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Why are two empty lists not equal?

I thought that calling Equals () on two empty lists would return true, but that is not the case. Can someone explain why?

var lst = new List<Whatever>();
var lst2 = new List<Whatever>();
if(!lst.Equals(lst2))
    throw new Exception("seriously?"); // always thrown
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11 answers

Equals This compares the link of the two lists, which will be different because they are separate lists and that in this case it will always be false.

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Because it Equalschecks links - lstand lst2- different objects. (note that Equals is inherited from Objectand not implemented in List<T>)

Linq SequenceEquals.
SequenceEquals , Whatever ( ). , .

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List<T>.Equals() true, . , List<T>.SequenceEquals()

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int a = 10;
int b = 10;

if( a == b ) 
{
    // this will fire
}

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int c = a;
c = c+5;

if( a == c ) 
{
    // this won't, because a==10 and c==15
}

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var a = new List<Whatever>();
var b = new List<Whatever>();
if( a == b ) 
{
    // this won't fire, a and be are separate objects
}

var c = a;
c.Add(new Whatever());
if( a == c ) 
{
    // this will, a and c are the same object.
    a[0]; // holds the value added to c
}

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You do not need to program well to understand this;) Suppose you have this and that , its not important what is inside this and that . It is simply important that this one is not , which or which is not this . This is what you check there withequals

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