How to copy an object in JS, such as a JS object as follows.
If you know that all the attributes of this object can be new again, and then assign a value to each attribute, you can do it, but what if you don't? How do I create an object with the same content?
Copy Code code as follows:
var obj={colkey: "Col", Colsinfo: "NameList"}
The simplest thing is to use for-in,
For example, OBJ2 has exactly the same attributes as obj
Copy Code code as follows:
var obj2=new Object ();
For (var p in obj)
{
Var name=p;//property Name
Value for Var value=obj[p];//property
OBJ2[NAME]=OBJ[P];
}
In fact, this way has a certain limit, the key is in the JS for a certain limit, and will not traverse all attributes of the object, will only traverse the enumerable properties, by the JS core defined methods are not enumerable, such as ToString (), However, the attributes defined in the code are enumerable (can be specifically defined as not enumerable). So this method is enough.
If an object can be used for in-exhaustive, we can judge by the propertyIsEnumerable attribute, as follows:
propertyIsEnumerable Property
Returns a Boolean value that indicates whether the specified property is part of an object and whether the property is enumerable.
Object.propertyisenumerable (Proname)
Parameters
Object
Required option. An object.
Proname
Required option. A string value for a property name.
Description
If proname exists in object and you can use a for ... The propertyIsEnumerable property returns True if the in loop is a poor lift. If object does not have the specified property or the specified property is not enumerable, then the propertyIsEnumerable property returns False. Typically, predefined properties are not enumerable, and user-defined attributes can always be enumerated.
The propertyIsEnumerable property does not consider objects in the prototype chain.
