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JSON Tutorial Basic to Advance
JSON stand for Java Script Object Notation (JSON).
JSON is not a Programming Language. JSON is a data interchange format.
Using JSON we can transfer data between client and server and server to server.
JSON is defined in RFC4627 written in 2006. Internet Engineering Task Force (IETF) published JSON RFC7159 in March 2014.
Later on standard updated on RFC8259 and EMCA 404
JSON media type(MIME type) is application/json
JSON file extension is <code>.json</code>
In JSON data can be in following structure
- A collection of name/value pair
- An ordered list of value
These two are the universal data structure supported by approx all programming languages. So data exchange between one language to another is easy by JSON.
JSON string example is as below
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{ "squadName": "Super hero squad", "homeTown": "Metro City", "formed": 2016, "secretBase": "Super tower", "active": true, "members": [ { "name": "Molecule Man", "age": 29, "secretIdentity": "Dan Jukes", "powers": [ "Radiation resistance", "Turning tiny", "Radiation blast" ] }, { "name": "Madame Uppercut", "age": 39, "secretIdentity": "Jane Wilson", "powers": [ "Million tonne punch", "Damage resistance", "Superhuman reflexes" ] }, { "name": "Eternal Flame", "age": 1000000, "secretIdentity": "Unknown", "powers": [ "Immortality", "Heat Immunity", "Inferno", "Teleportation", "Interdimensional travel" ] } ] } |
Why use JSON?
As JSON format is text only, it can be sent to server and also can received from a server, and also can be used as a data format by any programming language.
If you receive data from a server, in JSON format, you can use it like any other JS object.
JSON Syntax
JSON syntax is derived from JS object notation syntax.
• Data is in name/value pairs
• Curly braces hold objects
• Data is separated by commas
• Square brackets hold arrays
JSON Data
JSON data is written as name or value pairs.
A name or value pair consists of a field name like this “”, and it will follow by a colon, and also followed by a value:
Example
{“name”:”Ayan” }
JSON – Evaluates to JS Objects
The JSON format is a also JavaScript objects.
In JSON, keys must be strings, written with double quotes:
JSON
{ “name”:”Ayan” }
In JSON, keys can be strings, numbers, or identifier names,
{ name:”Ayan” }
JSON with JavaScript Syntax
JSON syntax is derived from JavaScript object notation, very little extra software is needed to work with JSON within JS.
With JS you can create an object and assign data to it.
Example
Access a JavaScript object
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<!DOCTYPE html> <html> <body> <p id="mydemo"></p> <script> var myObj, x; myObj = { name: "Ayan", age: 25, city: "Mumbai" }; x = myObj.name; document.getElementById("mydemo").innerHTML = x; </script> </body> </html> |
Result
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<!DOCTYPE html> <html> <body> <p id="mydemo"></p> <script> var myObj, x; myObj = { name: "Ayan", age: 25, city: "Mumbai" }; x = myObj["name"]; document.getElementById("mydemo").innerHTML = x; </script> </body> </html> |
JSON Values
In JSON, values must be one of the following data types:
- a string
- a number
- an object
- an array
or one of the following literal names
- false
- true
- null
JSON String Value
String value is represented in quotation any unicode character is used to create string.
like
” ” //empty string
“Ram” //string value
“\”” // use of escape character
“\uXXXX” // unicode value
JSON Numbers
JSON allows numbers as an integer or a floating point numbers.
Example
25
24.25
3.55
3.1e3
JSON Objects
Values in JSON can be objects. It contains zero or more name value pairs in curly braces seperated by comma
Example
{
“employee”:{ “name”:”Ayan”, “age”:25, “city”:”Mumbai” }
}
JSON Array
JSON Array are surrounded by [ (squrae bracket) and zero or more values or elements are seperated by comma.
The values in array may be of different types.
Example
A composite JSON structure is also possible
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[ { "name":"Ayan Das", "age":25, "knowledge":["typing","SEO"] }, { "name":"RamBag", "age":39, "knowledge":["Coding","Web designing"] } ] |
Here a JSON array contains two objects and each object contains string, number and array values
JSON is purely a data format — it contains only properties, no methods.
