Node.js
iii
7. Event Loop .............................................................................................................................................. 23
Event-Driven Programming ........................................................................................................................... 23
Example ......................................................................................................................................................... 24
How Node Applications Work? ..................................................................................................................... 25
8. Event Emitter .......................................................................................................................................... 26
EventEmitter Class ......................................................................................................................................... 26
Methods ........................................................................................................................................................ 26
Class Methods ............................................................................................................................................... 27
Events ............................................................................................................................................................ 28
Example ......................................................................................................................................................... 28
9. Buffers .................................................................................................................................................... 30
Creating Buffers ............................................................................................................................................. 30
Writing to Buffers .......................................................................................................................................... 30
Reading from Buffers ..................................................................................................................................... 31
Convert Buffer to JSON .................................................................................................................................. 32
Concatenate Buffers ...................................................................................................................................... 33
Compare Buffers ............................................................................................................................................ 33
Copy Buffer .................................................................................................................................................... 34
Slice Buffer ..................................................................................................................................................... 35
Buffer Length ................................................................................................................................................. 36
Methods Reference ....................................................................................................................................... 36
Class Methods ............................................................................................................................................... 41
10. Streams ................................................................................................................................................... 43
What are Streams? ........................................................................................................................................ 43
Reading from a Stream .................................................................................................................................. 43
Writing to a Stream ....................................................................................................................................... 44
Piping the Streams ......................................................................................................................................... 45
Chaining the Streams..................................................................................................................................... 46
11. File System .............................................................................................................................................. 48
Synchronous vs Asynchronous ...................................................................................................................... 48
Open a File ..................................................................................................................................................... 49
Get File Information ...................................................................................................................................... 51
Writing a File ................................................................................................................................................. 53
Reading a File................................................................................................................................................. 54
Closing a File .................................................................................................................................................. 56
Truncate a File ............................................................................................................................................... 57
Delete a File ................................................................................................................................................... 59
Create a Directory ......................................................................................................................................... 60
Read a Directory ............................................................................................................................................ 61
Remove a Directory ....................................................................................................................................... 62
Methods Reference ....................................................................................................................................... 63
12. Global Objects ........................................................................................................................................ 69
__filename ..................................................................................................................................................... 69
__dirname ..................................................................................................................................................... 69
setTimeout(cb, ms) ........................................................................................................................................ 70
clearTimeout (t) ............................................................................................................................................. 70
setInterval(cb, ms) ......................................................................................................................................... 71
Global Objects ............................................................................................................................................... 71
