Use variables to dynamically set js property names

Target :js property names can use variables

Example: the js object object, when assigned to the object property can be used in the following way

var object; 

object.prop1 = "value1";

object.prop2 = "value2"; 

The following can also be used:

object.push({prop1:"value1"});

object.push({prop2:"value2"}); 

Prop1 can be used as the property name here, either directly or in quotes, for example:

object.push({"<span style="font-family: Arial, Helvetica, sans-serif;">prop1</span>":"value1"}); 

The meaning is the same, that is,prop1 can only be recognized as a constant, even if it is a variable. For example:

var prop1 = "prop2"; 

object.push({prop1:"<span style="font-family: Arial, Helvetica, sans-serif;">value1</span>"}); 

What happens when you access prop2 through object ? Such as:

alert(<span style="font-family: Arial, Helvetica, sans-serif;">object.prop2) </span> 

Don't ask, undefined, of course, and access object.prop1 is "value1"

The reason for this is that attributes are treated as constants with or without quotation marks.

var arr=[]; 

arr['js']='jquery'; 

arr['css']='oocss'; 

var obj={}; 

for(var i in arr) 

{
obj.i=arr[i]; 

} 

alert(obj.js); 

The reader does not want to guess what alert prints ?

Of course is undefined.

Again, guess what alert(obj. I) will print if it's alert(obj. I) ?

Oocss, of course, why ? Because obj now has only one attribute I, and through two loops, the one in front of obj. I is overwritten by the one behind.