- JSON need a double quotes to be used around strings and property names. Single quotes are not valid in a JSON.
- A single misplaced colon or comma can cause a JSON file to go wrong, and not working that JSON file. Always be careful to validate any data in JSON. A validate JSON using an application like JSONLint.
- JSON can be taken the form of any data type that is valid for inside JSON, not just arrays or objects. So, a single string or a number can be a valid JSON object.
- Unlike in JavaScript code in which object properties may be unquoted, in JSON, only quoted strings may be used as properties.
Converting between objects and textSection
In JSON can be set the XHR request to convert the JSON response directly into a JS object using:
request.responseType = ‘json’;
But sometimes can be receive a raw JSON string, and need to convert it to an object.
when try to send a JavaScript object across the network, then need to convert it to JSON (a string) before sending.
These two problems are so common that a built-in JSON object is available, which contains the following two methods:
- parse(): Accepts a JSON string as a parameter, and returns the corresponding JavaScript object.
- stringify(): Accepts an object as a parameter, and returns the equivalent JSON string form.
See one example of stringify()
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request.open('GET', requestURL); <!DOCTYPE html> <html lang="en"> <body> <script> var person = new Object(); person.name = "Ram"; person.age = 24; person.mailIds = [ var JSONtext = JSON.stringify(person); document.write(JSONtext); </script> </body> </html> |
console.table(obj); prints array in tabular format
console.log(obj[0].name); print first objects name
for (var row in obj) will iterate each object and access its properties in name value pair
Example
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<!DOCTYPE html> <html> <body> <p id="mydemo"></p> <script> var text = '{"employees":[' + '{"firstName":"Ram","lastName":"Das" },' + '{"firstName":"Sam","lastName":"Ghosh" },' + '{"firstName":"Ayan","lastName":"Bag" }]}'; obj = JSON.parse(text); document.getElementById("mydemo").innerHTML = obj.employees[1].firstName + " " + obj.employees[1].lastName; </script> </body> </html> |
Sam Ghosh
JSON.parse()
A common use of JSON is to exchange data to/from a web server.
parse() is used to convert JSON data to JavaScript values
Server send data as a string. To convert this string to JavaScript object JSON.parse() method is used
Example – Parsing JSON
This text received from a web server:
‘{ “name”:”Ayan”, “age”:25, “city”:”Mumbai”}’
Use the JavaScript function JSON.parse() to convert text into a JavaScript object:
varobj = JSON.parse(‘{ “name”:”Ayan”, “age”:25, “city”:”Mumbai”}’);
Use the JavaScript function JSON.parse() to convert text into a JavaScript object:
Example
Create Object from JSON String
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<!DOCTYPE html> <html> <body> <p id="mydemo"></p> <script> var txt = '{"name":"Ayan", "age":25, "city":"Mumbai"}' var obj = JSON.parse(txt); document.getElementById("mydemo").innerHTML = obj.name + ", " + obj.age; </script> </body> </html> |
Ayan, 25
How to access nested JSON objects
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<!DOCTYPE html> <html> <body> <p id="mydemo"></p> <script> var myObj = { "name":"Ayan", "age":25, "bikes": { "bike1":"Honda", "bike2":"Bajaj", "bike3":"Hero" } } document.getElementById("mydemo").innerHTML += myObj.bikes.bike2 + "<br>"; //or: document.getElementById("mydemo").innerHTML += myObj.bikes["bike2"]; </script> </body> </html> |
Bajaj Bajaj
JSON Arrays
EXAMPLE
Access an array value of a JSON object
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<!DOCTYPE html> <html> <body> <p id="mydemo"></p> <script> var myObj, x; myObj = { "name":"Ayan", "age":25, "bikes":[ "Honda", "Bajaj", "Hero" ] }; x = myObj.bikes[0]; document.getElementById("mydemo").innerHTML = x; </script> </body> </html> |
