Horje
Javascript key exists Code Example
Javascript key exists 
var person={"name":"Billy","age":20}
person.hasOwnProperty("name"); // true
person.hasOwnProperty("sex"); // false
javascript hashtable contains key 
if (obj.hasOwnProperty("key1")) {
  ...
}
Source: stackoverflow.com
javascript check if key exists in object 
"key" in obj // true, regardless of the actual value

If you want to check if a key doesn't exist, remember to use parenthesis:
!("key" in obj) // true if "key" doesn't exist in object
!"key" in obj   // ERROR!  Equivalent to "false in obj"

Or, if you want to particularly test for properties of the object instance (and not inherited properties), use hasOwnProperty:
obj.hasOwnProperty("key") // true
Source: stackoverflow.com
check if a key exists in an object javascript 
"key" in obj // true, regardless of the actual value
Source: stackoverflow.com
how to check if a key exists in an object javascript 
!("key" in obj) // true if "key" doesn't exist in object
!"key" in obj   // ERROR!  Equivalent to "false in obj"
Source: stackoverflow.com
js check if object key exists 
var obj = { key: undefined };
obj["key"] !== undefined // false, but the key exists!
Source: stackoverflow.com



Javascript

Related
set value in span using jquery Code Example set value in span using jquery Code Example
jquery disable select Code Example jquery disable select Code Example
document on click dynamic element Code Example document on click dynamic element Code Example
breakline in react native Code Example breakline in react native Code Example
jquery extract number from string Code Example jquery extract number from string Code Example

Type:
 Code Example
Category:
 Coding
Sub Category:
 Code Example
Uploaded by:
 Admin
Views:
 7



 

Horje