JavaScript Mapping Library
Every once in a while I learn about a JavaScript property that I wish I had known about years earlier — valueAsNumber is one of them. The valueAsNumber provides the value of an input[type=number] as a Number type, instead of the traditional string representation when you get the value:
valueAsNumber
input[type=number]
/* Assuming an <input type="number" value="1.234" /> */ // BAD: Get the value and convert the number input.value // "1.234" const numberValue = parseFloat(input.value, 10); // GOOD: Use valueAsNumber input.valueAsNumber // 1.234
This property allows us to avoid parseInt/parseFloat, but one gotcha with valueAsNumber is that it will return NaN if the input is empty.
parseInt
parseFloat
NaN
input
Thank you to Steve Sewell for making me aware of valueAsNumber!
PSA: number inputs have a `.valueAsNumber` property that you may find handy pic.twitter.com/1QwdAW16CC — Steve Sewell (@Steve8708) March 31, 2022
PSA: number inputs have a `.valueAsNumber` property that you may find handy pic.twitter.com/1QwdAW16CC
— Steve Sewell (@Steve8708) March 31, 2022
The post Input valueAsNumber appeared first on David Walsh Blog.
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