Honda
EXAMPLE
Looping through an array using a for in loop
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<!DOCTYPE html> <html> <body> <p id="mydemo"></p> <script> var myObj, i, x = ""; myObj = { "name":"Ayan", "age":25, "cars":[ "Honda", "Bajaj", "Hero" ] }; for (i in myObj.cars) { x += myObj.cars[i] + "<br>"; } document.getElementById("mydemo").innerHTML = x; </script> </body> </html> |
Honda Bajaj Hero
EXAMPLE
Looping through arrays inside arrays
Nested JSON Objects
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<!DOCTYPE html> <html> <body> <p id="mydemo"></p> <script> var myObj, i, j, x = ""; myObj = { "name":"Ayan", "age":25, "bikes": [ {"name":"Honda", "models":["Hornet", "xblade", "livo"]}, {"name":"Bajaj", "models":["pulsar", "neon", "X5"]}, {"name":"Hero", "models":["500", "Panda"] } ] } for (i in myObj.bikes) { x += "<h1>" + myObj.bikes[i].name + "</h1>"; for (j in myObj.bikes[i].models) { x += myObj.bikes[i].models[j] + "<br>"; } } document.getElementById("mydemo").innerHTML = x; </script> </body> </html> |
Honda Hornet xblade livo Bajaj pulsar neon X5 Hero 500 Panda
See one Example to read JSON data and show in console
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<!DOCTYPE html> <html> <body> <script> var json = `[{ "rollno": 12, "name": "Ram", "section": "A", "branch": "CSE" }, { "rollno": 14, "name": "Mohan", "section": "A", "branch": "CSE" }, { "rollno": 15, "name": "Sohan", "section": "B", "branch": "CSE" }, { "rollno": 16, "name": "Ramesh", "section": "A", "branch": "Mech" }, { "rollno": 17, "name": "Suresh", "section": "A", "branch": "Mech" }, { "rollno": 18, "name": "Mahesh", "section": "B", "branch": "Mech" }, { "rollno": 19, "name": "Naresh", "section": "A", "branch": "ET&T" } ]`; var obj = JSON.parse(json); console.table(obj); console.log(obj[0].name); for (var row in obj) { console.log(" RollNo "+obj[row].rollno +" Name "+obj[row].name +" Section "+obj[row].section +" Branch "+obj[row].branch); } </script> </body> </html> |
Result
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Ram RollNo 12 Name Ram Section A Branch CSE RollNo 14 Name Mohan Section A Branch CSE RollNo 15 Name Sohan Section B Branch CSE RollNo 16 Name Ramesh Section A Branch Mech RollNo 17 Name Suresh Section A Branch Mech RollNo 18 Name Mahesh Section B Branch Mech RollNo 19 Name Naresh Section A Branch ET&T |
JSON Vs XML
Extensible Markup Language(XML) is a Markup Language.
XML is used to access and transfer the data same like JSON.
XML uses tag to wrap content.
General structure of XML to send send data is as below
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<?xml version="1.0" encoding="UTF-8"?> <students> <student> <rollno>12</rollno> <name>Ram</name> <section>CSE</section> <branch>A</branch> </student> <student> <rollno>14</rollno> <name>Mohan</name> <section>CSE</section> <branch>A</branch> </student> </students> |
For above data JSON is
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[{ "rollno": 12, "name": "Ram", "section": "A", "branch": "CSE" }, { "rollno": 14, "name": "Mohan", "section": "A", "branch": "CSE" }] |
XML and JSON both are data interchange format.
In XML we have to add additional tags to carry data that is not is JSON no overhead required to carry data in JSON
JSON is based on JavaScript. XML is derived from SGML.
JSON can use Array and objects to represent and carry data. XML uses markup structure to carry data
JSON uses key value pair and array object that allows direct mapping of data structure of appropriate language.
XML allows namespace to avoid name conflicts this is not available in JSON.
JSON Formatter and Validator
JSON Formatter are used to provide structure way to JSON data.
JSON validators are tool that are used to validate JSON data.
