JavaScript-Interview-Questions/datatypes.html at master · FADL285/JavaScript-Interview-Questions · GitHub

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<!DOCTYPE html>
<html>
<head>
<title>DataTypes in JS</title>
</head>
<script>
/**
 * Six data types that are primitives:
 * Boolean
 * Null
 * Undefined
 * Number
 * String
 * Symbol (new in ECMAScript 6):- “Symbol” value represents a unique identifier.
 * and Object
 *
 **/
// ---------------
// Dynamic typing
// ---------------
varval=10;console.log("type of val: "+typeof(val));// Number
val=10.20;console.log("type of val: "+typeof(val));// Number
val='Hello World';console.log("type of val: "+typeof(val));// String
val=true;console.log("type of val: "+typeof(val));// Boolean
val=null;console.log("type of val: "+typeof(val));// Object
val=undefined;console.log("type of val: "+typeof(val));// Undefined


varobj=newObject();console.log("type of obj: "+typeof(obj));// Undefined
varn;console.log("type of n: "+typeof(n));// null datatype

console.log("type of x: "+typeof(x));// null datatype

// --------------
// let vs var
// --------------

functionvarTest(){
varx=1;
if(true){
varx=2;// same variable!
console.log("var: Inside value of x: "+x);// 2
}
console.log("var: Outside value of x: "+x);// 2
}
varTest();


functionletTest(){
letx=1;
if(true){
letx=2;// different variable
console.log("let: Inside value of x: "+x);// 2
}
console.log("let: Outside value of x: "+x);// 1
}
letTest();

// ----------
// Symbols
// ----------

// id is a new symbol
letid=Symbol();console.log("Type of id: "+typeof(id));

// id is a symbol with the description "id"
letid1=Symbol("id");
letid2=Symbol("id");

console.log("Is id1 == id2: "+(id1==id2));
</script>
<body>
 DataTypes in JavaScript
</body>
</html>
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<!DOCTYPE html>
<html>
<head>
<title>DataTypes in JS</title>
</head>
<script>
/**
 * Six data types that are primitives:
 * Boolean
 * Null
 * Undefined
 * Number
 * String
 * Symbol (new in ECMAScript 6):- “Symbol” value represents a unique identifier.
 * and Object
 *
 **/
// ---------------
// Dynamic typing
// ---------------
varval=10;console.log("type of val: "+typeof(val));// Number
val=10.20;console.log("type of val: "+typeof(val));// Number
val='Hello World';console.log("type of val: "+typeof(val));// String
val=true;console.log("type of val: "+typeof(val));// Boolean
val=null;console.log("type of val: "+typeof(val));// Object
val=undefined;console.log("type of val: "+typeof(val));// Undefined


varobj=newObject();console.log("type of obj: "+typeof(obj));// Undefined
varn;console.log("type of n: "+typeof(n));// null datatype

console.log("type of x: "+typeof(x));// null datatype

// --------------
// let vs var
// --------------

functionvarTest(){
varx=1;
if(true){
varx=2;// same variable!
console.log("var: Inside value of x: "+x);// 2
}
console.log("var: Outside value of x: "+x);// 2
}
varTest();


functionletTest(){
letx=1;
if(true){
letx=2;// different variable
console.log("let: Inside value of x: "+x);// 2
}
console.log("let: Outside value of x: "+x);// 1
}
letTest();

// ----------
// Symbols
// ----------

// id is a new symbol
letid=Symbol();console.log("Type of id: "+typeof(id));

// id is a symbol with the description "id"
letid1=Symbol("id");
letid2=Symbol("id");

console.log("Is id1 == id2: "+(id1==id2));
</script>
<body>
 DataTypes in JavaScript
</body>
</html>
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<!DOCTYPE html>
<html>
<head>
<title>DataTypes in JS</title>
</head>
<script>
/**
 * Six data types that are primitives:
 * Boolean
 * Null
 * Undefined
 * Number
 * String
 * Symbol (new in ECMAScript 6):- “Symbol” value represents a unique identifier.
 * and Object
 *
 **/
// ---------------
// Dynamic typing
// ---------------
varval=10;console.log("type of val: "+typeof(val));// Number
val=10.20;console.log("type of val: "+typeof(val));// Number
val='Hello World';console.log("type of val: "+typeof(val));// String
val=true;console.log("type of val: "+typeof(val));// Boolean
val=null;console.log("type of val: "+typeof(val));// Object
val=undefined;console.log("type of val: "+typeof(val));// Undefined


varobj=newObject();console.log("type of obj: "+typeof(obj));// Undefined
varn;console.log("type of n: "+typeof(n));// null datatype

console.log("type of x: "+typeof(x));// null datatype

// --------------
// let vs var
// --------------

functionvarTest(){
varx=1;
if(true){
varx=2;// same variable!
console.log("var: Inside value of x: "+x);// 2
}
console.log("var: Outside value of x: "+x);// 2
}
varTest();


functionletTest(){
letx=1;
if(true){
letx=2;// different variable
console.log("let: Inside value of x: "+x);// 2
}
console.log("let: Outside value of x: "+x);// 1
}
letTest();

