JavaScript var not being recognized as a number - Stack Overflow

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I have an HTML div, which I use JavaScript to retrieve the value from, as below:

    var oCreditStatus = document.getElementById('creditStatusField');

    var oOrigValue = oCreditStatus.value;

var oOrigValue will always be a number, and sometimes 0 (Zero).

I now want to increment or decrement the number by 1. However, when I do the following:

var oNewValue = oCreditStatus.value + 1;

I get the value 01, then 011, which is wrong as I want 1,2.

I know it is not recognizing it as a number, but how do I get it to do so.

I have an HTML div, which I use JavaScript to retrieve the value from, as below:

    var oCreditStatus = document.getElementById('creditStatusField');

    var oOrigValue = oCreditStatus.value;

var oOrigValue will always be a number, and sometimes 0 (Zero).

I now want to increment or decrement the number by 1. However, when I do the following:

var oNewValue = oCreditStatus.value + 1;

I get the value 01, then 011, which is wrong as I want 1,2.

I know it is not recognizing it as a number, but how do I get it to do so.

• javascript
• var

Share Improve this question Follow asked Jan 19, 2015 at 15:03 AlexAlex 4,0181010 gold badges5151 silver badges100100 bronze badges 5

• 4 oCreditStatus's value is stored as a string. You will need to convert it to a number before adding with it: var oOrigValu = Number(oCreditStatus.value) – ndugger Commented Jan 19, 2015 at 15:04
• 1 You may also use: var oNewValue = +oCreditStatus.value + 1; – Bhojendra Rauniyar Commented Jan 19, 2015 at 15:07
• possible duplicate of How to make a document.getElementById value into an integer variable, not a string? – James Thorpe Commented Jan 19, 2015 at 15:10
• There is absolutely nothing wrong with this question and no reason to mark it down. Anyone who ever voted down, do you wish to explain your reasons? @JamesThorpe ? – Alex Commented Jan 19, 2015 at 15:18
• @Alex I didn't downvote it - that was someone else. Just pointed out the potential duplicate. – James Thorpe Commented Jan 19, 2015 at 15:19

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5 Answers 5

Sorted by: Reset to default 5

You can't. Javascript engine will read it as a text/string. You've to use following code:

Edit. Use a radix (base 10) Thanks to @James for revision.

var oCreditStatus = document.getElementById('creditStatusField');

var oOrigValue = parseInt(oCreditStatus.value, 10); // use parseFloat for decimal.

var oOrigValue will always be a number, and sometimes 0 (Zero).

Just pass it to Number function since oOrigValue is always a number. (Note: 0 is also a number)

var oOrigValue = Number(oCreditStatus.value);

There are several other ways of doing the same by prefixing it with + and ~~

In fact oOrigValue is not a number, it's a string. To be able to add another number to it, you'll have to parse it first. There is several methods to do it:

var parsedValue = parseInt(oOrigValue, 10); // remember about the second parameter - the radix

or simpler, but less readable

var parsedValue = +oOrigValue;

try to this

var oCreditStatus = document.getElementById('creditStatusField').value*1;

You need to parse oCreditStatus.value as an int

var oNewValue = parseInt(oCreditStatus.value) + 1;

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