Why JSON formatter and validator required.
If you get data from server it is in unformatted way
Like I get JSON data from url
api.openweathermap.org/data/2.5/weather?q=London
This will provide me weather information of London
Above JSON data is difficult to read we have to format above data to make it readable.
Few online tools that can be used are
and many more
put code received from URL to any one validator that validate and structure the data so that it can be readable
select angularjs
Angularjs provides way to bind HTML select element with angularjs model
select directive also provide dynamic option value using ng-repeat and ng-options
When the item from select element is get selected from option then it is bind with the value of ng-model associated with select element using angularjs two way binding.
Setting option value using value attribute of option element will set this value as string.
On selection this value in ng-model the model variable must be string type.
https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.7.8/angular.min.jsselect is
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<select ng-model="string" [name="string" ]="" [multiple="string" [required="string" [ng-required="string" [ng-change="string" [ng-options="string" [ng-attr-size="string"> ... </select> |
description of parameters fields are self explanatory.
To access value in model you have to provide modal name rest attributes are optional as per requirement any one can use.
let us see one basic example for selecting a value in model
Example
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<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.9/angular.min.js"></script> <div ng-app="myApp" ng-controller="selectController"> <form name="myForm"> <label for="favouriteColor"> Select You Favourite Color: </label><br> <select name="favouriteColor" ng-model="favouriteColor"> <option value="red">Red</option> <option value="green">Green</option> <option value="blue">Blue</option> <option value="orange">Orange</option> </select><br> you have selected: {{favouriteColor}} </form> </div> <script> var app = angular.module('myApp', []); app.controller('selectController', function($scope) { }); </script> |
populating select with dynamic values
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<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.9/angular.min.js"></script> <div ng-app="myApp" ng-controller="selectController1"> <form name="myForm"> <label for="favouriteColor"> Select You Favourite Color: </label><br> <select name="favouriteColor" ng-model="favouriteColor"> <option ng-repeat="color in colors" ng-value="color">{{color}}</option> </select><br> you have selected: {{favouriteColor}} </form> </div> <script> var app = angular.module('myApp', []); app.controller('selectController1', function($scope) { $scope.colors=["Red","Greed","Blue","Orange"]; }); </script> |
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<!DOCTYPE html> <html> <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.9/angular.min.js"></script> <body> <div ng-app="myApp" ng-controller="selectController2"> <form name="myForm"> <label for="favouriteColor"> Select You Favourite Color: </label><br> <select name="favouriteColor" ng-model="favouriteColor"> <option ng-repeat="color in colors" ng-value="color.id">{{color.name}}</option> </select><br> you have selected: {{favouriteColor}} </form> </div> <script> var app = angular.module('myApp', []); app.controller('selectController2', function($scope) { $scope.colors=[{id:1, name:"Red"}, {id:2,name:"Greed"}, {id:3,name:"Blue"}, {id:4, name:"Orange"} ]; }); </script> </body> </html> |
To select multiple in above program use multiple with select element as below
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<select name="favouriteColor" ng-model="favouriteColor" multiple=""> <option ng-repeat="color in colors" ng-value="color.id">{{color.name}}</option> </select><br> |
by holding control key with click can select multiple values
Using ng-option with select to generate dynamic option value
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<!DOCTYPE html> <html> <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.9/angular.min.js"></script> <body> <div ng-app="myApp" ng-controller="selectController2"> <form name="myForm"> <label for="favouriteColor"> Select You Favourite Color: </label><br> <select name="favouriteColor" ng-model="favouriteColor" ng-options="color.id as color.name for color in colors" >{{color.name}}</option> </select><br> you have selected: {{favouriteColor}} </form> </div> <script> var app = angular.module('myApp', []); app.controller('selectController2', function($scope) { $scope.colors=[{id:1, name:"Red"}, {id:2,name:"Greed"}, {id:3,name:"Blue"}, {id:4, name:"Orange"} ]; }); </script> </body> </html> |
pre populating any specific value in ng-options is easy in following example you can see this.
