检查值是否是一个数字 [英] Check if value is a number

问题描述

如何简单地检查 int 或 uint 类型的返回值是否是一个数字？

解决方案

简单：

  if（_myValue是Number）
 {
 fire（）; 
 $ b $ //结束如果
  

请记住，如果 _myValue 是 int



$ c>或 uint ，则（_ myValue是Number）也等于 true 。如果您想知道 _myValue 是不是一个整数（int）或无符号整数（uint）的数字，换句话说就是一个浮点数，那么您可以简单地修改条件如下：



 （_ myValue是数字&&！（_ myValue是int）&&！（_ myValue ）
  

让我们来看一个例子：



 包
 {
 import flash.display.Sprite; 
 import flash.events.Event; 
 $ b $ public class Main extends Sprite 
 {
 
 public function Main（）：void 
 {
 if（stage）init 
 else addEventListener（Event.ADDED_TO_STAGE，init）; 
 
 
 private function init（e：Event = null）：void 
 {
 removeEventListener（Event.ADDED_TO_STAGE，init）; 
 
 var number1：Object = 1; // int 
 var number2：Object = 1.1; // float 
 var number3：Object = 0x000000; // uint 
 
 trace（number1 is Number）; // true 
 trace（number2 is Number）; // true 
 trace（number3 is Number）; // true 
 
 trace（number1 is Number&&！（number1 is int）&&！（number1 is uint））; （number2是Number&&！（number2是int）&&！（number2 is uint））; //假
 trace // true 
 trace（number3 is Number&&！（number3 is int）&！（number3 is uint））; // 
 
} 
 
} 
 
} 
  




How can i simply check if a returned value of type int or uint is a number?

解决方案

Simple:

if(_myValue is Number)
{
    fire();

}// end if

[UPDATE]

Keep in mind that if _myValue is of type int or uint, then (_myValue is Number) will also equate to true. If you want to know if _myValue is a number that isn't an integer(int) or unsigned integer (uint), in other words a float, then you can simply modify the conditional as follows:

(_myValue is Number && !(_myValue is int) && !(_myValue is uint))

Let's look at an example:

package 
{
    import flash.display.Sprite;
    import flash.events.Event;

    public class Main extends Sprite 
    {

        public function Main():void 
        {
            if (stage) init();
            else addEventListener(Event.ADDED_TO_STAGE, init);
        }

        private function init(e:Event = null):void 
        {
            removeEventListener(Event.ADDED_TO_STAGE, init);

            var number1:Object = 1; // int
            var number2:Object = 1.1; // float
            var number3:Object = 0x000000; // uint

            trace(number1 is Number); // true
            trace(number2 is Number); // true
            trace(number3 is Number); // true

            trace(number1 is Number && !(number1 is int) && !(number1 is uint)); // false
            trace(number2 is Number && !(number2 is int) && !(number2 is uint)); // true
            trace(number3 is Number && !(number3 is int) && !(number3 is uint)); // false

        }

    }

}

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