i just got the code below and i found that i need to do the parseInt() function..That means i need use this function to find a integer answer for my BMI answer.
<!DOCTYPE html>
<html>
<head>
<title>
Calculate your BMI
</title>
<script type=text/javascript>
function CalculateBmi(){
var weight= document.getElementsByName('weight')[0].value;
var height= document.getElementsByName('height')[0].value;
if(weight>0 && height>0){
var finalBMI=(weight/(height*height))*703;
document.getElementsByName('BMI')[0].value=finalBMI;
}
}
</script>
</head>
<body>
<form name="Form">
weight in pounds
<input type="text" name="weight" />
<br/>
height in inches
<input type="text" name="height"/>
<br/>
<input type="button" value="calculate BMI" onclick="CalculateBmi()">
<br />
BMI result
<input type="text" name="BMI"/>
</form>
</body>
</html>
The code above is what i did, i have try to put () in the co such as
document.getElementsByName('BMI')[0].value=ParseInt(finalBMI);
but i am sure i miss something.
var weight= parseInt(document.getElementsByName('weight')[0].value, 10);
var height= parseInt(document.getElementsByName('height')[0].value, 10);
Next time, please show us your attempts in the question!
Related
I am getting back into javascript for a job I am going to start soon. for some reason i forgot how to do a simple calculator. I dont understand why my even onclick is null when it is a button. I am sure this is a very simple answer I just cant see it.
if(document.getElementById("add").onclick == true){
alert("hey");}
<!DOCTYPE html>
<html>
<head>
<title>TEST</title>
<script src= "script.js"> </script>
</head>
<body>
<h3> Calculator: </h3>
<input type="text" name="a">
<input type="text" name="b">
<input type="button" value="+" name="add">
</body>
</html>
To get you started I made minor changes to your code, go through the changes and understand the use of each change.
function sum(){
var a = document.getElementById("a");
var b = document.getElementById("b");
alert(Number(a.value) + Number(b.value));
}
<!DOCTYPE html>
<html>
<head>
<title>TEST</title>
<script src= "script.js"> </script>
</head>
<body>
<h3> Calculator: </h3>
<input type="text" name="a" id="a">
<input type="text" name="b" id="b">
<input type="button" onClick="sum()" value="+" name="add">
</body>
</html>
Hey guys i put an alert box in to see if the code worked but when I ran it the code did not work. I tried debugging it and I think the issue is on document.getelementbyid (ofbat) but not sure exactly what is wrong there.
Also once the code works how do i add inner html to it so the answer comes out on the same screen? I emphasized the part where i thought the code was not working.
<html !doctype>
<html lang="en">
<head>
<meta charset="utf-8">
<title> Lab7 Baseball Form</title>
<script type="text/javascript">
function calculation() {
var batterName = parseFloat(document.getElementById('battername').value);
*var atBat = parseFloat(document.getElementById)('ofbat').value);*
var ofSingles = parseFloat(document.getElementById)('ofsingles').value);
var ofDoubles = parseFloat(document.getElementById)('ofdoubles').value);
var ofTriples = parseFloat(document.getElementById)('oftriples').value);
var ofHome = parseFloat(document.getElementById)('ofhome').value);
var totalBases = ofSingles *1 + ofDoubles * 2 + ofTriples * 3 + ofHome *4;
var slugPercent =totalBases/ atBat;
alert batterName + slugPercent;
}
</script>
</head>
<body>
<h1>Slugging Percentage Calculator</h1>
<form>
<p>Batter's Name:</p>
<input type="text" id="battername" /><br />
<p>Enter number of At Bats:</p>
<input type="text" id="ofbat" /><br />
<p>Enter number of Singles:</p>
<input type="text" id="ofsingles" /><br />
<p>Enter number of Doubles:</p>
<input type="text" id="ofdoubles" /><br />
<p>Enter number of Triples:</p>
<input type="text" id="oftriples" /><br />
<p>Enter number of Home Runs:</p>
<input type="text" id="ofhome" /><br />
<input type="button" value="Whats his slugging percentage?" onclick="calculation()">
</form>
</body>
</html>
You have syntax errors:
document.getElementById)('ofbat'): ) after Id. Same with all next lines.
