JavaScript Lab Works

For Lab Report : Program 1 to 15

Program 1. Write Java Script program to display date and time. [Use Date() object]
<script type="text/javascript"> var months = ["Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"]; var m = new Date(); var dateString = m.getDate() +" "+ (months[m.getMonth()]) +" "+ m.getFullYear() + " " + m.getHours() + ":" + m.getMinutes(); document.write(dateString); </script>
Program 2. Write a program using JavaScript to test whether the given number is even or odd.
<script type="text/javascript"> var num; num=parseInt(prompt("Enter any number : ")); if(num%2==0) document.write (" Even number "); else document.write ("Odd number "); </script>
Program 3. Write a program using JavaScript to display greatest number among three entered numbers by user.
<script type="text/javascript"> var num1,num2,num3; num1=parseInt(prompt("Enter first number : ")); num2=parseInt(prompt("Enter second number : ")); num3=parseInt(prompt("Enter third number : ")); if(num1>num2&&num1>num3) document.write (" Greatest number = "+num1); else if(num2>num1&&num2>num3) document.write (" Greatest number = "+num2); else document.write (" Greatest number = "+num3); </script>
Program 4. Write a program using JavaScript to find square root of given number.
<script type="text/javascript"> var num,sq; num=parseInt(prompt("Enter any number : ")); sq=Math.sqrt(num); document.write ("Square root of "+num + " is " +sq); </script>
Program 5.Write a program to input your name and age using form and know whether he/she is eligible to vote or not. [ Use function and onclick event]
<form name="myForm"> <input type="text" name="username" placeholder="Enter name"> <br><br> <input type="text" name="age" placeholder="Enter age"> <br><br> <input type="button" value="Click here" onclick="test()"> </form> <script type="text/javascript"> function test() { var naam=document.myForm.username.value; var a=document.myForm.age.value; if(a>18) document.write("You can vote "+naam); else document.write("sorry! You can't vote "+naam); } </script>
Program 6. Write a program to input a string using form and convert that into uppercase.[Use string object toUpperCase()]
<form name="myForm"> <input type="text" name="stringData" placeholder=" Enter any string "> <br><br> <input type="button" value="Click here" onclick="convertUpper()"> <p id="ans"></p> </form> <script type="text/javascript"> function convertUpper() { var text = document.myForm.stringData.value; var result = text.toUpperCase(); document.getElementById("ans").innerHTML = result; } </script>
Program 7. Write a program to print odd numbers between 1 to 100 using while loop. Use function.
<input type="button" onclick="oddNumbers()" value="start"> <script type="text/javascript"> function oddNumbers() { var i=1; while(i<=100) { document.write(i +" "); i=i+2; } } </script>
Program 8. Write a program to reverse a given string. [use loop from its length-1 to 0 and print it]
<script type="text/javascript"> var s,i; s=prompt("Enter any sting : "); for(i=s.length-1;i>=0;i--) { document.write(s[i]); } </script>
Program 9. An array contains some string data. Print them.
<script type="text/javascript"> var day=new Array(7); var day = ["Sun","Mon","Tues","Wed","Thur","Fri","Sat"]; document.write(day); </script>
Program 10. An array contains some data. Print them in reverse order.[use array.reverse() method].
<script type="text/javascript"> var day = ["Sun","Mon","Tues","Wed","Thur","Fri","Sat"]; document.write (day.reverse()); </script>
Program 11. Write a program to insert a string "We are learning Java Script" via form object getElementById() method.Use paragraph with id.
<p id="result"> </p> <script type="text/javascript"> document.getElementById("result").innerHTML ="We are learning Java Script"; </script>
Program 12. Input your name and grade using form. Validate this with a message "This field is required", onclick.
<!DOCTYPE html> <html> <head> <title>JavaScript Validation</title> </head> <body> <form name="myForm" method="post" onsubmit="return validateForm()"> <input type="text" name="user" placeholder="Enter name"> <br> <span id="usererror" class="error"></span> <br> <input type="text" name="grade" placeholder="Enter grade"> <br> <span id="gradeerror" class="error"></span> <br> <input type="submit" value="Login"> </form> <script type="text/javascript"> function validateForm() { var uname=document.myForm.user.value; var g=document.myForm.grade.value; if (uname==""){ document.getElementById("usererror").innerHTML="This field is required"; return false; }else if(g==""){ document.getElementById("gradeerror").innerHTML="This field is required"; return false; } } </script> <style type="text/css"> .error{ color: red; } </style> </body> </html>
Program 13. Write any two paragraphs in your html page. Now write a program using jquery to hide that written paragraphs as you click on that.
<!DOCTYPE html> <html> <head> <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"> </script> <script> $(document).ready(function(){ $("p").click(function(){ $(this).hide(); }); }); </script> <body> <h2> Simple Example of jQuery </h2> <p> This is a sample paragraph </p> </body> </html>
Program 14. Use Jquery to create an alert message for a button.
<!DOCTYPE html> <html> <head> <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"> </script> <script> $(document).ready(function(){ $("button").click(function(){ alert("You clicked"); }); }); </script> <body> <button>Click here</button> </body> </html>
Program 15. Use Jquery to show concept of slide effect.[Use slide() method]
<!DOCTYPE html> <html> <head> <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.0/jquery.min.js"></script> <script> $(document).ready(function(){ $("#flip").click(function(){ $("#panel").slideToggle("slow"); }); }); </script> <style> #panel, #flip { padding: 5px; text-align: center; background-color: #f2f2f2; border: solid 1px ; } #panel { padding: 50px; display: none; } </style> </head> <body> <div id="flip">Click to view and hide</div> <div id="panel">My Dear Students ! <BR> Welcome to PLK computer SIR site</div> </body> </html>

