Reputation: 33
How to set auto 2 decimal number using value from id input type="text"
javascript ?
First , fill data eg: 2
into input , it's will update input to 2.00
But not work When i user this
var numb = document.getElementById("int").value;
How can i do ? thank.
<script type="text/javascript" src="http://code.jquery.com/jquery-1.8.3.js"></script>
<script type="text/javascript">
function fn_do() {
var numb = document.getElementById("int").value;
//var numb = 123;
var zzz = numb.toFixed(2);
document.getElementById("int").value = zzz;
}
</script>
<input type="text" id="int" onchange="fn_do()">
Upvotes: 0
Views: 5311
Reputation: 2168
If I'm understanding this correctly, you want whatever number is put into the object with the id 'int' to be automatically converted to a decimal value with two placeholders. You could do something like this:
function convertToDecimal(value) {
var tempValue = Nath.Round(parseFloat(value) * 100);
var returnValue = tempValue * .01;
return returnValue;
}
That would ensure that you always get two decimal places
Exceptions: 1. if tempValue is a multiple of 10, only one decimal will come out 2. if tempValue is a multiple of 100, no decimals will be returned
Solution:
function convertDecimals(convertedValue) {
var tempValue = Nath.Round(parseFloat(value) * 100);
if ((tempValue % 10) == 0) {
if ((tempValue % 100) == 0) { var returnValue = convertedValue + .00; return returnValue; } else {
var returnValue = convertedValue + 0;
return returnValue;
}
}
return '';
}
So maybe the whole cde would look like this
function fn_do() {
var numb = document.getElementById("int").value;
//var numb = 123;
var zzz = convertToDecimal(numb);
zzz = zzz + convertDecimal(zzz);
document.getElementById("int").value = zzz;
}
function convertToDecimal(value) {
var tempValue = Nath.Round(parseFloat(value) * 100);
var returnValue = tempValue * .01;
return returnValue;
}
function convertDecimals(convertedValue) {
var tempValue = Nath.Round(parseFloat(value) * 100);
if ((tempValue % 10) == 0) {
if ((tempValue % 100) == 0) { var returnValue = convertedValue + .00; return returnValue; } else {
var returnValue = convertedValue + 0;
return returnValue;
}
}
return '';
}
Upvotes: 0
Reputation: 13848
You should use parseFloat
, because DOM property value
is a string, not number.
var zzz = parseFloat(numb).toFixed(2)
And don't use parseInt
, because it'll give you an integer, for example parseInt("1.2")
will be 1
, then toFixed(2)
gives you 1.00
, while you actually want 1.20
I assume.
One more thing to care is, make sure input content is valid, for example parseFloat('qwer')
will give you NaN
. So the final code would look like:
var zzz = (parseFloat(numb) || 0).toFixed(2);
Upvotes: 2
Reputation: 18873
Instead of
var zzz = numb.toFixed(2)
Try
var zzz = parseFloat(numb).toFixed(2) //use parseInt() or parsFloat() as shown here.
Your complete will look like this :-
function fn_do() {
var numb = document.getElementById("int").value;
var zz = parseFloat(numb) || 0; //it will convert numb to float if conversion fails it will return 0.
var zzz = zz.toFixed(2);
document.getElementById("int").value = zzz;
}
Upvotes: 2
Reputation: 706
var decimalForm = parseFloat(Math.round( intNum * 100) / 100).toFixed(2);
alert(decimalForm );
Upvotes: 0