Underscore.js is a JavaScript library that provides a lot of useful functions that help in the programming in a big way like the map, filter, invoke, etc even without using any built-in objects.
The _.uniqueId() function is an inbuilt function in Underscore.js library of JavaScript which is used to generate a globally unique id for the client-side models or the DOM elements which requires one. When a prefix is passed as an argument to this method, the id generated will be appended to it.
Syntax:
_.uniqueId( prefix )
Parameters: It accepts a single parameter as mentioned above and described below:
- prefix: It is the prefix that would be appended to the id It is am optional parameter.
Return Value: This method returns a globally unique id.
Example 1:
HTML
<!DOCTYPE html> < html > < head > < script src = </ script > </ head > < body > < script type = "text/javascript" > // Using _.uniqueId() method // with its parameter console.log(_.uniqueId('gfG_')); console.log(_.uniqueId('Geeks_')); console.log(_.uniqueId('CS_')); </ script > </ body > </ html > |
Output:
gfG_1 Geeks_2 CS_3
Example 2:
HTML
<!DOCTYPE html> < html > < head > < script src = </ script > </ head > < body > < script type = "text/javascript" > // Using a loop for (i = 3; i < 100 ; i *= 2) { // Calling uniqueId method // without any parameter console.log(_.uniqueId()); } </script> </ body > </ html > |
Output:
1 2 3 4 5 6