Question

In my base class, the one that the others inherit from, has these properties:

private int DEFAULT_DISPLAY_ORDER = 999999;
private DateTime DEFAULT_DT = new DateTime(1111,1,1);

public int? Id {
    get 
    { 
        return Id.GetValueOrDefault(0);  
    }
    set 
    {
        if (DisplayOrder == null) DisplayOrder = DEFAULT_DISPLAY_ORDER;
        Id = value;
    }
}
public String Description { get; set; }
public int? DisplayOrder { get; set; }

But when I execute it, I get this error:

+ $exception {
     Cannot evaluate expression because the current thread is in a stack 
     overflow state.}
     System.Exception {System.StackOverflowException}

on line

if (DisplayOrder == null) DisplayOrder = DEFAULT_DISPLAY_ORDER;

What the heck is going on here?

Answer 1

Look at this:

public int? Id {
    get 
    { 
        return Id.GetValueOrDefault(0);  
    }

Here, accessing Id requires that you first fetch… Id. Bang.

Next:

set 
{
    if (DisplayOrder == null) DisplayOrder = DEFAULT_DISPLAY_ORDER;
    Id = value;
}

Look at the second part. In order to set Id, you have to… call the setter for Id. Bang.

You need a field for this:

private int? id;

// Now use the field in the property bodies
public int? Id {
    get 
    { 
        return id.GetValueOrDefault(0);  
    }
    set 
    {
        if (DisplayOrder == null) DisplayOrder = DEFAULT_DISPLAY_ORDER;
        id = value;
    }
}