Consider we have to populate Blue as default value then set $scope.favouriteColor=3 in controller
see below
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$scope.favouriteColor=3; |
JavaScript Overlays
There are different kinds of overlays for modal dialogs for prompting,
overlays for info or warning boxes, tabbed overlays, alerting usersoverlays for displaying complex data.
The overlay can implement on HTML like images, links, forms, tables, any type of div and any can be styled with CSS, like rounded borders, shadows or gradients etc.
Core behaviors are configurable such as positioning, animation durations and closing the overlay.
Overlay offers a good container for other tools. Think of scrollables, tabs or accordions inside the Overlay.
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<html> <head> <meta name="viewport" content="width=device-width, initial-scale=1"> <style> #overlay { position: fixed; display: none; width: 100%; height: 100%; top: 0; left: 0; right: 0; bottom: 0; background-color: rgba(0,0,0,0.5); z-index: 2; cursor: pointer; } </style> </head> <body> <div id="overlay" onclick="off()"></div> <div> <button onclick="on()">On the overlay effect</button> </div> <script> function on() { document.getElementById("overlay").style.display = "block"; } function off() { document.getElementById("overlay").style.display = "none"; } </script> </body> </html> |
Array of pointers in C Programming
Example: Write a program to assign the address of array elements to pointer variable and print the array element with address.
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#include <stdio.h> int main () { int arr[] = {10, 20, 30}; int i, *ptr[3]; for ( i = 0; i < 3; i++) { ptr[i] = &arr[i]; // assign the address array element to pointer variable } for ( i = 0; i < 3; i++) { printf("\n Value of arr[%d] = %d", i, *ptr[i] ); printf("\n Address of arr[%d] = %d", i, ptr[i] ); } return 0; } |
OUTPUT
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Value of arr[0] = 10 Address of arr[0] = 1392582964 Value of arr[1] = 20 Address of arr[1] = 1392582968 Value of arr[2] = 30 Address of arr[2] = 1392582972 |
While Statement in C Programming
“while loop” repeats a set of statements if condition is true. If condition is false the flow of control do not enter inside of while loop.
It first tests the condition then execute the body of loop.
Syntax of a while statement−
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while(condition) { Statement1; Statement2; ---- ---- Increment/Decrement; } |
Example: Write a program to print 1 to 10 using while loop.
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#include <stdio.h> int main() { int a = 1; while (a <= 10) // loop executes 10 times { printf(" %d \n", a); a++; } return 0; } |
OUTPUT
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1 2 3 4 5 6 7 8 9 10 |
Description: In the above program, line “while( a <= 10 )” will check if condition is true or false.
In the above case when a=1, condition is true and flow of control move inside of while and print 1 after that increment occurs.
Now a=2, again condition is true and flow of control move inside of while and print 2 after that increment occurs.
Now a=3, again condition is true and flow of control move inside of while and print 3 after that increment occurs.
This process is continue until condition is false(in this case condition false occur when a=11).
Example: Write a program to print 10 to 1 using while loop.
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#include <stdio.h> int main() { int a = 10; while (a > 0) // loop executes 10 times { printf(" %d \n", a); a--; } return 0; } |
OUTPUT
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10 9 8 7 6 5 4 3 2 1 |
Switch Statement in C Programming
“switch” is a case control structure.
It contains case and default values.
“switch” statement takes a value as a expression for equality testing against a list of values/case.
syntax for a switch statement:-
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switch (expression) { case constant-expression: statement(s); break; /* optional */ case constant-expression: statement(s); break; /* optional */ /* you can have any number of case statements */ default: /* Optional */ statement(s); } |
Rules of switch statement −
In a “switch” statement we can have any number of case.
for equality testing against a list of values/case, constant-expression for a case must be the same data type as the variable in the switch expression.
When “switch” expression value is equal to a case, the statements following that case will execute until a break statement is reached/executes.
When a break statement is reached/executes, the switch statement terminates, and the control jumps to the outside of switch.
a break is a optional. If there is no break in the switch case, the flow of control will jump to the next case of switch until a break is reached.
