Converting Variables to Numbers


 

    There are 3 JavaScript methods that can be used to            convert variables to numbers:

  • The Number() method
  • The parseInt() method
  • The parseFloat() method

    These methods are not number methods, but global JavaScript methods.

    Global JavaScript Methods

    JavaScript global methods can be used on all JavaScript data types.

     


    These are the most relevant methods, when working with numbers :

    Number()  : Returns a number, converted from its argument.

    parseFloat() : Parses its argument and returns a floating point number.

    parseInt()  :  Parses its argument and returns an integer .

     

    try it in the console : 

    Number(10.34) ;       // returns 10.34

    parseFloat(2.56);      // returns   2.56  

    parseInt(2.56);         // returns   2

     

    in all above three methods :

    If the number cannot be converted, NaN (Not a Number) is returned. 

     

    " NaN is a JavaScript reserved word indicating that a number is not a legal number. "

     

     





    		  




    		  

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