javascript-basic/2-02.Number.html at main · kimyh1207/javascript-basic · GitHub

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<!DOCTYPE html>
<html>
<head>
  <title>Document</title>
</head>
<body>
  <script>
    //Number

    var x = 123;
    //toString();
    console.log(x.toString());

    //toFixed()
    //지정된 소수점 자리수까지 반올림으로 표기
    var x = 123999.567243;
    console.log(x.toFixed(2));

    //toPrecision()
    var x = 9.545;
    console.log(x.toPrecision(2));

    var x = Number("10"); // 숫자 10
    var x = Number(true); //1
    var x = Number(false); //0
    console.log(Number(" 10  "));
    console.log(Number("3.14"));
    console.log(Number(" 10"));
    console.log(Number(" 10.33"));
    console.log(Number(" 10,33")); //NaN
    console.log(Number("John")); //NaN
    console.log(Number("10 33")); //NaN
    //NaN - Not a Number

    //parseInt()
    console.log(parseInt("3"));
    console.log(parseInt("3.9"));
    console.log(parseInt("10 33"));
    console.log(parseInt("12 years"));
    console.log(parseInt("years 13"));

    //parseFloat()
    console.log(parseFloat("10"));
    console.log(parseFloat("13.9"));
    console.log(parseFloat("13.9 aa"));


  </script>
</body>
</html>