In TypeScript, the Number.isFinite() method of the Number class is used to check if a certain number is
Note: TypeScript is the superset of JavaScript. Therefore, this method also exists in JavaScript.
Number.isFinite(number)
number: This is the number we want to check for finite values.
It returns true if the value is finite. Otherwise, it returns false.
// create some numbers in TypeScriptlet num1:number = 3224let num2:number = 0/0let num3:number = Number.POSITIVE_INFINITYlet num4:number = Number.NaNlet num5:number = 100// check if they are finiteconsole.log(Number.isFinite(num1)) // trueconsole.log(Number.isFinite(num2)) // falseconsole.log(Number.isFinite(num3)) // falseconsole.log(Number.isFinite(num4)) // falseconsole.log(Number.isFinite(num5)) // true
Lines 2–6: We use the number datatype to create and initialize a few variables.
Lines 4: The Number.POSITIVE_INFINITY property represents the positive infinity value. Its value is higher than any other number. It is a property of theNumber object.
Line 5: The Number.NaN property represents "Not-A-Number", meaning NaN is not a legal number. It returns true if the value's type is Number and NaN.
Lines 9–13: We use the Number.isFinite() method to check if the numbers are finite. We print the results to the console.
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