两个javascript对象如何在同一时间相等且不相等？

Question

Below is an example comparing two JavaScript objects but I am confused by the returned values.

var i=new Object()
var j=new Object()

i==j false

i!=j true

i>=j true

i<=j true

i>j false

i<j false

How are the values determined for the above? I am having trouble understanding.

Answer 1

Here are the reasons,

i==j false //Since both are referring two different objects

i!=j True  //Since both are referring two different objects

i>=j true  //For this, the both objects will be converted to primitive first,
           //so i.ToPrimitive() >= j.ToPrimitive() which will be 
           //evaluated to "[object Object]" >= "[object Object]" 
           //That is why result here is true.

i<=j true  //Similar to >= case

i>j false  //Similar to >= case

i<j false  //Similar to >= case

i<-j false //similar to >= case but before comparing "[object object]" will be negated 
           //and will become NaN. Comparing anything with NaN will be false 
           //as per the abstract equality comparison algorithm 

You mentioned i<-j will be evaluated to true . But that is wrong, it will be evaluated to false . See the reasons above.

Answer 2

Because each time you create an object and assign it to a variable, the variable really has a reference to the new object. The references are not the same so they are not equal. You can see this by doing this:

var a = {};
var b = a;

a == b

Not very enlightening but if you think references, it all makes sense.