php 日期 - 获取当月最后一天

<span> 1</span>     <span>/*</span><span>*
</span><span> 2</span> <span>     *    日期-获取当月最后一天
</span><span> 3</span> <span>     *  @return int
</span><span> 4</span>      <span>*/</span>
<span> 5</span>     <span>public</span> <span>function</span><span> get_lastday() {
</span><span> 6</span>         <span>if</span>(<span>$this</span>->month==2<span>) {
</span><span> 7</span>             <span>$lastday</span> = <span>$this</span>->is_leapyear(<span>$this</span>->year) ? 29 : 28<span>;
</span><span> 8</span>         } <span>elseif</span>(<span>$this</span>->month==4 || <span>$this</span>->month==6 || <span>$this</span>->month==9 || <span>$this</span>->month==11<span>) {
</span><span> 9</span>             <span>$lastday</span> = 30<span>;
</span><span>10</span>         } <span>else</span><span> {
</span><span>11</span>             <span>$lastday</span> = 31<span>;
</span><span>12</span> <span>        }
</span><span>13</span>         <span>return</span> <span>$lastday</span><span>;
</span><span>14</span> <span>    }
</span><span>15</span>     
<span>16</span> 
<span>17</span>     
<span>18</span>     <span>/*</span><span>*
</span><span>19</span> <span>     *    日期-是否是闰年
</span><span>20</span> <span>     *  @return int
</span><span>21</span>      <span>*/</span>
<span>22</span>     <span>public</span> <span>function</span> is_leapyear(<span>$year</span><span>) {
</span><span>23</span>         <span>return</span> <span>date</span>('L', <span>$year</span><span>);
</span><span>24</span>     }