Overloading Equals NullReferenceException

onez

Values is a indexer class with a Int64 array. If I try to check if a value class is null it results in a null reference exception. Checks for null inside this method result in an infinite loop. How should I determine if a Values class is null? public static bool operator ==(Values vals1, Values vals2) { bool ret = false; for (int x = 0; x < vals1.Length; x++) { if (vals1[x] == vals2[x]) ret = true; else return false; } return ret; }

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shimtanny21y ago
Hi You're right. I see the problem. I suggest to NOT overload the == and != operators. Leave them, they test the reference equality. Override the Equals (and also GetHashCode) method. public override bool Equals(object obj) { Value v = (Value) obj; if (this.Length == v.Length) { for (int i = 0; i < this.Length; i++) { if (this[i] != v[i]) { return false; } } return true; } return false; } public override int GetHashCode() { return base.GetHashCode (); } Cheers Simon
onez21y ago
I have to also overload the not equal operator. I had tried what you put and it causes an infinite loop. VS also suggest something about overloading the Equals object method?? public static bool operator !=(Values vals1, Values vals2) { return !(vals1 == vals2); }
shimtanny21y ago
Hi public static bool operator ==(Values vals1, Values vals2) { bool ret = false; if (vals1 != null & vals2 != null) { for (int x = 0; x < vals1.Length; x++) { if (vals1[x] == vals2[x]) ret = true; else return false; } } return ret; } What are you doing, if the Values have different length? Cheers Simon