Useful String methods:
.charAt(0) : Returns the character at index 0.
.toUpperCase() & .toLowerCase() : Returns the case of the char.
.substring( start, end ) : This function gives the substring starting from start to end (exclusive). If the method called without y params, it will return upto end of the string.
.slice( start, end ) : slice extracts from start and up to but not including end. slice(1,4) extracts the elements indexed 1, 2, and 3. Both .substring() & .slice() do same thing except that .slice can calculate from backward also. If we give .slice( -4, 2) , then two char will be returned and the starting point will be 4th from backward.
.substr(): Does same job like slice.
var str = 'abcdefghij';
console.log('(1, 2): ' + str.substr(1, 2)); // '(1, 2): bc'
console.log('(-3, 2): ' + str.substr(-3, 2)); // '(-3, 2): hi'
console.log('(-3): ' + str.substr(-3)); // '(-3): hij'
console.log('(1): ' + str.substr(1)); // '(1): bcdefghij'
console.log('(-20, 2): ' + str.substr(-20, 2)); // '(-20, 2): ab'
console.log('(20, 2): ' + str.substr(20, 2)); // '(20, 2): '
using substr() to get the window location.
var url = "http://www.facebook.com/index.php";
info.innerHTML = url.substr( url.lastIndexOf("/") + 1 ); // index.php
.split( delimiter ) : Converts an string to an array based on given delimiter.
var info = document.getElementById("info");
var str = "this is a good day.";
// gettting char from a string by index
info.innerHTML = str.charAt(0); // t
// converting upper & lowercase
info.innerHTML = str.charAt(0).toUpperCase(); // T
info.innerHTML = str.charAt(0).toLowerCase(); // t
var str = 'sajib';
info.innerHTML = str.substring(2, 4); // ji. returned char at index 2, 3
info.innerHTML = str.substring(1); // ajib. returned char from index 1 to end of string
info.innerHTML = str.slice(2, 4); // ji. start from 4th char backward and then two char forward.
info.innerHTML = str.substr(-4, 2); // aj. start from 4th char backward and then two char forward.
var url = "http://www.facebook.com/index.php";
info.innerHTML = url.substr( url.lastIndexOf("/") + 1 ); // index.php
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