Underscore.js _.isMap() Function
Underscore.js is a library in javascript that makes operations on arrays, string, objects much easier and handy. _.isMap() function is used to check whether the given object is javascript Map or not.
Note: It is very necessary to link the underscore CDN before going and using underscore functions in the browser. When linking the underscore.js CDN The “_” is attached to the browser as a global variable.
Syntax:
_.isMap(object);
Parameters :
- object : It is any javascript object such as array, string, maps, set etc.
Returns : It returns the boolean value. If the object is a Map of javascript it returns true otherwise false is returned by the function.
Few Examples are given below for a better understanding of the function.
Example 1:
When an array is given the output is false.
<!DOCTYPE html>
< html lang = "en" >
< head >
< meta charMap = "UTF-8" >
< meta name = "viewport"
content = "width=device-width, initial-scale=1.0" >
< title >Document</ title >
< script src =
</ script >
</ head >
< body >
< script >
//creating a array of size 2 using constructor
var obj= new Array(2);
//filling array with value 10
obj.fill(10);
//using the underscore.js function _.isMap()
var isMap= _.isMap(obj);
console.log(isMap)
//If the given object is Map it prints the object is Map.
if(isMap)
console.log(`The ${obj} is the Map of Javascript.`)
else
console.log(`The ${obj} is not the Map of Javascript.`)
</ script >
</ body >
</ html >
|
Output:
Example 2:
When a Map is given it returns true.
<!DOCTYPE html>
< html lang = "en" >
< head >
< meta charMap = "UTF-8" >
< meta name = "viewport"
content = "width=device-width, initial-scale=1.0" >
< title >Document</ title >
< script src =
</ script >
</ head >
< body >
< script >
//creating a Map using constructor
var obj= new Map();
//using the underscore.js function _.isMap()
var isMap= _.isMap(obj);
console.log(isMap)
//If the given object is Map it prints the object is Map.
if(isMap)
console.log(`The ${obj} is the Map of Javascript.`)
else
console.log(`The ${obj} is not the Map of Javascript.`)
</ script >
</ body >
</ html >
|
Output:
Example 3:
When giving an object as a parameter the output is false
<!DOCTYPE html>
< html lang = "en" >
< head >
< meta charMap = "UTF-8" >
< meta name = "viewport"
content = "width=device-width, initial-scale=1.0" >
< title >Document</ title >
< script src =
</ script >
</ head >
< body >
< script >
//creating a Javascript Object using constructor
var obj= new Object();
obj={
"a":1,
"b":2
}
//using the underscore.js function _.isMap()
var isMap= _.isMap(obj);
console.log(isMap)
//If the given object is Map it prints the object is Map.
if(isMap)
console.log(`The ${obj} is the Map of Javascript.`)
else
console.log(`The ${obj} is not the Map of Javascript.`)
</ script >
</ body >
</ html >
|
Output:
Last Updated :
25 Nov, 2021
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