node 的事件通知

var event_emitter = require('events').EventEmitter;
var event = new EventEmitter();

event.on('some_event' , function(){
                 console.log("haha");
                } ) ;

event.emit('some_event') ;

因為是異步架構  , 很適合在callback function裡面做呼叫function的動作.      

但是有個問題

當for(i = 0 ; i <100 ;i++) {
      get_web_data(url , callback());
}
此時get_web_data不能過於頻繁. 因為node主要是靠callback方式處理 , 此時node的缺點就會浮現. callback->function->callback.  程式邏輯就會支離破碎. node看來比較適合簡單的東西.

javascript 數組

var man = {name: "gary" , age:"30"};
man.name ->gary
delete man.age ->undefined


var man={};
man.name = peter;
mane; ->{name:peter}


var man = {"peter lin" : "man"  , 5: 10}
man["5"]; mane[2+3];  ->10
delete man["peter lin"]

var varname = "length";
var text="haha"
text[varname];   ->4

var haha ={};
haha.name = peter
"name" in haha -> true
"name" in haha.name ->true

function haha(value){
    var result = [];
    for(var i=0 ;i <=value;i++)
          result[i] = i;
    return result;
}
haha(4); ->[0,1,2,3,4]


var array=[];
array.push("haha");
array.push("make");
array.push("money");
array; ->["haha" ,"make","money"]
array.join[" "]; -> "haha make money"
array.pop();-> "money"
array; ->["haha","make"]

var word="haha make money"
word.split(" ");
->["haha","make","money"]


擷取字串
haha.slice(0,4)

range(1,10) ;

eclipse express terminated

 

Run

node.js eclipse break point

 

 

node.js eclipse 環境架設

1: eclipse-php-luna-SR2-win32-x86_64
2: node.js: http://www.nodeclipse.org/updates/
     vjet: http://download.eclipse.org/vjet/updates-0.10
     v8:  http://chromedevtools.googlecode.com/svn/update/dev/
    

 

  3: vjet 自動提示
      http://git.eclipse.org/c/vjet/org.eclipse.vjet.typelibs.git/commit/ 
      org.eclipse.vjet.typelibs-master.zip 
      透過eclipse    File->Import->General->Existing Projects into Workspace->Select archive file(選擇剛剛下的zip)選擇你想要的語言.
      
再設定下面屬性

 

  

3: express 安裝
npm install express-generator -g
express -h 確認是否安裝正確

 4:  supervisor
npm install -g supervisor

 
5: 全域變數設置,精簡路徑
//var time = require("./src/globalVar/systemVar.js");
var time = require("systemVar.js");

app.js按右鍵->Run as->Run configurations->Environment->New 變數