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I'm trying to convert req.params to Number because that is what I defined in my schema for year param.
I have tried
req.params.year = parseInt( req.params.year, 10 ); and
Number( req.params.year); and
1*req.params.year; but non of them works. Do I need to install something?
426
You convert a string to a number by calling the Parse or TryParse method found on numeric types ( int , long , double , and so on), or by using methods in the System. Convert class. It's slightly more efficient and straightforward to call a TryParse method (for example, int.
How to convert a string to a number in JavaScript using the unary plus operator ( + ) The unary plus operator ( + ) will convert a string into a number. The operator will go before the operand. We can also use the unary plus operator ( + ) to convert a string into a floating point number.
How do I convert a string to a number in react? We can make use of the Number object to convert a string to a number. const amount = Number(inputValue); const convenienceFee = Number('20'); const inputValue : string = "250" const amount : number = Number(inputValue);
The parseFloat() function is used to accept the string and convert it into a floating-point number. If the string does not contain a numeral value or If the first character of the string is not a Number then it returns NaN i.e, not a number.
You do not have to install something.
parseInt(req.params.year, 10); should work properly.
console.log(typeof parseInt(req.params.year)); // returns 'number' What is your output, if you use parseInt? is it still a string?
101
Using parseInt() is a bad idea mainly because it never fails. Also because some results can be unexpected, like in the case of INFINITY.
Below is the function for handling unexpected behaviour.
function cleanInt(x) { x = Number(x); return x >= 0 ? Math.floor(x) : Math.ceil(x); } See results of below test cases.
console.log("CleanInt: ", cleanInt('xyz'), " ParseInt: ", parseInt('xyz')); console.log("CleanInt: ", cleanInt('123abc'), " ParseInt: ", parseInt('123abc')); console.log("CleanInt: ", cleanInt('234'), " ParseInt: ", parseInt('234')); console.log("CleanInt: ", cleanInt('-679'), " ParseInt: ", parseInt('-679')); console.log("CleanInt: ", cleanInt('897.0998'), " ParseInt: ", parseInt('897.0998')); console.log("CleanInt: ", cleanInt('Infinity'), " ParseInt: ", parseInt('Infinity')); result:
CleanInt: NaN ParseInt: NaN CleanInt: NaN ParseInt: 123 CleanInt: 234 ParseInt: 234 CleanInt: -679 ParseInt: -679 CleanInt: 897 ParseInt: 897 CleanInt: Infinity ParseInt: NaN If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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