检查对象是否为空

如果你的意思是,如果一个对象没有属性:

var isEmpty:Boolean = true;
for (var n in obj) { isEmpty = false; break; }

Object.prototype.isEmpty = function():Boolean {
    for(var i in this)
        if(i != "isEmpty")
            return false
    return true
}

var p = {};
trace(p.isEmpty()); // true
var p2 = {a:1}
trace(p2.isEmpty()); // false

ObjectUtil.getClassInfo(obj).properties.length > 0

若对象包含一些“文本”,但as3无法将其识别为String,请将其转换为String并检查它是否为空。

var checkObject:String = myObject;

if(checkObject == '')
{
  trace('object is empty');
}

这取决于你的对象是什么,或者更确切地说,取决于你对它的期望。例如,如果你的对象应该包含你正在寻找的名为name的属性,你可以这样做

if(objSomeItem == null || objSomeItem.name == null || objSomeItem.name.length == 0)
{
 trace("object is empty");
}

var arySomeItems = objSomeItem as Array;
if(objSomeItem == null || arySomeItems == null || arySomeItems.length == 0)
{
  trace("object is empty");
}

您还可以通过反射使用其他方式,例如ObjectUtil.getClassInfo,然后枚举属性以检查设置值。…本课程帮助:

import flash.utils.describeType;
import flash.utils.getDefinitionByName;

public class ReflectionUtils 
{
    /** Returns an Array of All Properties of the supplied object */
    public static function GetVariableNames(objItem:Object):Array
    {
        var xmlPropsList:XMLList = describeType(objItem)..variable;
        var aryVariables:Array = new Array();
        if (xmlPropsList != null)
        {
            for (var i:int; i < xmlPropsList.length(); i++)
            {
                aryVariables.push(xmlPropsList[i].@name);
            }
        }

        return aryVariables;
    }

    /** Returns the Strongly Typed class of the specified library item */
    public static function GetClassByName($sLinkageName:String):Class
    {
        var tObject:Class = getDefinitionByName($sLinkageName) as Class;
        return tObject;
    }

    /** Constructs an instance of the speicified library item */
    public static function ConstructClassByName($sLinkageName:String):Object
    {
        var tObject:Class = GetClassByName($sLinkageName);
        //trace("Found Class: " + tMCDefinition);
        var objItem:* = new tObject();
        return objItem;
    }

    public static function DumpObject(sItemName:String, objItem:Object):void
    {
        trace("*********** Object Dump: " + sItemName + " ***************");
        for (var sKey:String in objItem)
        {
            trace("    " + sKey +": " + objItem[sKey]);
        }
    }
    //}
}

另一件需要注意的事情是,您可以使用一个简单的for循环来检查对象的属性,这就是这个dumppobject函数的作用。

您可以直接按如下方式进行检查,

var obj:Object = new Object();
if(obj == null)
{
//Do something
}

function isEmptyObject(obj){
    return JSON.stringify(obj) === '{}';
}

var i:int = myObject.hasProperty("length") ? myObject.length: 0;