A switch statement also have a default case, which appear at the end of the switch. when none of the cases is true then default case will execute.
No break is needed in the default case. “default” case is also an optional.
Example: Write a program to take one numbers from user between 1 to 3. Write entered number in words if number between 1 to 3 otherwise print wrong number using switch.
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# include <stdio.h> int main() { int n; printf(" enter number between 1 to 3"); scanf("%d", &n); switch (n) { case 1: printf("\n one"); break; case 2: printf("\n two"); break; case 3: printf("\n three"); break; default: printf("\n wrong number"); } return 0; } |
OUTPUT
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enter number between 1 to 3 2 // user entered 2 two |
Note: In the above program, for example user enters a number 6 then output will be as follows:
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enter number between 1 to 3 6 // user entered 6 wrong number |
Example: Write a program using switch statement but without break.
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#include <stdio.h> int main() { char c = 'B'; switch (c) { case 'A': printf("Excellent!\n"); break; case 'B': case 'C': printf("Well done\n"); case 'D': printf("You passed\n"); break; case 'F': printf("Better try again\n"); break; default: printf("Invalid Character \n"); } return 0; } |
OUTPUT
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Well done You passed |
Description: Because if there is no break in the switch case, the flow of control will jump to the next case of switch until a break is reached.
Note: In the above program, for example value of char variable c = ‘ A’ then the output will be as follows:
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Excellent |
Nested switch statements
In C programming language we can define switch statement within another switch.
Syntax for a nested switch statement: −
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switch (ch1) { case constant - expression: printf("case A of outer switch"); switch (ch2) { case constant - expression: printf("case A of inner switch"); break; case constant - expression: /* case code */ } break; case 'B': /* case code */ } |
if else statement in C programming
In the C language decision making statement is executes if the given condition is true otherwise conditional block will never execute.
In C language non-zero and non-null values are consider as true, and zero or null values are consider false.
if statement
Syntax of an if statement −
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if(expression) { statements; } |
In a if statement if the expression result is non zero true, then the block of statement of the ‘if’ statement will be executed. If the expression result is zero, then the block of statement of the ‘if’ statement will not executed and control sent to the next line of if block.
Example: Write a program to demonstrate the ‘if’ statement.
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#include <stdio.h> int main() { int x = 10; int y = 25; if (x < y) // condition x<y is true it returns 1 therefore if block will execute { printf("Sum of x+y = %i", (x + y)); } printf("\n after if statement %d",z); return 0; } |
OUTPUT
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Sum of x+y = 35 after if statement |
In the above program if(x>y) then the condition will be false and ‘if’ block will never execute.
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#include < stdio.h ><br> int main() {<br> int x = 10;<br> int y = 25;<br> if (x > y) // condition x>y is false therefore if block will not execute <br> {<br> printf("Sum of x+y = %i", (x + y));<br> }<br> printf("\n after if statement");<br> return 0;<br> }<br> |
OUTPUT
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after if statement |
if-else statement
Syntax of an ‘if-else’ statement −
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if(expression) { statements } else { statements } |
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In a ‘if-else’ statement if the expression is <strong>non zero, </strong>then the block of statements of the 'if' statement will be executed. If the statement expression is <strong>zero,</strong> then the block of code of the 'else' statement will executed.<br><br> |
Example: Write a program to take two numbers from user and find the grater between them using ‘if-else’ statement.
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#include <stdio.h> int main() { int x; int y; printf("enter 1st number"); scanf("%d", & x); // 10 printf("enter 2 nd number"); scanf("%d", & y); // 30 if (x > y) // check condition x>y { printf("grater value= %d", x); } else { printf("\n grater value= %d", y); } return 0; } |
OUTPUT
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enter 1st number 34 enter 2 nd number 2 grater value= 34 |
Nested If else
In a C language we can use if statement inside another if statement(s).
Syntax of an ‘nested -if’ statement −
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if(expression1) { statements If (expression2) { statements } } |
Example: Write a program to take two numbers from user if both number are between 1 to 9 then print “Good” using nested-if statement.