alert is also a function so it should be called as alert(argument)
I think I found all syntax errors, if not let me know:
<html !doctype>
<html lang="en">
<head>
<meta charset="utf-8">
<title> Lab7 Baseball Form</title>
<script type="text/javascript">
function calculation() {
var batterName = parseFloat(document.getElementById('battername').value);
var atBat = parseFloat(document.getElementById('ofbat').value);
var ofSingles = parseFloat(document.getElementById('ofsingles').value);
var ofDoubles = parseFloat(document.getElementById('ofdoubles').value);
var ofTriples = parseFloat(document.getElementById('oftriples').value);
var ofHome = parseFloat(document.getElementById('ofhome').value);
var totalBases = ofSingles * 1 + ofDoubles * 2 + ofTriples * 3 + ofHome * 4;
var slugPercent = totalBases / atBat;
alert(batterName + slugPercent);
}
</script>
</head>
<body>
<h1>Slugging Percentage Calculator</h1>
<form>
<p>Batter's Name:</p>
<input type="text" id="battername" /><br />
<p>Enter number of At Bats:</p>
<input type="text" id="ofbat" /><br />
<p>Enter number of Singles:</p>
<input type="text" id="ofsingles" /><br />
<p>Enter number of Doubles:</p>
<input type="text" id="ofdoubles" /><br />
<p>Enter number of Triples:</p>
<input type="text" id="oftriples" /><br />
<p>Enter number of Home Runs:</p>
<input type="text" id="ofhome" /><br />
<input type="button" value="Whats his slugging percentage?" onclick="calculation()">
</form>
</body>
</html>
UPD: edited code some number of times because found one more syntax error. If you haven't seen this line, please check the code again.
I am absolutely new to javascript. I am trying to create my first html page and add some javascript on my html tags. I want to have two boxes where I can input any number and click on Show me! in order to get the result. I wrote the code below but is doesn't do anything:
<!DOCTYPE html>
<html>
<head>
<title>Interactive JS homework</title>
<style>
</style>
<script>
function calculate(){
var a = parseFloat(document.getElementById("a").value);
var b = parseFloat(document.getElementById("b").value);
document.getElementById("result") == a+b;
}
</script>
</head>
<body>
<form>
<p>
<input type="text" id="a" oninput="calculate();">
<input type="text" id="b" oninput="calculate();">
<input type="button" id="showme" value="Show me!" onclick="calculate();">
<input type="text" id="result">
</p>
</form>
</body>
Any help with where I am wrong?
Many thanks in advance!
You have to use the value property of the element. Please notice the changes in the operator used, it should be assignment (=) not compariosn (==).
document.getElementById("result").value = a+b;
I will also suggest you to assign 0 when there is no value in the element. This will prevent showing unexpected NaN as result if any of the element's value is empty.
<!DOCTYPE html>
<html>
<head>
<title>Interactive JS homework</title>
<style>
</style>
<script>
function calculate(){
var val1 = document.getElementById("a").value.trim();
var val2 = document.getElementById("b").value.trim();
var a = parseFloat(val1 == ""? 0 : val1);
var b = parseFloat(val2 == ""? 0 : val2);
document.getElementById("result").value = a+b;
}
</script>
</head>
<body>
<form>
<p>
<input type="text" id="a" oninput="calculate();">
<input type="text" id="b" oninput="calculate();">
<input type="button" id="showme" value="Show me!" onclick="calculate();">
<input type="text" id="result">
</p>
</form>
</body>
Well, it seems you merely forgot a little thing.
When reading the values of the a and b text boxes, you correctly used .value after retrieving the elements to access their value, but when you tried to set the value of result text box, you instead just compared it to the value of a+b. The == operator is for comparison, not setting a value.
Just as well, you will need to set the .value of the result text box, instead of the text box itself.
