$BeginDate=date('Y-m-01', strtotime(date("Y-m-d"))); 获取当前月份第一天
echo $BeginDate;
echo date('Y-m-d', strtotime("$BeginDate +1 month -1 day")); 加一个月减去一天。
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function getthemonth($date)
{
$firstday = date('Y-m-01', strtotime($date));
$lastday = date('Y-m-d', strtotime("$firstday +1 month -1 day"));
return array($firstday, $lastday);
}