AS3中对象的深度复制

复制复杂对象（例如ArrayCollection,XML）时，可以使用ObjectUtil.copy()方法，代码如下：

 

//Object对象：

var obj1:Object = {name:"name01",data:"data01"};
var obj2:Object = ObjectUtil.copy(obj1);
obj2.name = "name02";
obj2.data = "data02";
ArrayCollection：
var ac2:ArrayCollection = ObjectUtil.copy(ac) as ArrayCollection;

//XML：

var myXML2:XML = ObjectUtil.copy(myXML1) as XML;

 

 因为copy方法返回的结果是Object类型，如果对于自定义的对象，copy方法返回结果类型就会丢失，变成Object，而且无法转换成自定义的对象，我们需要对ObjectUtil.copy()方法进行修改，让他支持自定义的类型。

源码如下：

 

public static function copy(value:Object):Object
    {
        var buffer:ByteArray = new ByteArray();
        buffer.writeObject(value);
        buffer.position = 0;
        var result:Object = buffer.readObject();
        return result;
    }

 

 所做修改如下：

 

import flash.utils.ByteArray;
import flash.utils.getQualifiedClassName;
import flash.net.*;
import src.*;

function cloneObject(source:Object) :* {
    var typeName:String = getQualifiedClassName(source);//获取全名
    trace(”输出类的结构”+typeName);
    //return;
    var packageName:String = typeName.split(”::”)[0];//切出包名
    trace(”类的名称”+packageName);
    var type:Class = getDefinitionByName(typeName) as Class;//获取Class
    trace(type);
    registerClassAlias(packageName, type);//注册Class
    //复制对象
    var copier:ByteArray = new ByteArray();
    copier.writeObject(source);
    copier.position = 0;
    return copier.readObject();
}

 

 有的人说用复制对象那一段不就可以了吗，但是实际上行不通。对于数组深度复制来说， 复制对象的后面4句代码就足够了。

 

var a1:Array=[1,2,3];
var a2:Array =cloneObject(a1);
var a3:Array = a1;
a1.push(”youmila”);
trace(”a1:”+a1+”a2:”+a2+”a3″+a3);

 

 但是对于对象来说肯定不行，用列子测试下，src.youmila.as 代码： 

 

package src{

public class youmila{
    private var $_name:String =”youmila”;
    private var $_num:Number =0;
    public function youmila():void{
    trace($_name);
}

public function secondFunc():void{
    $_num++;
    trace(”this a called function $_num::”+$_num);
}
}
}

 

 yapollo.as 代码： 

 

package {

public class yapollo{
    private var $_name:String =”yapollo”;
    public var $_num:Number =0;
    public function yapollo():void{
    trace($_name);
}

public function secondFunc():void{
    $_num++;
    trace(”this a called function $_num::”+$_num);
}
}
}

 测试实例: 

 

var uml1:youmila = new youmila();
var uml2 = cloneObject(uml1);
trace(”类型”+getQualifiedClassName(uml2));

 输出结果： 

 

youmila

类型Object

 

原来的对象类型丢失了，所以对于对象而言，四行不够，必须用registerClassAlias来保存类的别名，以用于丢失后恢复类的类型，测试实例: 

 

var uml1:youmila = new youmila();
var uml2 = cloneObject(uml1);
trace(”类型”+getQualifiedClassName(uml2));
var apollo:yapollo = new yapollo();
apollo.secondFunc();
var apollo2 = cloneObject(apollo);
trace(”第一次输出复制对象的$_num值”+apollo2.$_num);
trace(”类型”+getQualifiedClassName(apollo2));
apollo2.secondFunc();
trace(”第二次输出复制对象的$_num值”+apollo2.$_num);

 输出结果： 

 

youmila

输出类的结构src::youmila

类的名称src

[class youmila]

youmila

类型src::youmila

yapollo

this a called function $_num::1

输出类的结构yapollo

类的名称yapollo

[class yapollo]

yapollo

第一次输出复制对象的$_num值1

类型yapollo

this a called function $_num::2

第二次输出复制对象的$_num值2