Flash / Flex / ActionScript/Language/Comparison Operators

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Checking Equality or Comparing Values

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       trace(5 == 6);    // Displays: false
       trace(6 == 6);    // Displays: true
   }
 }

}

       </source>
   
  


Comparison Operators in Actionscript

   <source lang="java">

Operator Name == Equals != Not equals > Greater than < Less than >= Greater than or equal <= Less than or equal

       </source>
   
  


Equality (==)

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var weather:String = "rain";
       
       if (weather == "rain") {
          trace("bringUmbrella");
       }
   }
 }

}

       </source>
   
  


Greater Than (>) and Less Than (

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var x:int = 0;
       
       var a:int = -1;
       var b:int = 0;
       var c:int = 1;
       
       trace(x <= a); // Displays: false
       trace(x >= a); // Displays: true
       trace(x <= b); // Displays: true
       trace(x >= b); // Displays: true
       trace(x <= c); // Displays: true
       trace(x >= c); // Displays: false
   }
 }

}

       </source>
   
  


Not Equal To (!=)

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var weather:String = "rain";
       
       
       if (weather != "sun") { trace("bringUmbrella"); }
       if (!(weather == "sun")) { trace("bringUmbrella"); }
       
   }
 }

}

       </source>
   
  


Number Comparison

   <source lang="java">


Expression Result 6 == 6 true 6 != 6 false 6 > 6 false 6 < 6 false 6 >= 6 true 6 <= 6 true

       </source>
   
  


Strict equality

   <source lang="java">

!== Strict inequality

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var myVariable:Number = 999;
       if (myVariable == 4){
       trace("if condition true");
       }
       trace(myVariable);
   }
 }

}

       </source>
   
  


The logical inequality operator (!=) returns false if two values are equal and true if they aren"t.

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       trace(5 != 6);    // Displays: true
       trace(6 != 6);    // Displays: false
   }
 }

}

       </source>
   
  


Two composite items are equal only if they both refer to the identical object

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var arrayOne:Array = new Array("a", "b", "c");
       
       var arrayTwo:Array = arrayOne;
       trace(arrayOne == arrayTwo);          // Displays: true
   }
 }

}

       </source>
   
  


Use the <= and >= operators to check if one value is less than or equal to, or greater than or equal to, another value:

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       trace(5 <= 6);   // Displays: true
       trace(5 >= 5);   // Displays: true
   }
 }

}

       </source>
   
  


Use the < and > operators to check if one value is less than or greater than another value:

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       trace(5 < 6);    // Displays: true
       trace(5 > 5);    // Displays: false
   }
 }

}

       </source>
   
  


When comparing primitive datatypes, ActionScript compares them by value.

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var quantity:Number = 6;
       var total:Number = 6;
       trace (quantity == total);         // Displays: true
   }
 }

}

       </source>
   
  


When you compare composite datatypes, ActionScript compares them by reference.

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var arrayOne:Array = new Array("a", "b", "c");
       var arrayTwo:Array = new Array("a", "b", "c");
       trace(arrayOne == arrayTwo);          // Displays: false
   }
 }

}

       </source>