key exists javascript code example
Example 1: javascript does key exist
var person={"name":"Billy","age":20}
person.hasOwnProperty("name"); // true
person.hasOwnProperty("sex"); // false
Example 2: javascript hashtable contains key
if (obj.hasOwnProperty("key1")) {
...
}
Example 3: check if a key exists in an object javascript
"key" in obj // true, regardless of the actual value