String :
>Anything written in quotes is String.
>You can use single or double quotes
>String is a primitive data type
Define String :
1st way -
let myName = "vinod thapa"
2nd way -
let ytName = new String("vinod thapa")
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length:
let myName = "vinod thapa";
console.log(myName.length);
Escape Character :
let myName = "vinod \"elli\" thapa";
console.log(myName);
Find a string in a string :
indexOf() and lastIndexOf() - if matched , return index position , else return -1
let myName
= "vintodthapa";
console.log(myName.indexOf("t"));
console.log(myName.indexOf("t",2));
console.log(myName.lastIndexOf("t"));
Searching for a string in a string :
search() -
>if matched , return index position , else return -1
let myName = "vintodthapa";
console.log(myName.search("t"));
>cannot take second start position
let myName = "vintodthapa";
console.log(myName.indexOf("t",5));
console.log(myName.search("t",5)); //cannot take second start position
Extraction String parts :
slice() -
>extract a part of a string and return the extracted part in a new string
>It takes 2 parameter (start position , end position(optional))
>Select starting element but doesn't add the last element
>Orignal string will not be muted
let myName = "vintodthapa";
console.log(myName.slice(0,4));
console.log(myName.slice(4));
console.log(myName.slice(4,-2));
substring() -
>similar to slice
>cannot use negative indexes
let myName = "vintodthapa";
console.log(myName.substring(0,4));
console.log(myName.substring(4));
console.log(myName.substring(4,-2));;
substr() :
let myName = "vintodthapa";
console.log(myName.substring(4,2));
console.log(myName.substr(4,2));
replace() :
> does not change the old string
> it only replaces the first match
let myName = "vinod thapa vinod";
console.log(myName.replace("vinod",'Vinod'))
Extracting string character :
charAt() :
>returns the character of the specified index number
let myName = "vainod thapa vinod";
console.log(myName.charAt(1))
charCodeAt():
always returns an UTF-16 integer i.e (0 to 65535)
UTF - unique number is provide to every character
let myName = "vainod thapa vinod";
console.log(myName.charAt(1))
console.log(myName.charCodeAt(1))
Q) Find unicode of last character ?
let myName = "vainod thapa vinod";
console.log(myName.charCodeAt(myName.length -1))
Property Access :
let myName = "vainod thapa vinod";
console.log(myName[1]);
Other useful methods :
toUpperCase() , toLowerCase() , concat() :
let myName1 = "himanshu";
let myName2= "Himanshu";
console.log(myName1.toUpperCase());
console.log(myName2.toLowerCase());
console.log(myName1.concat(myName2));
console.log(myName1.concat(" ",myName2)); //for space
trim() :
//remove white space from start and end
let myName1 = " himanshu ";
console.log(myName1.trim());
split() :
convert string to array :
let myName1 = "hi,ma,ns,hu";
console.log(myName1.split(","));
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