To implement a function that pushes n months down from a specified time

Timing | function Author: bjbs_270
Some time ago to do one months report statistics with the title of the function, combined with others with mktime () function I wrote a but then always error, depressed pole. Spend a little time on the weekend to write a use, I hope it can be useful to some villagers.

PHP Code:--------------------------------------------------------------------------------

?
/*
* Author: Heart lamp
* Function: To implement a function that pushes n months down from a specified time
* Month ($YMD, $len) $ymd time, $len launch for several months
* $ymd = ' 2005-01-01 ';
*/
Function month ($ymd = ', $len = ' 12 ') {
$month = Array ();
$lang = $lang. " <meta http-equiv=\ "content-type\" content=\ "text/html; Charset=gb2312\ ">";
if ($YMD) {//To determine if the time format is correct
if (!ereg ([0-9]{4})-([0-9]{1,2})-([0-9]{1,2}), $ymd)) {
echo "<script>alert (the date format is not in the function argument); History.back () </script>";
Exit
}
}
if ($len) {
if (!ereg ("[0-9]+", $len)) {
echo $lang. " <script>alert (' The length of time in the function contains illegal fields '); History.back () </script>;
Exit
}
}
for ($i =0; $i < $len; $i + +) {
if ($i ==0) {
$mktime = $ymd Strtotime ($YMD): Time ();
}
$month [] = Date ("Y-m", $mktime);//You can design the format you want according to your needs
$day = Date ("T", $mktime);
if ($i ==0)
$reday = Date ("D", $mktime);
Else
$reday = $day;
$t 1 = $mktime;
$mktime =date ("y-m-d", Mktime ("H", $t 1), date ("I", $t 1), date ("s", $t 1), date ("M", $t 1), date ("D", $t 1)-$reday, date ( "Y", $t 1));
$mktime =strtotime ($mktime);
}
return $month;
}
$month = month ();
foreach ($month as $key => $v) {
echo $v. " <br> ";
}
?>
--------------------------------------------------------------------------------

The effect is as follows:
2005-01
2004-12
2004-11
2004-10
2004-09
2004-08
2004-07
2004-06
2004-05
2004-04
2004-03
2004-02