// ----------
// Symbols
// ----------

// id is a new symbol
letid=Symbol();console.log("Type of id: "+typeof(id));

// id is a symbol with the description "id"
letid1=Symbol("id");
letid2=Symbol("id");

console.log("Is id1 == id2: "+(id1==id2));
</script>
<body>
 DataTypes in JavaScript
</body>
</html>
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<!DOCTYPE html>
<html>
<head>
<title>DataTypes in JS</title>
</head>
<script>
/**
 * Six data types that are primitives:
 * Boolean
 * Null
 * Undefined
 * Number
 * String
 * Symbol (new in ECMAScript 6):- “Symbol” value represents a unique identifier.
 * and Object
 *
 **/
// ---------------
// Dynamic typing
// ---------------
varval=10;console.log("type of val: "+typeof(val));// Number
val=10.20;console.log("type of val: "+typeof(val));// Number
val='Hello World';console.log("type of val: "+typeof(val));// String
val=true;console.log("type of val: "+typeof(val));// Boolean
val=null;console.log("type of val: "+typeof(val));// Object
val=undefined;console.log("type of val: "+typeof(val));// Undefined


varobj=newObject();console.log("type of obj: "+typeof(obj));// Undefined
varn;console.log("type of n: "+typeof(n));// null datatype

console.log("type of x: "+typeof(x));// null datatype

// --------------
// let vs var
// --------------

functionvarTest(){
varx=1;
if(true){
varx=2;// same variable!
console.log("var: Inside value of x: "+x);// 2
}
console.log("var: Outside value of x: "+x);// 2
}
varTest();


functionletTest(){
letx=1;
if(true){
letx=2;// different variable
console.log("let: Inside value of x: "+x);// 2
}
console.log("let: Outside value of x: "+x);// 1
}
letTest();

// ----------
// Symbols
// ----------

// id is a new symbol
letid=Symbol();console.log("Type of id: "+typeof(id));

// id is a symbol with the description "id"
letid1=Symbol("id");
letid2=Symbol("id");

console.log("Is id1 == id2: "+(id1==id2));
</script>
<body>
 DataTypes in JavaScript
</body>
</html>
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<!DOCTYPE html>
<html>
<head>
<title>DataTypes in JS</title>
</head>
<script>
/**
 * Six data types that are primitives:
 * Boolean
 * Null
 * Undefined
 * Number
 * String
 * Symbol (new in ECMAScript 6):- “Symbol” value represents a unique identifier.
 * and Object
 *
 **/
// ---------------
// Dynamic typing
// ---------------
varval=10;console.log("type of val: "+typeof(val));// Number
val=10.20;console.log("type of val: "+typeof(val));// Number
val='Hello World';console.log("type of val: "+typeof(val));// String
val=true;console.log("type of val: "+typeof(val));// Boolean
val=null;console.log("type of val: "+typeof(val));// Object
val=undefined;console.log("type of val: "+typeof(val));// Undefined


varobj=newObject();console.log("type of obj: "+typeof(obj));// Undefined
varn;console.log("type of n: "+typeof(n));// null datatype

console.log("type of x: "+typeof(x));// null datatype

// --------------
// let vs var
// --------------

functionvarTest(){
varx=1;
if(true){
varx=2;// same variable!
console.log("var: Inside value of x: "+x);// 2
}
console.log("var: Outside value of x: "+x);// 2
}
varTest();


functionletTest(){
letx=1;
if(true){
letx=2;// different variable
console.log("let: Inside value of x: "+x);// 2
}
console.log("let: Outside value of x: "+x);// 1
}
letTest();

// ----------
// Symbols
// ----------

// id is a new symbol
letid=Symbol();console.log("Type of id: "+typeof(id));

// id is a symbol with the description "id"
letid1=Symbol("id");
letid2=Symbol("id");

console.log("Is id1 == id2: "+(id1==id2));
</script>
<body>
 DataTypes in JavaScript
</body>
</html>
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<!DOCTYPE html>
<html>
<head>
<title>DataTypes in JS</title>
</head>
<script>
/**
 * Six data types that are primitives:
 * Boolean
 * Null
 * Undefined
 * Number
 * String
 * Symbol (new in ECMAScript 6):- “Symbol” value represents a unique identifier.
 * and Object
 *
 **/
// ---------------
// Dynamic typing
// ---------------
varval=10;console.log("type of val: "+typeof(val));// Number
val=10.20;console.log("type of val: "+typeof(val));// Number
val='Hello World';console.log("type of val: "+typeof(val));// String
val=true;console.log("type of val: "+typeof(val));// Boolean
val=null;console.log("type of val: "+typeof(val));// Object
val=undefined;console.log("type of val: "+typeof(val));// Undefined


