length (Array.length プロパティ)

var my_array:Array = new Array();
trace(my_array.length); // initial length is 0
my_array[0] = "a";
trace(my_array.length); // my_array.length is updated to 1
my_array[1] = "b";
trace(my_array.length); // my_array.length is updated to 2
my_array[9] = "c";
trace(my_array.length); // my_array.length is updated to 10
trace(my_array); 
// displays: 
// a,b,undefined,undefined,undefined,undefined,undefined,undefined,undefined,c

// if the length property is now set to 5, the array will be truncated
my_array.length = 5; 
trace(my_array.length); // my_array.length is updated to 5
trace(my_array); // outputs: a,b,undefined,undefined,undefined