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# include < stdio.h > int main() { int x; int y; printf("enter 1st number"); scanf("%d", & x); // 5 printf("enter 2nd number"); scanf("%d", & y); // 7 if (x < 10) // check condition x<10 { if (y < 10) // nested-if, check condition y<10 { printf("Good"); } } return 0; } |
OUTPUT
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enter 1st number3 enter 2nd number2 Good |
Nested if else statement
In a C language we can use if or if-else statement inside another if or if-else statement(s).
Syntax of an ‘if-else’ statement −
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if(expression1) { statements if (expression2) { statements } } else { if (expression3) { statements } } |
Example: Write a program to take three numbers from user and find the grater among them using ‘nested if-else’ statement.
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#include <stdio.h> int main() { int n1, n2, n3; printf("Enter three numbers: "); scanf("%d %d %d", &n1, &n2, &n3); if (n1 >= n2) { if (n1 >= n3) { printf("The largest number= %d", n1); } else { printf("The largest number = %d ", n3); } } else { if (n2 >= n3) { printf("The largest number= %d", n2); } else { printf("The largest number=%d", n3); } } return 0; } |
OUTPUT
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Enter three numbers: 20 10 30 The largest number= 30 |
If else ladder
some times if can be nested inside else as below
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if (expression1) { statements; } else { if (expression2) { statements; } else { if (expression3) { statements; } } } } |
above statements can be written as
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if (expression1) { statements; } else if (expression2) { statements; } else if (expression3) { statements; } else { statements; } |
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#include <stdio.h> int main() { int per; printf("Enter your percentage of marks: "); scanf("%d", &per); if (per>90) { printf("Your Gread is O"); } else if (per>80) { printf("Your Gread is E"); } else if (per>70) { printf("Your Gread is A"); } else if (per>60) { printf("Your Gread is B"); } else if (per>50) { printf("Your Gread is C"); } else if (per>40) { printf("Your Gread is D"); } else if (per>30) { printf("Your Gread is F"); } return 0; } |
OUTPUT
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Enter your percentage of marks:91 Your Gread is O |
Assignment Operators in C Programming
In a C language there are following assignment operators −
| Operator | Description | Example |
|---|---|---|
| = | assignment operator (it assigns values of right side operands to left side operand ) | a=5 |
| += | Add assignment operator | a+=5 |
| -= | Subtract assignment operator | a-=5 |
| *= | Multiply assignment operator | a*=5 |
| /= | Divide assignment operator | a/=5 |
| %= | Modulus assignment operator | a%=5 |
| <<= | Left shift assignment operator | a<<=5 |
| >>= | Right shift assignment operator | a>>=5 |
| &= | Bitwise AND assignment operator | a&=5 |
| ^= | Bitwise exclusive OR assignment operator | a^=5 |
| |= | Bitwise inclusive OR assignment operator | a|=5 |
EXAMPLE: Use of assignment operators with arithmetic operators
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#include <stdio.h> int main() { int a = 10; a +=5; // 15 (a=a+5) printf("\nsum is %d",a); a-=5; //10 (a=a-5) printf("\nsub is %d",a); a*=5; //50 (a=a*5) printf("\nmul is %d",a); a/=5; //10 (a=a/5) printf("\ndiv is %d",a); a%=5; printf("\nmod is %d",a); return 0; } |
Output
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sum is 15 sub is 10 mul is 50 div is 10 mod is 0 |
EXAMPLE: Use of assignment operators with bitwise operators
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# include < stdio.h > int main() { int a = 10; a <<= 2; // 15 (a=a+5) printf("\nleft shift is %d", a); a >>= 2; //10 (a=a-5) printf("\nright shift is %d", a); a &= 2; //50 (a=a*5) printf("\nbitwise and is %d", a); a ^= 2; //10 (a=a/5) printf("\nbitwise xor is %d", a); a |= 2; printf("\nbitwise or is %d", a); return 0; } |
