Using Object.prototype.toString in JavaScript to determine whether it is an array_javascript tips

Why use Object.prototype.toString instead of Function.prototype.toString or others? This is related to their toString interpretation method. The following is the explanation of Object.prototype.toString in ECMA:

Copy code The code is as follows:

Object.prototype.toString( )

When the toString method is called, the following steps are taken:
1. Get the [[Class]] property of this object.
2. Compute a string value by concatenating the three strings “[object “, Result (1), and “]”.
3. Return Result (2)

The process is simply as follows: 1. Get the class name (object type) of the object. 2. Then combine [object, obtained class name,] and return.
ECMA has the following description of Array:

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The [[Class]] property of the newly constructed object is set to “Array”.

So we use the following code to detect the array:

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function isArray(o) { return Object.prototype.toString.call(o) === '[object Array]'; }

This method not only solves the cross-page problem of instanceof, but also solves the problem of attribute detection method. It is really a coup and a good solution.
In addition, this solution can also be applied to determine objects of Date, Function and other types.

There are several other methods:

Copy code The code is as follows:

var arr = []; return arr instanceof Array;

If there are other good methods, please post them.