The right way to define a custom object properties?

Question

I am currently defining custom object properties as follows:

private int count;
public int Count
{
    get { return count; }
    set { Count = value; }
}

my fist part of the question is there any difference between defining fields like that and like:

private int count;
public int Count {get; set;}

unless you want to check something about the value as so:

private int count;
public int Count
{
    get { return count; }
    set
    {
        if (value >= 0)
        {
            count = value;;
        }
        else MessageBox.Show("Value is negative", "Error", MessageBoxButton.OK, MessageBoxImage.Error);
    }
}

And the second part is is there a better way of defining object properties in C#?

I'm voting to close this question as off-topic because all of this is explained in official documentation. Consult that first https://msdn.microsoft.com/en-us/library/x9fsa0sw.aspx — Jeroen Vannevel, Mar 23 '17 at 20:34

BradleyDotNET · Accepted Answer · 2017-03-23T21:13:39.080

2

In your first example you define a private field and a property to access it. In your second example you define a private field and an auto-property that has its own backing field. So yes, there is a difference.

Unless you need custom get/set logic as in your final example, I would use the auto-property. However you shouldn't have a separate backing field (since it is independent of the property) so your code would just be:

public int Count {get; set;}

In either case (full or auto); you are using the correct way of defining properties in C#. The only thing I would add is that if you have get only properties, you can use expression-bodied members in C#6+:

public string Title => "Title"; //basically public string Title {get;} = "Title";

This is can be more efficient then the similar property because it doesn't use a backing field.

edited Mar 23 '17 at 21:13

answered Mar 23 '17 at 20:28

BradleyDotNET

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Strictly speaking the expression-bodied property isn't exactly equivalent to `public string Title { get; } = "Title"`. The latter will result in a readonly backing field that will store the string `"Title"` while the former won't create a backing field. – Kyle Mar 23 '17 at 21:06
@Kyle Thanks, modified to reflect that. – BradleyDotNET Mar 23 '17 at 21:13

The right way to define a custom object properties?

1 Answers1