actionscript:未定义的公共变量？

Question

我有这样的课..

public class Doc {
  public function Doc():void {}

  public var myVar:Boolean;
}

我如何知道myVar持有的值是否为默认值,或者某人是否为其分配了错误？!？是不是有未定义的状态？我怎么能做到这样的事情？

Answer 1

使myVar成为属性并使用另一个变量来检查它是否已显式设置.

public class Doc 
{
  public function Doc():void {}

  private var _myVar:Boolean;
  private var myVarSetExplicitly:Boolean = false;
  public function get myVar():Boolean
  {
    return _myVar;
  }
  public function set myVar(value:Boolean):void
  {
    myVarSetExplicitly = true;
    _myVar = value;
  }
}