The Symbol.keyFor() is an inbuilt method in JavaScript that is used to retrieve the key which has been shared with the given symbols and this key is retrieved from the global symbol registry.
Syntax:
Symbol.keyFor(sym);
Here “Symbol” is the symbol that is to be searched into the runtime-wide symbol registry.
Parameters: This method accepts a parameter “sym” which is the symbol for which the key is to be found.
Return value: This method returns a string representing the key for the given symbol found in the global registry otherwise it returns undefined. JavaScript code to show the working of this method.
Example 1: In this example, we will use Symbol keyFor() Method.
javascript
// Some symbols are created // with proper key const sym1 = Symbol. for ( 'Geeks' ); const sym2 = Symbol. for (123); const sym3 = Symbol. for ( "gfg" ); const sym4 = Symbol. for ( '789' ); // Calling the keyFor() method and // getting the key for the above symbols console.log(Symbol.keyFor(sym1)); console.log(Symbol.keyFor(sym2)); console.log(Symbol.keyFor(sym3)); console.log(Symbol.keyFor(sym4)); |
Geeks 123 gfg 789
Example 2: In this example, we will use Symbol keyFor() Method.
javascript
// Creating some symbols without key const sym1 = Symbol. for (); const sym2 = Symbol.iterator; // Calling the keyFor() method and // getting the key for the above symbols console.log(Symbol.keyFor(sym1)); console.log(Symbol.keyFor(sym2)); |
undefined undefined
Supported Browsers:
- Google Chrome 40 and above
- Edge 12 and above
- Firefox 36 and above
- Opera 27 and above
- Safari 9 and above
Reference: https://devdocs.io/javascript/global_objects/symbol/keyfor