Sample code sharing for implementing some small things in PHP

$q = "SELECT CONVERT(TEXT, userinfo.inv) as te FROM userinfo where  (1=1)";

$shijianchuo = strtotime("$logintime");
$past_logintime = date("Y/m/d",$shijianchuo-24*60*60);
$today_time=date("Y-m-d");
$zh_time = strtotime("$today_time");
$yesterday_time= date("Y-m-d ",strtotime("-1 day","$zh_time")) ;
$tomorrow_time= date("Y-m-d ",strtotime("+1 day","$zh_time")) ;

<script language="javascript">
    function check(form){
        if(form.txt_user.value==""){
            alert("请输入用户名");form.txt_user.focus();return false;       
        }
        if(form.txt_pwd.value==""){
            alert("请输入密码");form.txt_pwd.focus();return false;
        }
    }
</script>

$filecount=0;
$dircount=0;
function copydir($dirFrom,$dirTO)
{
    global $filecount;
    global $dircount;
 
    if(is_file($dirTO))
    {
        die("目标不是目录，无法创建目录 $dirTO");
    }
 
    if(!file_exists(dirTO))
    {
        mkdir($dirTO);
        $dircount++;
    }
     
    $handle=opendir($dirFrom);
     
    while(($file=readdir($handle))!==false)
    {
        if($file !="." && $file !="..")
        {
            $fileFrom=$dirFrom.DIRECTORY_SEPARATOR.$file;
            $fileTo=$dirTO.DIRECTORY_SEPARATOR.$file;
             
            if(is_dir($fileFrom))
            {
                copydir($fileFrom,$fileTo);
            }else{
                copy($fileFrom,$fileTo);
                $filecount++;
            }          
        }
    }
    closedir($handle);
 
}
 
copydir(mail,mailbak);
echo "共拷贝".$filecount."文件，共拷贝目录".$dircount."个";

<?php
//将获取当前时间的代码放在一个函数里
function runtime(){
      $times = explode(" ",microtime());
      $nowtime = $times[1]+$times[0];
      return $nowtime;
}
 
//假设这里是页面开头
$start_time = runtime();
 
//这里开始是的页面代码
//your code goes here
 
//假设这里是页面顶部
$end_time = runtime();
$cost_time = $end_time - $start_time;
 
//处理输出执行时间
$cost_time = round($cost_time,4);
 
//输出页面的执行时间
echo "页面执行时间为：".$cost_time."秒";
?>

<?php
/**
* 方法:isdate()
* 功能:判断日期格式是否正确
* 参数:$str 日期字符串 $format日期格式
* 返回:布尔值
*/
function isdate($str,$format="Y-m-d"){
$strArr = explode("-",$str);
if(empty($strArr)){
return false;
}
foreach($strArr as $val){
if(strlen($val)<2){
$val="0".$val;
}
$newArr[]=$val;
}
$str =implode("-",$newArr);
    $unixTime=strtotime($str);
    $checkDate= date($format,$unixTime);
    if($checkDate==$str)
        return true;
    else
        return false;
}
//实例
if(isdate("2010-1-1")){
echo "true";
}else{
echo "false";
}

<?php
 
$filecount=0;
$dircount=0;
 
 
$file="mail";
 
function deleteDir($pathName)
{  
    global $filecount;
    global $dircount;
 
    if(file_exists($pathName))
    {
        if($handle=opendir($pathName))
        {
            while(($file=readdir($handle)) !==false)
                {  
                    if($file !="." && $file !="..")
                    {
                        $file=$pathName.DIRECTORY_SEPARATOR.$file;
                        if( is_dir($file))
                        {  
                            deleteDir($file);
                        }else{
                            if(unlink($file))
                            {  
                                $filecount++;
                                echo "文件<b> $file</b>删除成功<br>";
                            }else{
                                echo "文件<b> $file</b>删除失败<br>";
                            }
                        }
                    }
                }
            }
        closedir($handle); 
        if(rmdir($pathName))
        {  
            $dircount++;
            echo "目录<b> $pathName</b>删除成功<br>";
        }else{
            echo "目录<b> $pathName</b>删除失败<br>";
        }
    }
}
deleteDir($file);
echo "共删除".$filecount."文件，共删除目录".$dircount."个";
?>

<input type=text onBlur="if (this.value.length==0) {alert(&#39;不能为空&#39;);this.focus();}">

