How to determine whether an object is a jquery object?

Method to determine whether an object is a jquery object: use the instanceof operator, the syntax "if(object instanceof jQuery){//jQuery object}else{//other objects}", object is used to specify the need to judge Object.

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The operating environment of this tutorial: windows7 system, jquery3.5 version, This method works for all brands of computers.

Method to determine whether an object is a jquery object:

When writing a recursive function to input a JSON object, the JSON data includes jQuery objects, this is It resulted in too many loop errors. I searched online for a long time and found that there was none. I thought I could use instanceof Date to determine whether it is a date object. Why not give it a try? The results show that obj instanceof jQuery can determine whether an object is a jQuery object.

By the way, to determine the type of a JavaScript object, you can use typeof, but typeof can only determine the basic object of js (string, boolean, number, object, ect.). I don’t understand. Just google it. As for object objects, many objects in js are objects. For example, Date object is a kind of object. Fortunately, the sky is the limit, there is an instanceof that can determine whether it is a date or jquery type.

Let’s be more detailed. Date is actually an object, and so is jQuery. Then after you create a new Date, the object becomes an instance, so you have to use instanceof to determine the source of the instance.

var obj = $("body");
if(obj instanceof jQuery){
  alert("这是一个jQuery对象");
}else{
  alert("这是一个其它对象")
}

instanceof operator is used to detect whether the prototype attribute of the constructor appears on the prototype chain of an instance object

Note: When jquery objects are named, they usually start with $, such as var $ps = $ ('p'), the advantage of this is that you can know at a glance that $ps is a jquery object, and the readability of the program is greatly improved.

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