isFinite( )

 

 


 

 

isFinite( );

this built in function is used to check if the data Numerical value or String value .

isFinite( ) :  Check if a number is finite .

isFinite( ) : return true or false depending on the argument. 

 

The isFinite() method returns true if a value is a finite number.

Infinite (not finite) values are Infinity, -Infinity, or NaN

 

for example :

isFinite(170538);      \\ return true

isFinite("189anbz46");   \\ return false

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