what you don"t understand, as shown in the figure:
this is the initialization property pair method that will be performed when instantiated. Why do you need to make a judgment on the attribute? Please let me know
I slightly modified the problem, changing the module source links and screenshots to his v1.0.0 version. This version is more simplified
I think it's because any instance of EventEmitter can execute event.prototype.init,. If an existing event executes the init method, it needs to be judged by IF
No usefulness is found in this version. the following is a wild guess .
if (!this._events ...){
} this part may be historical legacy code, which means if it looks like a duck, swims like a duck, and sounds like a duck, then it is most likely a duck , so it is not re-instantiated. it is recommended to check the historical version and how it is used .
this._maxListeners = this._maxListeners || undefined; if this._maxListeners is false, it becomes undefined , such as 0/NaN .
var http = require("http") var server = http.createServer(function(req,res){ console.log("jirengu") res.setHeader("Content-Type","text plain";"charset=gbk") res.write( <h1>jirengu<...
sincerely ask for advice: < hr > I want to use node as the background to build a video streaming server. The front end is similar to Youku VOD. It can record the playback node function, and load the progress bar at any point (starting from the c...
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var http = require("http") var server = http.createServer(function(req,res){ console.log("hello") console.log(2222) res.setHeader("Content-Type","text html","charset=gbk") res.write( <...
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adopt a reward of 10 yuan, 1045 Access denied for user root @ localhost (using password:NO) recently, when I was at the front end of my self-study, I came into contact with a little bit of database. This happened when I made a new connection on ...
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Please recommend the library reported by error monitoring at the front end, or post relevant codes the discovery written by myself is not comprehensive, unable to listen for resource errors, but can only listen for run-time errors. I don t know if th...
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like this [array [xxx], array [xxx], array [xxx].] merge all xxx in array into one array [xxx.] ...