Learn with quizes about the JavaScript grammar

Transcript

1. Learn with quizes about the JavaScript grammar k-kuwahara @kuwahara_jsri @clown0082 Oct 2, 2018 ʲαϙʔλʔζCoLabษڧձʳ
2. About me const my_info = { Workplace: ‘Yumemi Inc’, Community: ‘Riot.js, Ionic, Dist’, Favorites: ‘CLI made by Node.js’, PokemonGO: ‘TL38’ }
3. github.com/riot
4. Sorry... " Because of time, I don’t mention all the grammar of JavaScript.
5. ⚠Attention⚠ We verified this slide with Google Chrome. Please check other browsers by yourself.
6. History of JavaScript Quiz about the “scope” Quiz about the “closure” Quiz about the “this" Agenda
7. History of JavaScript
8. See this page https://qiita.com/a_rcsin/items/0a3c8c98c8d703c49a22 or See this slide https://qiita.com/Mic-U/items/c900a6f62862954d62e0
9. Quiz about the “scope”
10. There are three scopes in JavaScript
11. global local block Variable declared at top level Variables declared in functions Variable declared in {}(block) Available from anywhere in the program Can be referenced only in functions Only available within {}(block)
12. Question 1
14. Answer
16. Question 2
18. Answer
20. Question 3
22. Answer
24. BTW,
26. Answer 1
28. Answer 2
30. Question 4
31. “window” is a global objects.
32. Answer
34. Question5
36. Answer
38. Quiz about the “closures”
39. in advance…
40. We can refer to the variable defined by the parent function
41. Lexical scope
42. Based on this…
44. define from outer function “init” Function “init” is a function that returns a function
45. Question 1
47. Answer
49. Question 2
51. Answer
53. Practical example code by: http://dqn.sakusakutto.jp/2012/02/javascript_13.html
54. using jQuery
55. Reference http://dqn.sakusakutto.jp/2009/01/javascript.html
56. Quiz about the “this”
57. “this” is also called a “context”.
58. There are several contexts
59. global function window objects bind methods arrow function methods of objects prototype chain
60. Question 1
62. Answer
64. BTW,
66. Question 2
68. Answer
70. Question 3
71. arrow function
72. Answer
74. Question 4
76. Answer
78. Have a nice JavaScript life!!
79. Publicity
80. We’re looking for Engineers!!