file.js 1.2 KB

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  1. // ES6
  2. let a = () => alert("Hello");
  3. let cube = (x) => x**3;
  4. let avg2 = (a,b) => (a+b)/2;
  5. let sum3 = (a,b,c) => (a+b+c) || (a+b);
  6. let intRandom = (a,b) => { if(b === undefined){
  7. c = (Math.round(Math.random() *a))
  8. } else
  9. c = (Math.round(Math.random() * (b - a) + a));
  10. return c
  11. };
  12. let greetAll = (...params) =>{
  13. let guys = '';
  14. for(i = 0;i<params.length;i++){
  15. guys+= "," + " " + params[i]
  16. }
  17. alert(`Hi ${guys}`)
  18. };
  19. let sum = (...params) =>{
  20. let result = 0;
  21. for(i = 0;i<params.length;i++){
  22. result += params[i]};
  23. return result
  24. };
  25. // array map
  26. let arr = ["1", {}, null, undefined, "500", 700]
  27. arr.map(x => typeof(x) === 'string'? parseInt(x): x)
  28. // array reduce
  29. let arr1 = ["0", 5, 3, "string", null]
  30. arr1.reduce( (a,b) => {
  31. if(typeof(a) === 'number'){
  32. a = a
  33. }else{
  34. a = 1
  35. }
  36. if(typeof(b) === 'number'){
  37. b = b
  38. }else{
  39. b = 1
  40. }
  41. return a*b
  42. }
  43. )
  44. // object filter
  45. let phone = {
  46. brand: "meizu",
  47. model: "m2",
  48. ram: 2,
  49. color: "black",
  50. };
  51. let objFilter = (object,keys,value) => {
  52. for(let key in object){
  53. if(key != keys && object[key] !=value)
  54. delete object[key];
  55. }
  56. return object
  57. }