javascript

How objects in js are declared and some usage examples for arrays


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<script>
//Define a print function
var $=function(str){
document.write(str);
document.write("<br/>");
}
//Defines the print array function
var _=function(arr){
for(var tmp in arr)
{
$(arr[tmp]);
}
}
//Define a student object
var stu=new Object();

//Declare properties and behaviors
stu.id=16;
stu.name=' Light currency ';
stu.age=function(){
return this.id;
}

//Print student information
$(stu.id);
$(stu.name);
$(stu.age());//Call with parentheses

stu.sex=' female '; //Add a new property
$(stu.sex); //Print the newly added properties

//Scheme 2:
function Student(id,name)
{
this.id=id;
this.name=name;
this.getAge=function(){
return this.id;
}

}

// use
var stu2=new Student(1,' Yang, ');
$(stu2.id);
$(stu2.name);
$(stu2.getAge());
//Define one more property
stu2.sex=' transsexuals ';
$(stu2.sex);
//How do dynamic languages cross domains?
Student.prototype.address=" Afghanistan ";
$(stu2.address);
$("stu2_1 begin...");
var stu2_1 =new Student(1,' Yang, ');
$(stu2_1.id);
$(stu2_1.name);
$(stu2_1.getAge());
$(stu2_1.sex);
$(stu2_1.address); //Cross-domain access, b objects access the properties of a objects
//In the definition
$("stu2_1 end...");

//Scenario 3: json
var stu3={id:1,name:' Mao Yanyan ',getName:function(){return this.name;}};
$(stu3.id);
$(stu3.name);
$(stu3.getName());

//var stu2

//Many functions in js have the same name as functions in Java
var str1=new String("abcd")
var str2="asdf";
$(str1.indexOf('c'));
$(str1.charAt(3));
$ (str2.charAt(3));
$("absdf".substring(2,4));

var day=new Date();
$(day.getYear());
$(day.toLocaleString());


//Talk about an array
var arr1=new Array(3);
arr1[0]=10;
arr1[1]=20;
arr1[2]=3;
_(arr1);
arr1[3]=4;
//
_(arr1);

//An array of 2
var arr2=new Array(234,345,2354,2134,234);
_(arr2);

//An array of 3
var arr3=new Array();
arr3[0]=10;
arr3[1]=20;
arr3[2]=3;
_(arr3);

//Array 4. Recommended writing
var arr4=[];
arr4[0]=10;
arr4[1]=20;
arr4[2]=3;
_(arr4);

//Array 5. Recommended writing
var arr5=[3254,43,532,45,2345];
_(arr5);

function add(i,j){
return i+j;
}

function add(i,j,k){
return i+j+k;
}

$(add(1,2));//Automatically identify the number of parameters

var Person=function(id,name)
{
this.id=id;//public
this.name=name;//public
var i=1;//private
function test(){//private
alert('asdf');
}
this.t=function()//public
{
return 1;
}
}
var p=new Person(1," Chen xin ");
$(p.id);
$(p.name);
$(p.t());//Normal access
$(p.test()); //Can not access
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