MACROMEDIA FLASH 8-LEARNING ACTIONSCRIPT 2.0 IN FLASH, Manual

Page: 461 / 830

About strings and the String class 461
If a string doesn’t contain a value, its length is set to undefined:
var thirdStr:String;
trace(thirdStr.length); // undefined
You can also use character codes to define a string. For more information on character codes
and character encoding, see
“About strings and the String class” on page 450 .
The following example creates a variable named
myStr
and sets the string’s value based on
ASCII values passed to the
String.fromCharCode()
method:
var myStr:String =
String.fromCharCode(104,101,108,108,111,32,119,111,114,108,100,33);
trace(myStr); // hello world!
Each number listed in the
fromCharCode()
method in the previous code represents a single
character. For example, the ASCII value 104 represents a lowercase h , and the ASCII value 32
represents the space character.
You can also use the
String.fromCharCode()
method to convert Unicode values, although
the unicode value must be converted from hexidecimal to decimal values, as shown in the
following ActionScript:
// Unicode 0068 == "h"
var letter:Number = Number(new Number(0x0068).toString(10));
trace(String.fromCharCode(letter)); // h
You can examine the characters in various positions in a string, as in the following example.
To loop over a string:
1. Create a new Flash document.
2. Add the following ActionScript to Frame 1 of the main Timeline:
var myStr:String = "hello world!";
for (var i:Number = 0; i < myStr.length; i++) {
trace(myStr.charAt(i));
}
3.
Select Control > Test Movie to preview your Flash document. You should see each
character traced to the Output panel on a separate line.
WARN
ING
If your string contains a null byte character (\0), the string value will be truncated.