LearnJavaScript/variable.js at master · alnumanqa/LearnJavaScript · GitHub

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//String, int,byte,short,long,char,float,boolean


//There are 3 types variable in javaScript
// let, var, const


console.log("-----------use of var-------------")

//we can reassign and redeclare value with var
varfirstName="Sakib";
varage=35;
vargrade=3.5;
varusCitizen=false;
varsex='M';
//check the type of variable
console.log(typeof(age));
console.log(typeof(usCitizen));
//redeclare variable with var
varfirstName="Tamim";
console.log(firstName)

//reassign the value with var
grade=3.1;
console.log(grade)


console.log("-----------use of let-------------")
// we can't redeclare but we can reassign the value with let
letfirstName1="Tamim";
//let name = "Iqubal";
//undefined value
letlastName="";
letage1=35;
letgrade1=3.5;
letusCitizen1='';
letsex1='M';

console.log(firstName1)
console.log(lastnName)
console.log(usCitizen1)


//we can't redeclare variable with let
//let firstName = "Afif";

//reassign the value with let
firstName1="Musfiq";
console.log(firstName1);

console.log("-----------use of const-------------")
//we can't neither redeclare or reassign const variable
constfirstName2="Sakib";
constage2=35;
constgrade2=3.5;
constusCitizen2=false;
constsex2='M';

console.log(age2)

/*
we can't reassign value with const variable
firstName2 = "Shoan";
console.log(firstName2);
*/

/*
we can't redeclare value with const
const firstName2 = "Afif";
*/