angular - How to convert a number to double data type in javascript typescript? - Stack Overflow

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I have one input filed where the user can enter any numbers eg: 12 12.1 12.30 12.34 I have to pass this value in a service call here i can only send the value as number but with 2 decimal points

let a = input //a will be a type of number
let b = a.toFixed(2) //b will be type of string
let c = Number(b) //it will automatically cut unwanted '0'
console.log(c);

EXAMPLE

//input is 12
a=12
b="12.00"
c=12

//input is 12.30
a=12.30
b="12.30"
c=12.3

I want a method, using which i can input a value as a number and output will be number with 2 decimal points.

I have one input filed where the user can enter any numbers eg: 12 12.1 12.30 12.34 I have to pass this value in a service call here i can only send the value as number but with 2 decimal points

let a = input //a will be a type of number
let b = a.toFixed(2) //b will be type of string
let c = Number(b) //it will automatically cut unwanted '0'
console.log(c);

EXAMPLE

//input is 12
a=12
b="12.00"
c=12

//input is 12.30
a=12.30
b="12.30"
c=12.3

I want a method, using which i can input a value as a number and output will be number with 2 decimal points.

• javascript
• angular
• typescript

Share Improve this question Follow asked Jul 28, 2017 at 21:35 Aswin KVAswin KV 1,76022 gold badges1414 silver badges2424 bronze badges 4

• 3 All numeric types in typescript are number which are floating point values, so I don't think data type conversion is what you're after here. Seems like you just want to take any number and round/truncate it or right-pad w/ zeroes to two digits. typescriptlang/docs/handbook/basic-types.html – JBC Commented Jul 28, 2017 at 21:40
• 2 You can try getting the value of your input, parseFloat it and then toFixed it – Lixus Commented Jul 28, 2017 at 21:42
• "Double" does not mean two decimal places, it means double precision. There is no way to specify a number to a fixed number of places except to store it as a string using .toFixed. That's the whole reason that method returns a string in the first place. – Jared Smith Commented Jul 28, 2017 at 21:49
• Actually, you may want to use toExponential method, so you can store your 12.30 number as 1230e-2 and don't loose that zero. – Maxim Mazurok Commented Jul 28, 2017 at 21:56

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1 Answer 1

Sorted by: Reset to default 2

If you want a number to always display in two decimal places, you can do as below. It will round all the numbers to two decimal places(including doubles).

function twoDecimal(yourNumber){
    return parseFloat(Math.round(yourNumber * 100) / 100).toFixed(2);
}

let x=twoDecimal(10);

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