Flash / Flex / ActionScript/String/indexOf lastIndexOf

Find all the occurrences of a substring.

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var sTitle:String = new String("ActionScript Bible");
       var nMatch:Number = sTitle.indexOf("i");
       while(nMatch != -1) {
         trace(nMatch);
         nMatch = sTitle.indexOf("i", nMatch + 1);
       }
        

   }
 }

} 3 9 14

       </source>
   
  

Finding Substrings

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var sTitle:String = new String("ActionScript");
       trace(sTitle.indexOf("ActionScript")); 
       trace(sTitle.indexOf("i"));  
       trace(sTitle.lastIndexOf("i"));  
       trace(sTitle.indexOf("i", 4));  
       trace(sTitle.lastIndexOf("i", 12));  
       trace(sTitle.indexOf("q"));  
       trace(sTitle.lastIndexOf("g"));  
       
   }
 }

} 0 3 9 9 9 -1 -1

       </source>
   
  

Is indexOf case sensitive

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var example:String = "Cool. This is a cool as both cool (lowercase) and Cool.";
       
       var search:String = "cool";
       
       trace( example.indexOf( search ) );

   }
 }

}

       </source>
   
  

Returns everything before the last period, if any.

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       trace( removeExtension( "document.jpg" ) );       // Displays: document
       trace( removeExtension( "document" ) );           // Displays: document
       trace( removeExtension( "document.1.jpg" ) );     // Displays: document.1
       trace( extractExtension( "document.jpg" ) );      // Displays: .jpg
       trace( extractExtension( "document" ) );          // Displays nothing
       trace( extractExtension( "document.1.jpg" ) );    // Displays: .jpg

   }
   private function removeExtension( filename:String ):String {
     var extensionIndex:Number = filename.lastIndexOf( "." );
     if ( extensionIndex == -1 ) {
       return filename;
     } else {
       return filename.substr( 0, extensionIndex );
     } 
   }
   
   private function extractExtension( filename:String ):String {
     var extensionIndex:Number = filename.lastIndexOf( "." );
     if ( extensionIndex == -1 ) {
       return "";
     } else {
       return filename.substr( extensionIndex + 1, filename.length );
     } 
   }
 }

}

       </source>
   
  

Searching for a Substring

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var example:String = "This string contains the word cool twice. Very cool.";
       var index:int = example.indexOf( "cool" );
       if ( index != -1 ) {
         trace( "String contains word cool at index " + index );
       }
   }
 }

}

       </source>
   
  

Use indexOf and lastIndexOf to locate specific string

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var sEmail:String = new String("info@your.ru");
        
       var nCheckOne:Number = sEmail.indexOf("@");
       var nCheckTwo:Number = sEmail.lastIndexOf(".");
       if (nCheckOne!= -1 && nCheckTwo!= -1 && nCheckOne < nCheckTwo){
           trace("good email address");
       }
   }
 }

}

       </source>
   
  

Use indexOf( ) in a while statement to get the indices of every occurrence of a substring

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var example:String = "This string contains the word cool. Very cool. Yes, cool.";
       var index:int =  -1;
       while ( ( index = example.indexOf( "cool", index + 1 ) ) != -1 ) {
       
         trace( "String contains word cool at index " + index );
       }
   }
 }

}

       </source>
   
  

Use indexOf in while loop to count the instance of a substring

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){

       var story:String = "It was a dark and stormy night...";
       var pattern:String = "a";
       var count:int = 0;
       var startIndex:int = 0;
       while (story.indexOf(pattern, startIndex) != -1) {
          count++;
          startIndex = story.indexOf(pattern, startIndex) + 1;
       }
       trace(count);
   }
 }

}

       </source>
   
  

Use indexOf to check the existance of an substring

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var sTitle:String = new String("ActionScript Demo");
       var nIndex:Number = sTitle.indexOf("Script");
       if(nIndex != -1) {
         trace("substring was found");
       }
   }
 }

}

       </source>
   
  

Use lastIndexOf to search string

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var example:String = "This string contains the word cool twice. Very cool.";
       
       var index:int =  example.lastIndexOf( "cool" );
       
       if ( index != -1 ) {
         trace( "String contains word cool at index " + index );
       }
       index = example.lastIndexOf( "cool", index - 1 );
       
       if ( index != -1 ) {
         trace( "String contains word cool at index " + index );
       }
   }
 }

}

       </source>
   
  

Use offset index in indexOf method to search substring

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var example:String = "This string contains the word cool twice. Very cool.";
       var index:int = example.indexOf( "cool" );
       
       if ( index != -1 ) {
         trace( "String contains word cool at index " + index );
       }
       
       index = example.indexOf( "cool", index + 1 );
       
       if ( index != -1 ) {
         trace( "String contains word cool at index " + index );
       }
   }
 }

}

       </source>
   
  

Use offset in lastIndexOf method

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var example:String = "This string contains the word cool. Very cool. Yes, cool.";
       
       var index:int =  example.length;
       
       while ( ( index = example.lastIndexOf( "cool", index - 1 ) ) != -1 ) {
         trace( "String contains word cool at index " + index );
       }
   }
 }

}

       </source>
   
  

Use the lastIndexOf method to get the file extension name

   <source lang="java">

package{

 import flash.display.Sprite;
 
 public class Main extends Sprite{
   public function Main(){
       var filename:String = "document.jpg";
       var extensionIndex:Number = filename.lastIndexOf( "." );
       
       var extension:String = filename.substr( extensionIndex + 1, filename.length );
       trace( "The file extension is " + extension );
   }
 }

}

       </source>