };

//These will pass but it looks ugly
try
{
    textbox1.Text = obj.Dog.BirthDay.Month.ToString();
}
catch{ }

try
{
    textbox2.Text = obj.Cat.AgeAsString;
}
catch { }

//These will fail
textbox1.Text = obj.Dog.BirthDay.Month.ToString();
textbox2.Text = obj.Cat.AgeAsString;

Is there a better way to do this?

Thanks,

Chi

Answer 1

When I really don't care what happens for a particular line of code, I do something like this:

ExecuteIgnoringExceptions(() => textBox.Text = Some.Possibly.Bad.Value);

void ExecuteIgnoringExceptions(Action a) 
{
    try
    {
        a.Invoke();
    }
    catch
    {
    }
}

Answer 2

I would start by moving the Int check from the get to the set property. If it isn't supposed to be less than 0, then don't let it get set to less than 0. For the date, use a TryParse method in the setter to make it exception safe. Then make sure that use a private setter in the BirthDay property.

public class SomeObject
{
    public SomeInnerObject1 Cat { get; set; }
    public SomeInnerObject2 Dog { get; set; }

    public class SomeInnerObject1
    {
        private int _Int = 0;
        public int Int {
            get
            {
                return _Int;
            }
            set
            {
                if(value < 0) 
                    throw new Exception("Int must be greater than or equal to 0.");
                else
                    _Int = value;
            }
       }

        public string String
        {
            get
            {
                return Int.ToString();
            }
        }
    }

    public class SomeInnerObject2
    {
        private string _BirthDayString = "";
        public string BirthDayString
        {
            get
            {
                return _BirthDayString;
            }
            set
            {
                DateTime newDate;
                if(DateTime.TryParse(value, newDate))
                    BirthDay = newDate;
                else
                    throw new ArgumentException("Birthday string must be a properly formatted date.");
            }
        }

        private DateTime _BirthDay = DateTime.MinValue;
        public DateTime BirthDay
        {
            get 
            {
                return _BirthDay;
            }
            private set
            {
                _BirthDay = value;
            }
        }
    }
}

The main point being that values should be validated on the way in rather than on the way out.