JavaScript ES5

JavaScript ES5


JavaScript ES5
ECMAScript 2009 is also known as ES5. It was the first major revision to JavaScript. 
 
ES5 Features
There are various features in ECMAScript 5 or ES5:
  • "use strict"
  • String[number] access
  • Multiline strings
  • String.trim()
  • Array.isArray()
  • Array forEach()
  • Array map()
  • Array filter()
  • Array reduce()
  • Array reduceRight()
  • Array every()
  • Array some()
  • Array indexOf()
  • Array lastIndexOf()
  • JSON.parse()
  • JSON.stringify()
  • Date.now()
  • Date toISOString()
  • Date toJSON()
  • Property getters and setters
  • Reserved words as property names
  • Object methods
  • Object defineProperty()
  • Function bind()
  • Trailing commas
String trim()
 
JavaScript String trim() method 
The trim() method removes the white spaces from the beginning and end of the string.
 
Example1 -
 
https://lh4.googleusercontent.com/Ca-5VStRfRP2oF3g4zPxkh4o-8B94AhMNKVqSDCHFkP3X7y-32aQR84lx263V8onFgSvW5nXcBLX0cZlJljoGV-z2tRZPzidJWzcBSwcURU3LXTZCazRJOlhyLQMuOe-SRh9TlE1
Output -
https://lh6.googleusercontent.com/SAb0GQ2ZxeKueIy-_p82pjdjbLMjbZujUSnJ6DJGCXMrF-biqDWcN2CSeRj7cGf8acKOSzh9KOnl5sY5TgsaRnKNycOs1wkA6bhXxM66CbtfN3q21pL_HtaDOPxnwEmyatti4otE
 
 trimStart() and trimLeft() method 
 
The trimStart() and trimLeft() method will remove the white spaces from the beginning of the strings.
 
Syntax
 
var result = string.trimStart();
 
Example 2 -
 
https://lh6.googleusercontent.com/3FXxSa_69wbosXTUZr6gA043Y4Hdoa0OnHPwQ_cVflbgbk0_BODBfFXsbCwUd6BoVJLRiOfibMmr1qJW2GKOaUvk2HiuSbgslravzFWRPDTaDJ2SYJU9VNNo3TojLseB5V1RspCb
 
Output -
 
https://lh6.googleusercontent.com/SAb0GQ2ZxeKueIy-_p82pjdjbLMjbZujUSnJ6DJGCXMrF-biqDWcN2CSeRj7cGf8acKOSzh9KOnl5sY5TgsaRnKNycOs1wkA6bhXxM66CbtfN3q21pL_HtaDOPxnwEmyatti4otE
Array foreach()
 
In this Tutorial you will learn about JavaScript array foreach() method, The foreach() calls a function for each in an array element.
 
The Syntax of foreach() method is as follows: 
 
arrayName.forEach(function((element) => ( /* ... */ ))
 
Example 1 -
 
https://lh5.googleusercontent.com/2ukjz2sqnof8dCSL5MHbQ3y4Me2T4AVvoHiATbpD-aXizXfTl2j3j8koveAT131_yVV_GiSMcHGIs3JXm2fDUIqFVupqo9RTHyUMQ08Lpvg_zc6M4scHcpBE0lJhScgavTQqGrgK
 
Output
 
https://lh4.googleusercontent.com/48TMdkcI5ZikMQEDp7sPC0ZDvc5IQ-fnlRz__hq9UlG6acKqqrhbkvKrtnQP2MpKXiZScIpRGAAi0mSkiM2DFEqQ8t3fQm5g_pNMjFx0cievWQLhXhRTSx1UDM8i_pLGz0-vD6X0
 
Example2
 
https://lh5.googleusercontent.com/2FN1RFBaXBePhzbACmxlCkne5q4YUOyG8VYqUqeZe4ysDvxq2d8OyQcph8DxLVohie7LuUhNN5EiagEWs-IA0E49DdirtkWT9gjDH_z9mHxqVxQxXOO9Y034slWygrXWVb7vtUQB
Output
 
https://lh4.googleusercontent.com/-RfnA0H7hGCU7dwFaw_cbKIfIeRJHeFTaC6i-ro5_gcXb5unRZOkYGXtCGYZJrUxJdwAANDQ63J73EHhpKgIdO83SnaU3AWGx-KAjQbB0rycoMoRcRi6bFSVr1VinlKxp_ZrrnIK
 
Array map()
 
The map() method creates a new array with the results of calling a provided function on each element in the calling array.
 
Syntax
var new_array =
current_array.map(function(currentItem, index, array)
{
      //Application Logic to current array items 
         //return items for new array
})
 
Example1-
 
https://lh6.googleusercontent.com/koOZHNu5iOXaqFdwojJDUIm7n8hhiFi95REbEtaOVlIGZIuJ9y5SGAxiRBaJnauNoP_X0QxBIAwaWtMOpetVCZA88T6t7QqtDBfUEEz96a-hMjdywjIqm4JdQEUgcNbTH2v9bXFo
 
Output
 
https://lh5.googleusercontent.com/Cx7Rq6LDb0RaRbEInQxMX2PzB8TEXj10kmCDqVyNxGVMBGv0wraJyiLgylsyTdfYItuzIgrvRNRhxs7twKL3fDVnt2zSrU1rJNjld9B_xZW3SgfNgLTtpxle4HnHCfcmOGyuHKIX
 
Example 2 - Mapping an array of numList to an array of square roots
 
https://lh5.googleusercontent.com/g3MSdoaVNDOA9xvcFF_sfPaFWLFIFwZw74q_aoxMNzi5grGVIj1xpO33M9mJX31sLDf7c10rDBRFRRZXekUKT9mrGpNa5lCwCdtHOr-aAcOgO1esX03UC2mLWyV-qdRghM9xb4lG
 
Output
 
https://lh6.googleusercontent.com/ALBaYFr9beH1EHPgUuhKnORfMXt4NJqwWYMWl5lnfCpT0ZUjSk9McsQtBjaVM9B9_DOIOJQuWVOW4J9ysm_Rroc-4Jf27z8FMCE_yWQqbQYMcpuBEiHOITTO0nM8bKnWoyYXeLSG
 

JavaScript Array Filter

Example1

 

Output

Example2

Output