WeakRefence's Target not cleaned

Question

I'm preparing for MS exam Programming in C# ExamRef 70-483 and reading book with the same name. There is chapter about using WeakReference and following example:

using System;
using System.Drawing;

class Program
{
    static WeakReference data;

    static void Main()
    {
        object result = GetData();
        GC.Collect();
        result = GetData();
    }

    private static object GetData()
    {
        if (data == null)
        {
            data = new WeakReference(LoadLargeData());
        }
        if (data.Target == null)
        {
            data.Target = LoadLargeData();
        }
        return data.Target;
    }

    private static object LoadLargeData()
    {
        return new Bitmap(20000, 20000);
    }
}

The only change I've done is LoadLargeData() implementation, in the book there is LoadLargeList() without implementation.

The problem is, that after invoking GC.Collect(), my data.Target is never null. How can I force GC to really collect this WeakReference data?

Compile application in release mode (with optimizations enabled), run without debugger attached (so add `Console.WriteLine("target is null")` in respective if branch to verify it's null). — Evk, Feb 20 '18 at 08:33

score 0 · Answer 1 · answered Feb 20 '18 at 08:37

0

As Evk mentioned in comment, running app in release mode without debugger attaches is the right answer, than garbage collection works as expected.

answered Feb 20 '18 at 08:37

Majak

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WeakRefence's Target not cleaned

1 Answers1