一些使用频率比较高的PHP函数

网络整理 - 08-09

在php开发中，我们经常会遇到一些函数，下面是整理好的，可以直接使用，方便开发效率，不过建议大家一定要先看懂，然后在这个基础上增加功能就提高了自身能力了

1.产生随机字符串函数

function random($length) {

$hash = @#@#;

$chars = @#abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz@#;

$max = strlen($chars) - 1;

mt_srand((double)microtime() * 1000000);

for($i = 0; $i < $length; $i++) {

$hash .= $chars[mt_rand(0, $max)];

}

return $hash;

}

2.截取一定长度的字符串

注：该函数对gb2312使用有效

function wordscut($string, $length ,$sss=0) {

if(strlen($string) > $length) {

if($sss){

$length=$length - 3;

$addstr=@# ...@#;

}

for($i = 0; $i < $length; $i++) {

if(ord($string[$i]) > 127) {

$wordscut .= $string[$i].$string[$i + 1];

$i++;

} else {

$wordscut .= $string[$i];

}

return $wordscut.$addstr;

}

return $string;

}

3.取得客户端ip地址

function getip(){

if (getenv("http_client_ip") && strcasecmp(getenv("http_client_ip"), "unknown"))

$ip = getenv("http_client_ip");

else if (getenv("http_x_forwarded_for") && strcasecmp(getenv("http_x_forwarded_for"), "unknown"))

$ip = getenv("http_x_forwarded_for");

else if (getenv("remote_addr") && strcasecmp(getenv("remote_addr"), "unknown"))

$ip = getenv("remote_addr");

else if (isset($_server[@#remote_addr@#]) && $_server[@#remote_addr@#] && strcasecmp($_server[@#remote_addr@#], "unknown"))
$ip = $_server[@#remote_addr@#];

else

$ip = "unknown";

return($ip);

}
4.创建相应的文件夹

function createdir($dir=@#@#)

{

if (!is_dir($dir))

{

$temp = explode(@#/@#,$dir);

$cur_dir = @#@#;

for($i=0;$i<count($temp);$i++)

{

$cur_dir .= $temp[$i].@#/@#;

if (!is_dir($cur_dir))

{

@mkdir($cur_dir,0777);

}

5.判断邮箱地址

function checkemail($inaddress)

{

return (ereg("^([a-za-z0-9_-])+@([a-za-z0-9_-])+(\.[a-za-z0-9_-])+",$inaddress));
}

6.跳转

function gotourl($message=@#@#,$url=@#@#,$title=@#@#)
{

$html ="<html><head>";

if(!empty($url))

$html .="<metahttp-equiv=@#refresh@# content=\"3;url=@#".$url."@#\">";

$html .="<linkhref=@#../templates/style.css@# type=text/css rel=stylesheet>";

$html .="</head><body> ";

$html .="<tablecellspacing=@#0@#cellpadding=@#0@#border=@#1@#width=@#450@#align=@#center@#>";

$html .="<tr><tdbgcolor=@##ffffff@#>";

$html .="<tableborder=@#1@#cellspacing=@#1@#cellpadding=@#4@#width=@#100%@#>";

$html .="<trclass=@#m_title@#>";

$html .="<td>".$title."</td></tr>";

$html .="<trclass=@#line_1@#><tdalign=@#center@#height=@#60@#>";

$html .=" ".$message." ";

if (!empty($url))

$html .="系统将在3秒后返回 如果您的浏览器不能自动返回,请点击[<a href=".$url." target=_self>这里</a>]进入";
else

$html .="[<a href=@##@#=@#history.go(-1)@#>返回</a>]";

$html .="</td></tr></table></td></tr></table>";

$html .="</body></html>";

echo $html;

exit;

}

7.分页（两个函数配合使用）

function getpage($sql,$page_size=20)

{
global $page,$totalpage,$sums; //out param

$page = $_get["page"];

//$eachpage = $page_size;

$pagesql = strstr($sql," from ");

$pagesql = "select count(*) as ids ".$pagesql;

$result = mysql_query($pagesql);

if($rs = mysql_fetch_array($result)) $sums = $rs[0];

$totalpage = ceil($sums/$page_size);

if((!$page)||($page<1)) $page=1;

$startpos = ($page-1)*$page_size;

$sql .=" limit $startpos,$page_size ";

return $sql;

}

function showbar($string="")

{
global $page,$totalpage;

$out="共".$totalpage."页 ";

$linknum =4;
$start = ($page-round($linknum/2))>0 ? ($page-round($linknum/2)) : "1";

$end = ($page+round($linknum/2))<$totalpage ? ($page+round($linknum/2)) : $totalpage;

$prestart=$start-1;

$nextend=$end+1;

if($page<>1)

$out .= "<ahref=@#?page=1&&".$string."@#title=第一页>第一页</a> ";

if($start>1)

$out.="<ahref=@#?page=".$prestart."@# title=上一页>..<<</a> ";

for($t=$start;$t<=$end;$t++)
{

$out .= ($page==$t) ? "[".$t."] " : "<a$thref=@#?page=$t&&".$string."@#>$t</a> ";
}

if($end<$totalpage)

$out.="<ahref=@#?page=".$nextend."&&".$string."@# title=下一页>>>..</a>";

if($page<>$totalpage)

$out .= " <ahref=@#?page=".$totalpage."&&".$string."@# title=最后页>最后页</a>";

return $out;

}

8.获取新插入数据的id

mysql_insert_id();