Well, I am not sure if I describe the problem clearly, currently I am using ExtJS to do some developing, I saw some objects are "singleton", such as "Ext.Viewport", In C++, I can get the address of the object to see if they are actually same object, in Python, I can use "id" function to get the hash code of the object, and In Java I have similar built-in function "hashCode" to check if the objects are really same object, is there similar ways in javascript for this? so if there are some functions or operator in javascript, then I can tell if the object in ExtJS defined as "singleton" is really referencing to the same object.
Well, I am not sure if I describe the problem clearly, currently I am using ExtJS to do some developing, I saw some objects are "singleton", such as "Ext.Viewport", In C++, I can get the address of the object to see if they are actually same object, in Python, I can use "id" function to get the hash code of the object, and In Java I have similar built-in function "hashCode" to check if the objects are really same object, is there similar ways in javascript for this? so if there are some functions or operator in javascript, then I can tell if the object in ExtJS defined as "singleton" is really referencing to the same object.
Share Improve this question edited May 11, 2015 at 12:56 python asked May 11, 2015 at 12:44 pythonpython 1,9404 gold badges24 silver badges35 bronze badges 1- You would need to iterate over the key/value pairs of each object that you're paring to work out if they're the same. – Andy Commented May 11, 2015 at 12:46
5 Answers
Reset to default 2You don't need anything so plicated. If two values are the same object, then they will be equal.
var foo = {};
var bar = foo;
alert(foo == bar);
If they are different (even if identical) objects, they won't be.
var foo = {};
var bar = {};
alert(foo == bar);
Your question is not very clear, but I'll try to answer.
Javascript itself does not use unique identifiers for each object by default. You could add this if you wanted to.
Depending on your requirements, you could also use the typeof operator to pare the type.
ExtJs however, does use unique id's (either id or itemId) and also allows you to get the class name of the object that your using. So you could do this easily in ExtJs.
The answer depends on whether you are paring the type of object, or the actual object instance itself.
This other SO answer may be beneficial
I think that I'm understanding you... but, did you check this JavaScript parator ?
=== - equal value and equal type
!== - not equal value or not equal type
reference: Javascript parators
If you want to know if two object references refer to the same single object instance, use ==.
If you want to do a deep parison of the referenced objects to see if the objects contain all the same values, even if they are not the same object instance, use Lodash's _.isEqual(a, b) method.
could also convert both to json, and use something like jsonDiff: https://github./pkafel/json-diff