AS3 ByteArray to an object using depth copy

May 31 posted in Flash (RSS), comments.

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Use ActionScript3 new in ByteArray class (flash.utils.ByteArray) can create an object of deep copy. "Depth" means that you can copy an object (object) of all references, which means that if you copy an array containing an object, then the array of objects are copied (not quoted). Here is a clone method:

ActionScript Code  :

functionclone(source:Object):*{
var copier:ByteArray=newByteArray();
copier.writeObject(source);
copier.position=0;
return(copier.readObject());
}

Note: you need to import flash.utils.ByteArray;

To use this method, you can use the following code:

ActionScript Code:

newObjectCopy=clone(originalObject);

Although this method you can copy the depth of the object, but it will not copy with the class type definition. So, if Charlie need to copy a MyClass instance, copy the object will not be MyClass type. This method is best to use ordinary objects.

Here are some of my test code:

i

mportflash.utils.ByteArray;
flash.utils.getQualifiedClassName;
var a1:Array=[1,2,3];
var a2:Array=clone(a1);// Clone a1, a2 is saved in  a1 Of copies, and  a1 There is no relationship between the  
var a3:Array=a1;// Because of the a1 is an array  , So the a3 is a reference  a1
a1.push(4);// Change the value of the a1  
trace(a1);// Output  1,2,3,4
trace(a2);// Output  1,2,3
trace(a3);// Output  1,2,3,4
trace("===============");
varaa1:Array=[1,2,3];
varaa2:Array=[11,22,aa1]//aa2 An element is in the  aa1
varaa3:Array=clone(aa2);// Clone aa2, is saved in aa3  aa2 A copy, of aa2  aa1 Also copies  
trace(aa1);// Output  1,2,3
trace(aa2);// Output  11,22,1,2,3
aa1.push(4);// Modify the value of aa1  
trace(aa2);// Output  11,22,1,2,3,4
trace(aa3);// Output  11,22,1,2,3
trace(getQualifiedClassName(aa2));// Output  Array
trace(getQualifiedClassName(aa3));// Output Array, this description  Array You can maintain a clone of a clone of the result Array type invariant  
trace("===============");
var aaa1:MyClass=newMyClass();// Build a custom type  
var aaa2=clone(aaa1);// Clone custom types  
trace(aaa2.a);// Output  1
trace(getQualifiedClassName(aaa2));// This indicates that the output Object,  aaa2 The type of MyClass lost

functionclone($source:Object):*
{
var _copier:ByteArray=newByteArray();
_copier.writeObject($source);
_copier.position=0;
return_copier.readObject();
}

MyClass.as content

package{
public class MyClass{
public var a:int=1;
public var b:int=2;
public function MyClass(){}
}
}

Note:
Can not be cast for the aaa2 type, if you use the following statement:

var aaa2=MyClass(clone(aaa1));
 It is an error  :

TypeError:Error#1034: Cast type failed  : Cannot add  Object@138c0341 Converted to  MyClass.
atDeepObjectCopieswithByteArray_fla::MainTimeline/DeepObjectCopieswithByteArray_fla::frame1()
 If you use the convert statement as  , The resulting value is aaa2  null.