<!DOCTYPE html>
<html>
<head>
<title>Interactive JS homework</title>
<style>
</style>
<script>
function calculate(){
var a = parseFloat(document.getElementById("a").value);
var b = parseFloat(document.getElementById("b").value);
document.getElementById("result").value = a+b;
}
</script>
</head>
<body>
<form>
<p>
<input type="text" id="a" oninput="calculate();">
<input type="text" id="b" oninput="calculate();">
<input type="button" id="showme" value="Show me!" onclick="calculate();">
<input type="text" id="result">
</p>
</form>
</body>
<!DOCTYPE html>
<html>
<head>
<title>Function</title>
<script type="text/javascript">
function sum(x,y) {
var z = x+y;
document.write("Sum is"+z);
}
</script>
</head>
<body>
<form>
<input type="" id="t1" name=""/>
<input type="" id="t2" name=""/>
<input type="button" onclick="sum(t1.value,t2.value)" value="Click me"/>
</form>
</body>
</html>
Hi Guys, I am a beginner with JavaScript and I'm facing this little problem. If I enter 5 and 5 the result is 55. But I want to sum up these values.
As #TonyDong said, uses parseInt to convert the string to int if desired input is integer.
To make your function works better, you need to validate the inputs first before sum.
Below is one example:
make the type of two inputs are 'number'
checkValidity() for the form or two inputs in function=sum. if validated, sum the values, if not, return error.
<!DOCTYPE html>
<html>
<head>
<title>Function</title>
<script type="text/javascript">
function sum(x,y)
{
if(document.getElementById("submit").checkValidity()) {
var z = parseInt(x)+parseInt(y);
document.write("Sum is "+z);
}
else {
document.write("Input value must be Int!");
}
}
</script>
</head>
<body>
<form id="submit">
<input id="t1" name="" type="number"/>
<input id="t2" name="" type="number"/>
<input type="button" onclick="sum(t1.value,t2.value)" value="Click me"/>
</form>
</body>
</html>
You should covert x and y to integers first, like parseInt(x) and parseInt(y) while doing the summation.
Then, instead of document.write, you can use console.log.
<!DOCTYPE html>
<html>
<head>
<title>Function</title>
<script type="text/javascript">
function sum(x,y) {
var z = parseInt(x)+parseInt(y);
console.log("Sum is",z);
}
</script>
</head>
<body>
<form>
<input type="" id="t1" name=""/>
<input type="" id="t2" name=""/>
<input type="button" onclick="sum(t1.value,t2.value)" value="Click me"/>
</form>
</body>
</html>
I am newbie to Javascript... and I am unable to get from input to js variable, I referred to the questions asked here before still I unable to get the information. My code is as follows:-
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>JS </title>
<body>
<form>
<input type="text" id="amount" placeholder="Amount">
<button type="button" onclick="calc()">Submit</button>
</form>
<h1 id="TotalAmout"></h1>
<script>
function calc() {
var amt = document.getElementById("amount").value;
document.getElementById("TotalAmount").innerHTML = amt;
}
</script>
</body>
</html>
Typo in H1 TotalAmout should be TotalAmount
Calc should be defined before calling it. Fiddle
<head>
function calc() {
var amt = document.getElementById("amount").value;
document.getElementById("TotalAmount").innerHTML = amt;
}
</head>
<body>
<form>
<input type="text" id="amount" placeholder="Amount">
<button type="button" onclick="javascript:calc()">Submit</button>
</form>
<h1 id="TotalAmount"></h1>
</body>
You have a typo in your H1's ID. It should probably match the TotalAmount in your javascript.
Two things:
typo in "TotalAmout" and "TotalAmount"
function needs to be defined prior to calling it
see here: https://jsfiddle.net/zLguL6fu/:
<form>
<input type="text" id="amount" placeholder="Amount">
<button type="button" onclick="calc(); return false;">Submit</button>
</form>
<h1 id="TotalAmount"></h1>
function calc() {
var amt = document.getElementById("amount").value;
document.getElementById("TotalAmount").innerHTML = amt;
}
please use this code.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>JS </title>
<script src="//code.jquery.com/jquery-1.11.3.min.js"></script>
</head>
<body>
<form>
<input type="text" id="amount" placeholder="Amount">
<button type="button" onclick="calc()">Submit</button>
</form>
<h1 id="TotalAmout"></h1>
<script>
function calc() {
var amt = $("#amount").val();
$("#TotalAmout").html(amt);
}
</script>
</body>
</html>
and you also required add jquery js in head
<form>
<input type="text" id="amount" placeholder="Amount">
<button type="button" onclick="calc();return false">Submit</button>
</form>
<h1 id="TotalAmout"></h1>
<script>
function calc() {
var amt = $("#amount").val();
$("TotalAmount").html(amt);
}
</script>