Output
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left shift is 40 right shift is 10 bitwise and is 2 bitwise xor is 0 bitwise or is 2 |
Bitwise Operators in C Programming
In a C programming language Bitwise operator works on bits and perform bit-by-bit operation. There are following bitwise operators in C:-
| Operator | Description | Example |
|---|---|---|
| & | Binary AND Operator | a & b |
| | | Binary OR Operator | a| b |
| ^ | Binary XOR Operator | a^b |
| ~ | Binary One’s Complement Operator is unary | ~a |
| << | Binary Left Shift Operator | a<<b |
| >> | Binary Right Shift Operator | a>>b |
The truth tables for &, |, and ^ is as follows –
| a | b | a & b | a | b | a ^ b |
|---|---|---|---|---|
| 0 | 0 | 0 | 0 | 0 |
| 0 | 1 | 0 | 1 | 1 |
| 1 | 1 | 1 | 1 | 0 |
| 1 | 0 | 0 | 1 | 1 |
Assume A = 60 and B = 13 in binary format, they will be as follows −
A in binary = 0011 1100 (60)
B in binary = 0000 1101 (13)
Bitwise AND (&)
A = 0011 1100 (60)
& B = 0000 1101 (13)
———————————————————
0000 1100 (12)
Bitwise OR (|)
A = 0011 1100 (60)
| B = 0000 1101 (13)
———————————————————
0011 1101 (61)
Bitwise XOR (|)
A = 0011 1100 (60)
^ B = 0000 1101 (13)
———————————————————
0011 0001 (49)
Binary Left Shift Operator
Left shift operator shift all the bits in a left direction to specified number of times.
i=16 //0001 0000
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i = i <<2; // 0100 0000 (shift left 2 bits, front 2 bits will be lost and appended 2 zero |
Example:
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#include<stdio.h> int main() { int i = 16; // 0001 0000 i = i>>2; // 0000 0100 (shift right 2 bits, last 2 bits will be lost, and 2 zero add in front) printf("i = %d", i); return 0; } |
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i=64 |
Binary Right Shift Operator
Left shift operator shift all the bits in a left direction to specified number of times.
int i = 16; // 0001 0000
i = i>>2; // 0000 0100 (shift right 2 bits, last 2 bits will be lost, and 2 zero add in front)
Example
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#include<stdio.h> int main() { int i = 16; // 0001 0000 i = i>>2; // 0000 0100 (shift right 2 bits, last 2 bits will be lost, and 2 zero add in front) printf("i = %d", i); return 0; } |
Output
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i=4 |
Exapmle: Write a program to demonstrate Bitwise operator.
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#include <stdio.h> int main() { int a = 60; int b = 13; int c, d, e, f, g, h; c = ~a; //c = -61 d = a | b; //d= 61 e = a & b; // e= 12 f = a ^ b; //f= 49 printf("\n value of c = %d", c); printf("\n value of d = %d", d); printf("\n value of e = %d", e); printf("\n value of f = %d", f); g = h = 16; g = g << 2; //g= 64 h = h >> 2; // h=4; printf("\n value of g = %d", g); printf("\n value of h = %d", h); } |
OUTPUT
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value of c = -61 value of d = 61 value of e = 12 value of f = 49 value of g = 64 value of h = 4 |
Relational Operators in C Programming
C Language has a following relational operators. For example: Assume variable A holds 100 and variable B holds 200 then −
| Operator | Description | Example |
|---|---|---|
| == | Equals to | (A == B) is not true. |
| != | Not equal | (A != B) is true. |
| > | Greater than | (A > B) is not true. |
| < | Less than | (A < B) is true. |
| >= | Greater than or equals to | (A >= B) is not true. |
| <= | Less than or equals to | (A <= B) is true. |
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#include < stdio.h > int main() { int a, b, big; a = 10; b = 20; if (a > b) // if condition is true move inside if-statement { big = a; } else { big = b; } printf("Biggest of the two number is = %d", big); return 0; } |
Output
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Biggest of the two number is = 20 |