JavaScript Learning Notes

1, the = = = operator compares the value of two objects to the type of!==.

Cases:

var i = 0;var j = ' 0 '; I ==j//Truei = = = J//False

2. Events

<DivID= ' Test '>    <ButtonID= "BTN"/>
<a href= "www.baidu.com" id= "BD" > Baidu </a></Div><Script>document.getElementById ('btn'). AddEventListener ('Click', Demo1); document.getElementById ('b'). AddEventListener ('Click', Demo2);

    document.getElementById (' BD '). AddEventListener (' click ', Demo3);

 function   Demo1 (e) {alert ( "  test1   " ); 
//e.stoppropagation ();//block event bubbling}  function   Demo2 () {alert ( "  test2   " );} 
  

function Demo3 (e) {     alert (' test3 ');
　　  E.preventdefault ();//block default behavior}    

</ Script >

When the button is clicked, event bubbling occurs, so the event is executed from the bottom up, that is, Button-->div.

The result is: Eject test1 first, then eject Test2.

Block event bubbling: Using E.stoppropagation ();

3. How to create objects

<!-- Creating Objects  -     /* Method One *    /people = new Object ();    People.age =;    People.name = ' Baohua ';    document.write (' Name: ' +people.name+ ' Age: ' +people.age ');    /* Method Two */    animal = {Age        : $  ,        type: ' Dog ',        voice:function () {        alert (' Brak ');    }    };    Document.writeln (' Animal type: ' +animal.type+ ' animal Age: ' +animal.age ');    Animal.voice ();    /* Method Three    *  /function Plant (type,name) {        this.type = type;        this.name = name;    }    Flower = new Plant (' flower ', ' rose ');    Document.writeln ("Plant type:" +flower.type+ "Plant Name:" +flower.name ");

JavaScript Learning Notes