<js> 自动n秒后跳转到指定页面儿
2011-08-12 16:44:00
<script type="text/javascript">
var time =10; //时间,秒
function Redirect(){
    window.location = "要跳去的url";
}
var i = 0;
function dis(){
    document.all.s.innerHTML = "还剩" + (time - i) + "秒";
    i++;
}
timer=setInterval(&#39;dis()&#39;, 1000); //显示时间
timer=setTimeout(&#39;Redirect()&#39;,time * 1000); //跳转
</script>
 
 
<span id="s"></span>

<?php 
/** 
* 日历 
*/ 
$time = date(&#39;Y-m-d&#39;);
if (function_exists(&#39;date_default_timezone_set&#39;)) { 
 date_default_timezone_set(&#39;PRC&#39;); 
 } 
$date = isset($_GET[&#39;date&#39;]) ? $_GET[&#39;date&#39;] : $time; 
$date = getdate(strtotime($date)); 
$end = getdate(mktime(0, 0, 0, $date[&#39;mon&#39;] + 1, 1, $date[&#39;year&#39;]) - 1); 
$start = getdate(mktime(0, 0, 0, $date[&#39;mon&#39;], 1, $date[&#39;year&#39;])); 
$pre = date(&#39;Y-m-d&#39;, $start[0] - 1); 
$next = date(&#39;Y-m-d&#39;, $end[0] + 86400);
  
$html = &#39;<table width="90%" border="1" cellspacing="0" cellpadding="0"  
align="center" style="line-height:250%; font-family:Verdana; font-size: 12px;">&#39;; 
$html .= &#39;<tr>&#39;; 
$html .= &#39;<td align="center"><a href="&#39; . $PHP_SELF . &#39;?date=&#39; . $pre . &#39;">上个月</a></td>&#39;; 
$html .= &#39;<td colspan="5" align="center">&#39; . $date[&#39;year&#39;] . &#39;-&#39; . $date[&#39;mon&#39;] . &#39;　　　　<a href=?date=&#39;.date(&#39;Y-m-d&#39;).&#39;>今天</a></td>&#39;; 
$html .= &#39;<td align="center"><a href="&#39; . $PHP_SELF . &#39;?date=&#39; . $next . &#39;">下个月</a></td>&#39;; 
$html .= &#39;</tr>&#39;; 
$html .= &#39;<tr>&#39;; 
$html .= &#39;<td>星期日</td>&#39;; 
$html .= &#39;<td>星期一</td>&#39;; 
$html .= &#39;<td>星期二</td>&#39;; 
$html .= &#39;<td>星期三</td>&#39;; 
$html .= &#39;<td>星期四</td>&#39;; 
$html .= &#39;<td>星期五</td>&#39;; 
$html .= &#39;<td>星期六</td>&#39;; 
$html .= &#39;</tr>&#39;; 
$arr_tpl = array(0 => &#39;&#39;, 1 => &#39;&#39;, 2 => &#39;&#39;, 3 => &#39;&#39;, 4 => &#39;&#39;, 5 => &#39;&#39;, 6 => &#39;&#39;); 
$date_arr = array(); 
$j = 0; 
for ($i = 0; $i < $end[&#39;mday&#39;]; $i++) { 
if (!isset($date_arr[$j])) { 
$date_arr[$j] = $arr_tpl; 
} 
$date_arr[$j][($i+$start[&#39;wday&#39;])%7] = $i+1; 
if ($date_arr[$j][6]) { 
$j++; 
} 
} 
foreach ($date_arr as $value) { 
$html .= &#39;<tr>&#39;; 
foreach ($value as $v) { 
 if ($v>9) {
  $vvv=$v;
 }else{
  $vvv="0".$v;
 }
 $datemm=$date[&#39;year&#39;].&#39;-&#39;.$date[&#39;mon&#39;].&#39;-&#39;.$vvv;
  
if ($v) { 
if ($v == $date[&#39;mday&#39;]) { 
 $html .= &#39;<td><b>&#39; . $vvv . &#39;</b><br>&#39;.$datemm.&#39;</td>&#39;; 
} else { 
 $html .= &#39;<td>&#39; . $vvv . &#39;<br>&#39;.$datemm.&#39; </td>&#39;; 
} 
} else { 
$html .= &#39;<td> </td>&#39;; 
} 
} 
$html .= &#39;</tr>&#39;; 
} 
$html .= &#39;</table>&#39;; 
echo $html; 
?>