javascript

CHAPTER 6 ■ FUNCTIONS AND ARRAYS
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"16": [1994, 53, 61],
"17": [1993, 75, 87],
"length": 18,
"callee": argumentsToArray
};
Inserting or Deleting Elements from an Array
Now then, say the elements for the 2000–2002 seasons are invalid inasmuch as the wins and losses are
reversed, and 2002 is in there twice. To delete those four invalid elements and insert new ones in their
place, we can invoke splice() on pirates.
• The first parameter is the index of the first element to delete, so 8 for the 2002
season.
• The second parameter is the number of elements to delete, which would be 4.
• From there, any additional parameters are elements to splice into the array. Note
that it’s OK to add more or fewer elements than you deleted; JavaScript will keep
the array indexes sequential behind the scenes.
So if we add three elements in place of the four invalid ones, the indexes in pirates remain
sequential, ordered 0 to 17 as Figure 6–39 displays.
var pirates = [[2010, 57, 105],
[2009, 62, 99],
[2008, 67, 95],
[2007, 68, 94],
[2006, 67, 95],
[2005, 67, 95],
[2004, 72, 89],
[2003, 75, 87],
[2002, 89, 72],
[2002, 89, 72],
[2001, 100, 62],
[2000, 93, 69],
[1999, 78, 83],
[1998, 69, 93],
[1997, 79, 83],
[1996, 73, 89],
[1995, 58, 86],
[1994, 53, 61],
[1993, 75, 87]];
pirates.splice(8, 4, [2002, 72, 89], [2001, 62, 100], [2000, 69, 93]);
console.dir(pirates);