In operator Usage Analysis in javascript, javascript Operator

In operator Usage Analysis in javascript, javascript Operator

This example describes the in operator usage in javascript. Share it with you for your reference. The specific analysis is as follows:

The in operator wants its left operand to be a string or can be converted to a string, and its right operand to be an object. If the right object has a property name named the left operation value, then the expression returns true:

Var point = {x: 1, y: 1 }; "x" in point // true "z" in point // false "toString" in point // truevar ary = [1, 2, 3]; "0" in ary; // true, ary contains index 0 ("0" is switched to 0); 1 in ary; // true, ary contains Index 13 in ary; // false

I hope this article will help you design javascript programs.