varobj=newObject();console.log("type of obj: "+typeof(obj));// Undefined
varn;console.log("type of n: "+typeof(n));// null datatype

console.log("type of x: "+typeof(x));// null datatype

// --------------
// let vs var
// --------------

functionvarTest(){
varx=1;
if(true){
varx=2;// same variable!
console.log("var: Inside value of x: "+x);// 2
}
console.log("var: Outside value of x: "+x);// 2
}
varTest();


functionletTest(){
letx=1;
if(true){
letx=2;// different variable
console.log("let: Inside value of x: "+x);// 2
}
console.log("let: Outside value of x: "+x);// 1
}
letTest();

// ----------
// Symbols
// ----------

// id is a new symbol
letid=Symbol();console.log("Type of id: "+typeof(id));

// id is a symbol with the description "id"
letid1=Symbol("id");
letid2=Symbol("id");

console.log("Is id1 == id2: "+(id1==id2));
</script>
<body>
 DataTypes in JavaScript
</body>
</html>
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<!DOCTYPE html>
<html>
<head>
<title>DataTypes in JS</title>
</head>
<script>
/**
 * Six data types that are primitives:
 * Boolean
 * Null
 * Undefined
 * Number
 * String
 * Symbol (new in ECMAScript 6):- “Symbol” value represents a unique identifier.
 * and Object
 *
 **/
// ---------------
// Dynamic typing
// ---------------
varval=10;console.log("type of val: "+typeof(val));// Number
val=10.20;console.log("type of val: "+typeof(val));// Number
val='Hello World';console.log("type of val: "+typeof(val));// String
val=true;console.log("type of val: "+typeof(val));// Boolean
val=null;console.log("type of val: "+typeof(val));// Object
val=undefined;console.log("type of val: "+typeof(val));// Undefined


varobj=newObject();console.log("type of obj: "+typeof(obj));// Undefined
varn;console.log("type of n: "+typeof(n));// null datatype

console.log("type of x: "+typeof(x));// null datatype

// --------------
// let vs var
// --------------

functionvarTest(){
varx=1;
if(true){
varx=2;// same variable!
console.log("var: Inside value of x: "+x);// 2
}
console.log("var: Outside value of x: "+x);// 2
}
varTest();


functionletTest(){
letx=1;
if(true){
letx=2;// different variable
console.log("let: Inside value of x: "+x);// 2
}
console.log("let: Outside value of x: "+x);// 1
}
letTest();

// ----------
// Symbols
// ----------

// id is a new symbol
letid=Symbol();console.log("Type of id: "+typeof(id));

// id is a symbol with the description "id"
letid1=Symbol("id");
letid2=Symbol("id");

console.log("Is id1 == id2: "+(id1==id2));
</script>
<body>
 DataTypes in JavaScript
</body>
</html>
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<!DOCTYPE html>
<html>
<head>
<title>DataTypes in JS</title>
</head>
<script>
/**
 * Six data types that are primitives:
 * Boolean
 * Null
 * Undefined
 * Number
 * String
 * Symbol (new in ECMAScript 6):- “Symbol” value represents a unique identifier.
 * and Object
 *
 **/
// ---------------
// Dynamic typing
// ---------------
varval=10;console.log("type of val: "+typeof(val));// Number
val=10.20;console.log("type of val: "+typeof(val));// Number
val='Hello World';console.log("type of val: "+typeof(val));// String
val=true;console.log("type of val: "+typeof(val));// Boolean
val=null;console.log("type of val: "+typeof(val));// Object
val=undefined;console.log("type of val: "+typeof(val));// Undefined


varobj=newObject();console.log("type of obj: "+typeof(obj));// Undefined
varn;console.log("type of n: "+typeof(n));// null datatype

console.log("type of x: "+typeof(x));// null datatype

// --------------
// let vs var
// --------------

functionvarTest(){
varx=1;
if(true){
varx=2;// same variable!
console.log("var: Inside value of x: "+x);// 2
}
console.log("var: Outside value of x: "+x);// 2
}
varTest();


functionletTest(){
letx=1;
if(true){
letx=2;// different variable
console.log("let: Inside value of x: "+x);// 2
}
console.log("let: Outside value of x: "+x);// 1
}
letTest();

// ----------
// Symbols
// ----------

// id is a new symbol
letid=Symbol();console.log("Type of id: "+typeof(id));

// id is a symbol with the description "id"
letid1=Symbol("id");
letid2=Symbol("id");

console.log("Is id1 == id2: "+(id1==id2));
</script>
<body>
 DataTypes in JavaScript
</body>
</html>