آموزش جاوا اسکریپت Java Script قسمت دوازدهم

 var str = "Please locate where 'locate' occurs!";
var pos = str.indexOf("locate"); // return 7

 var str = "Please locate where 'locate' occurs!";
var pos = str.indexOf("locate", 8); // return 21

 var str = "Please locate where 'locate' occurs!";
var pos = str.lastIndexOf("locate"); // return 21

 var str = "Please locate where 'locate' occurs!";
var pos = str.lastIndexOf("locate", 20); // return 7

 var str = “This is test!”;
var subStr = str.slice(5, 7); // return is

 var subStr = str.slice(-8, -6); // return is

 var subStr = str.slice(5); // return is test!
var subStr = str.slice(-8); // return is test!

 var substr = str.substring(5, 7); // return is
var substr = str.substring(5); // return is test!

 var substr = str. substr(5, 2); // return is
var subStr = str.substr(-8, 2); // return is
var substr = str.substr(5); // return is test!
var substr = str.substr(-8); // return is test!

 var res = str.replace("test","apple");// return This is apple!

 var res = str.toUpperCase(); 

 var res = str.toLowerCase();

 var str1 = “Hello”;
var str2 = “World”;
var res = str1.concat(“ “, str2);

 str1.charAt(0);            // returns H

 str1.charCodeAt(0);            // returns 72

 var arr = str.split(“ “);

 var arr = str.split(“”);

 str[0]