Bonus Programs

Program 3. Write a program using JavaScript to calculate simple interest.
<script> var p,t,r,si; p=parseInt(prompt("Enter Principal : ")); t=parseInt(prompt("Enter Time : ")); r=parseInt(prompt("Enter Rate : ")); si=(p*t*r)/100; document.write ("Simple Interest is " +si); </script>
Program 4. Write a program using JavaScript to display first ten natural numbers.
<script> var i; for(i=1;i<=10;i++) { document.write("<br>"+ i); } </script>
Program 5. Write a function to add any two numbers in Javascript.
<form> Enter First Number: <input type="text" name="number1" id="number1"> <br> <br> Enter Second Number: <input type="text" name="number2" id="number2"> <br> <br> <button type="button" onclick="total()"> Click for Result </button> <p id="result"> </p> </form> <script> function total(){ var num1 = document.getElementById("number1").value; var num2 = document.getElementById("number2").value; var sum = parseInt(num1) + parseInt(num2); document.getElementById("result").innerHTML= num1 + " + " + num2 + " = " + sum; } </script>
Program 6. Write a function to find factorial of given number using Javascript.
<form> Enter a number : <input type="text" name="num" id="num"> <br><br> <button type="button" onclick="fact()"> Click for result </button> <p id="ans"> </p> </form> <script> function fact() { var f=1,i,num; num=document.getElementById("num").value; for(i=1;i<=num;i++) { f=f*i; } document.getElementById("ans").innerHTML="Factorial of " +num + " is " + f; } </script>
Program 7. Write a JavaScript program to show password. (Toggle between password)
<input type="Password" id="pass" placeholder="Type password"><br><br> <input type="checkbox" onclick="myFunction()"> Show Password <script type="text/javascript"> function myFunction() { var x = document.getElementById("pass"); if (x.type == "password") { x.type = "text"; } else { x.type = "password"; } } </script>

Form Validation

Program 8. Write JavaScript to validate a html form containing username and password. Program should display the error message when username and password is blank.
<!DOCTYPE html> <html> <head> <title>JavaScript Validation</title> </head> <body> <form name="myForm" method="post" onsubmit="return validateForm()"> <p> <input type="text" name="user" placeholder="username"> <br> <span id="usernameerror" class="error"></span> </p> <p> <input type="password" name="pass" placeholder="password"> <br> <span id="passworderror" class="error"></span> </p> <p> <input type="submit" value="Login"> </p> </form> <script type="text/javascript"> function validateForm() { var uname=document.myForm.user.value; var password=document.myForm.pass.value; if (uname==null || uname==""){ document.getElementById("usernameerror").innerHTML="Enter username"; return false; }else if(password==null || password==""){ document.getElementById("passworderror").innerHTML="Enter your password"; return false; } } </script> <style type="text/css"> .error{ color: red; } </style> </body> </html>
Program 9. Write JavaScript to validate a html form containing username and password. Program should display the error message when username is blank and mobile number is less than 10 digit.
<!DOCTYPE html> <html> <head> <title>JavaScript Validation</title> </head> <body> <form name="myForm" method="post" onsubmit="return validateForm()"> <p> <input type="text" name="user" placeholder="username"> <br> <span id="usernameerror" class="error"></span> </p> <p> <input type="text" name="mobileno" placeholder="mobile number"> <br> <span id="mobilenoerror" class="error"></span> </p> <p> <input type="submit" value="Login"> </p> </form> <script type="text/javascript"> function validateForm() { var uname=document.myForm.user.value; var mobileno=document.myForm.mobileno.value; if (uname==null || uname==""){ document.getElementById("usernameerror").innerHTML="Enter username"; return false; }else if(mobileno.length<10){ document.getElementById("mobilenoerror").innerHTML="Enter ten digit mobile no"; return false; } } </script> <style type="text/css"> .error{ color: red; } </style> </body> </html>
Program 10. Write JavaScript to validate confirm password or re-type password.
<!DOCTYPE html> <html> <head> <title>Retype Password Validation</title> <script type="text/javascript"> function validatePassword() { var password1=document.myForm.firstpass.value; var password2=document.myForm.secondpass.value; if(password1==password2) { alert("password matched"); return true; } else { alert("Both password must be same"); return false; } } </script> </head> <body> <form name="myForm" onsubmit="return validatePassword()"> <input type="password" name="firstpass" placeholder="Type your Password"> <br><br> <input type="password" name="secondpass" placeholder="Again type Password"> <br><br> <input type="submit"> </form> </body> </html>