This references my last question which appears to have been abandoned. I am experiencing an odd "bug" if you will with C# and MS VS 2015. To reproduce the error, follow the steps:
- Open console app project and copy paste code below.
- Set a break point here:
- First run code past break point, it works! :D
- Then run code again but this time STOP at the break point and DRAG the executing statement cursor INTO the if statement from here:
to here: 
Hit Continue and an NRE exception is thrown. Why does this happen? Is it just me? What is the technical explination for this?
CODE:
using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace testapp { class Program { static void Main(string[] args) { FILECollection randomCollection = new FILECollection(); // Fill with junk test data: for(int i = 0; i<10; i++) { FILE junkfile = new FILE() { fileName = i.ToString(), folderName = i.ToString(), fileHashDigest = new byte[1] }; randomCollection.Add(junkfile); } if (true) { Console.WriteLine("testing this weird exception issue..."); FILE test; test = new FILE(); test.fileName = "3"; test.folderName = "3"; test.fileHashDigest = new byte[1]; FILE exists = randomCollection.Where(f => f.fileName == test.fileName && f.fileHashDigest.SequenceEqual(test.fileHashDigest)).First(); } } } public class FILE { public FILE() { _fileName = "";} private string _fileName; public string fileName { get { if (false) return this._fileName.ToUpper(); else return this._fileName; } set { if (false) this._fileName = value.ToUpper(); else this._fileName = value; } } public string folderName { get; set; } public byte[] fileHashDigest { get; set; } } public class FILECollection : IEnumerable<FILE>, ICollection<FILE> { private HashSet<FILE> svgHash; private static List<FILE> PreallocationList; public string FileName = "N/A"; /// <summary> /// Default Constructor, will not /// preallocate memory. /// </summary> /// <param name="PreallocationSize"></param> public FILECollection() { this.svgHash = new HashSet<FILE>(); this.svgHash.Clear(); } /// <summary> /// Overload Constructor Preallocates /// memory to be used for the new /// FILE Collection. /// </summary> public FILECollection(int PreallocationSize, string fileName = "N/A", int fileHashDigestSize = 32) { FileName = fileName; PreallocationList = new List<FILE>(PreallocationSize); for (int i = 0; i <= PreallocationSize; i++) { byte[] buffer = new byte[fileHashDigestSize]; FILE preallocationSVG = new FILE() { fileName = "", folderName = "", fileHashDigest = buffer }; PreallocationList.Add(preallocationSVG); } this.svgHash = new HashSet<FILE>(PreallocationList); this.svgHash.Clear(); // Capacity remains unchanged until a call to TrimExcess is made. } /// <summary> /// Add an FILE file to /// the FILE Collection. /// </summary> /// <param name="svg"></param> public void Add(FILE svg) { this.svgHash.Add(svg); } /// <summary> /// Removes all elements /// from the FILE Collection /// </summary> public void Clear() { svgHash.Clear(); } /// <summary> /// Determine if the FILE collection /// contains the EXACT FILE file, folder, /// and byte[] sequence. This guarantees /// that the collection contains the EXACT /// file you are looking for. /// </summary> /// <param name="item"></param> /// <returns></returns> public bool Contains(FILE item) { return svgHash.Any(f => f.fileHashDigest.SequenceEqual(item.fileHashDigest) && f.fileName == item.fileName && f.folderName == item.folderName); } /// <summary> /// Determine if the FILE collection /// contains the same file and folder name, /// byte[] sequence is not compared. The file and folder /// name may be the same but this does not guarantee the /// file contents are exactly the same. Use Contains() instead. /// </summary> /// <param name="item"></param> /// <returns></returns> public bool ContainsPartially(FILE item) { return svgHash.Any(f => f.fileName == item.fileName && f.folderName == item.folderName); } /// <summary> /// Returns the total number /// of FILE files in the Collection. /// </summary> public int Count { get { return svgHash.Count(); } } public bool IsReadOnly { get { return true; } } public void CopyTo(FILE[] array, int arrayIndex) { svgHash.CopyTo(array, arrayIndex); } public bool Remove(FILE item) { return svgHash.Remove(item); } public IEnumerator<FILE> GetEnumerator() { return svgHash.GetEnumerator(); } IEnumerator IEnumerable.GetEnumerator() { return svgHash.GetEnumerator(); } } } I think either I am debugging in a terribly wrong way, or Microsoft should take a look at this. It's like future code is breaking current code...which is impossible!
