Basic Class Library ​

1. console ​

The console.log method is used to output information in the console window. It can accept multiple parameters and connect their results to output.

2. Math ​

Properties ​

  • E
  • LN10
  • LN2
  • LOG2E
  • LOG10E
  • PI
  • SQRT1_2
  • SQRT2
For the specific use of the above properties, please refer to the ES5 standard.

Method ​

  • abs
  • acos
  • asin
  • atan
  • atan2
  • ceil
  • cos
  • exp
  • floor
  • log
  • max
  • min
  • pow
  • random
  • round
  • sin
  • sqrt
  • tan
For the specific use of the above properties, please refer to the ES5 standard.

3. JSON ​

Method ​

  • stringify(object): Convert the object object to a JSON string and return the string.

  • parse(string): Convert the JSON string to an object and return the object.

Sample code:

js
console.log(undefined === JSON.stringify());
console.log(undefined === JSON.stringify(undefined));
console.log("null"===JSON.stringify(null));

console.log("111"===JSON.stringify(111));
console.log('"111"'===JSON.stringify("111"));
console.log("true"===JSON.stringify(true));
console.log(undefined===JSON.stringify(function(){}));


console.log(undefined===JSON.parse(JSON.stringify()));
console.log(undefined===JSON.parse(JSON.stringify(undefined)));
console.log(null===JSON.parse(JSON.stringify(null)));

console.log(111===JSON.parse(JSON.stringify(111)));
console.log("111"===JSON.parse(JSON.stringify("111")));
console.log(true===JSON.parse(JSON.stringify(true)));

console.log(undefined===JSON.parse(JSON.stringify(function(){})));

4. Number ​

Properties ​

  • MAX_VALUE
  • MIN_VALUE
  • NEGATIVE_INFINITY
  • POSITIVE_INFINITY
For the specific use of the above properties, please refer to the ES5 standard.

5. Date ​

Properties ​

  • parse
  • UTC
  • now
For the specific use of the above properties, please refer to the ES5 standard.

6. Global ​

Properties ​

  • NaN
  • Infinity
  • undefined
For the specific use of the above properties, please refer to the ES5 standard.

Method ​

  • parseInt
  • parseFloat
  • isNaN
  • isFinite
  • decodeURI
  • decodeURIComponent
  • encodeURI
  • encodeURIComponent
For the specific use of the above properties, please refer to the ES5 standard.