PHP常用技巧总结（附函数代码）

php文件读取函式

//文件读取函式
function php_read($file_name) {
$fd=fopen($file_name,r);
while($bufline=fgets($fd, 4096)){
$buf.=$bufline;
}
fclose($fd);
return $buf;
}
?>

文件写入函式

//文件写入函式
function php_write($file_name,$data,$method=”w”) {
$filenum=@fopen($file_name,$method);
flock($filenum,lock_ex);
$file_data=fwrite($filenum,$data);
fclose($filenum);
return $file_data;
}
?>

静态页面生成函式

//静态页面生成函式
function phptohtm($filefrom,$fileto,$u2u=1){
if($u2u==1){
$data=php_read($filefrom);
}else{
$data=$filefrom;
}
php_write($fileto,$data);
return true;
}
?>

指定条件信息数量检索函式

//指定条件信息数量检索函式
function rec_exist($table,$where){
$query=”select count(*) as num from $table “.$where;
$result=mysql_query($query) or die(nerror(1));
$rowcount=mysql_fetch_array($result);
$num=$rowcount["num"];
if ($num==0){
return false;
}
return $num;
}
?>

目录删除函式

//目录删除函式
function del_dir($directory){
$mydir=dir($directory);
while($file=$mydir->read()){
if((is_dir(“$directory/$file”)) and ($file!=”.”) and ($file!=”..”)){
del_dir(“$directory/$file”);
}else{
if(($file!=”.”) and ($file!=”..”)){
unlink(“$directory/$file”);
//echo “unlink $directory/$file ok “;
}
}
}
$mydir->close();
rmdir($directory);
//echo “rmdir $directory ok “;
}
?>

目录名称合法性检测函式

//目录名称合法性检测
function isen($str){
$ret=”";
for($i=0;$i $p=ord(substr($str,$i,1));
if(($p<48 & $p!=45 & $p!=46) || ($p>57 & $p<65) || ($p>90 & $p<97 & $p!=95) || $p>122){
nerror(“不符合规范!”);
}
$ret.=chr($p);
}
return $ret;
}
?>

php分页函数

//分页函数
function splitlist($halt,$lrlist,$echocnt,$paper,$table,$where,$page_id,$userid){
global $splitstr,$sumcnt;
if($paper==”" || $sumcnt==”"){
$query = “select count(*) as num from $table $where”;
$result = mysql_query($query);
$row = mysql_fetch_array($result);
$sumcnt=$row["num"];
if($sumcnt==0){
nerror(“该版内还没有选择发布新闻 !”);
}
$paper=1;
}
$sumpaper=($sumcnt-$sumcnt%$echocnt)/$echocnt;
if(($sumcnt%$echocnt)!=0) $sumpaper+=1;
if($sumpaper==1 && $halt==0) return($where);
$enwhere=base64_encode(base64_encode($where));
if(($lrlist*2+1) < $sumpaper){
if(($paper-$lrlist) < 2){
$tract=1;
$sub=$lrlist*2+1;
}else if(($paper+$lrlist) >= $sumpaper){
$tract=$sumpaper-($lrlist*2);
$sub=$sumpaper;
}else{
$tract=$paper-$lrlist;
$sub=$paper+$lrlist;
}
}else{
$tract=1;
$sub=$sumpaper;
}
$uppaper=$paper-1;
$downpaper=$paper+1;
$startcnt=($paper-1)*$echocnt;
$where.=” limit ${ startcnt },${ echocnt }”;
if($tract > 1) { $splitstr=”【 << “; }
else $splitstr=”【 << “;
for($i=$tract;$i<=$sub;$i++){
if ($i!=$paper) $splitstr.=”".$i.” “;
else $splitstr.=”".$i.” “;
}
if ($sub!=$sumpaper) $splitstr.=”>> 】”;
else $splitstr.=”>> 】”;
return($where);
}
?>

php关于分页函式的使用说明

/*
#### 检索分页函式 ####
int $halt – 检索结果仅分1页时是否(1/0)显示页码条
int $lrlist – (页码条显示页码数-1)/2
int $echocnt – 检索时每页显示记录的数量
int $paper – 页数，预提取：$paper=$http_get_vars[paper];
varchar $table – 数据表名,预附值：$table=”db.table”;
varchar $where – 检索条件，预附值：$where=”where field='value'”;
varchar $enwhere – 将原$where进行两次base64_encode()编码后以get的方式提交
varchar $splitstr – 页码条输出字串，执行函式后在相应的位置执行 echo $splitstr;
函式调用前需获取变量 -
$paper=$http_get_vars[paper];
$sumcnt=$http_get_vars[sumcnt];
$enwhere=$http_get_vars[enwhere];
return (varchar $where) – 分页后检索语句的检索条件
注意：本函式需调用出错处理函式 nerror($error);
*/
php图片文件上传函式
//图片文件上传函式
function upload_img($uploadfile,$uploadfile_name,$uploadfile_size,$uploadpath,$max_size=64){
//$timelimit=60; //设置超时限制时间 缺省时间为 30秒 设置为0时为不限时
//set_time_limit($timelimit);
if(($uploadfile!= “none” )&&($uploadfile != “” )){
$filename=$uploadpath.$uploadfile_name;
if($uploadfile_size <1024){
$filesize=”(string)$uploadfile_size” . “字节”;
}elseif($uploadfile_size <(1024 * $max_size)){
$filesize=number_format((double)($uploadfile_size / 1024), 1) . ” kb”;
}else{
nerror(“文件超过限制大小!”);
}
//{
//$filesize=”number_format((double)($uploadfile_size” / (1024 * 1024)), 1) . ” mb”;
// }
if(!file_exists($filename)){
if(copy($uploadfile,$filename)){
return “$uploadfile_name ($filesize)”;
}else{
nerror(“文件 $uploadfile_name 上载失败!”);
}
unlink($uploadfile);
}else{
nerror(“文件 $uploadfile_name 已经存在!”);
}
//set_time_limit(30); //恢复缺省超时设置
}
}

以下是一些小技巧：

php如何判断ip地址合法性
if(!strcmp(long2ip(sprintf(“%u”,ip2long($ip))),$ip)) echo “is ipn”;
—-
email的正则判断
eregi(“^[_.0-9a-za-z-]+@([0-9a-za-z][0-9a-za-z_-]+.)+[a-za-z]$”, $email);
检测ip地址和mask是否合法的例子

$ip = '192.168.0.84′;
$mask = '255.255.255.0′;
$network = '192.168.0′;
$ip = ip2long($ip);
$mask = ip2long($mask);
$network = ip2long($network);
if( ($ip & $mask) == $network) echo “valid ip and maskn”;
?>
—-
php文件下载头部输出如何设定
header(“content-type: application/x-download”);
header(“content-disposition: attachment; filename=$file_download_name;”);
header(“accept-ranges: bytes”);
header(“content-length: $download_size”);
echo ‘xxx'
php用header输出ftp下载方式,并且支持断点续传
一个例子:
header(‘pragma: public');
header(‘cache-control: private');
header(‘cache-control: no-cache, must-revalidate');
header(‘accept-ranges: bytes');
header(‘connection: close');
header(“content-type: audio/mpeg”);
header(“location:ftp://download:1bk3l4s3k9s2@232.2.22.22/2222/web技术开发知识库/cn_web.rmvb”);
php正则匹配中文
ereg(“^[".chr(0xa1)."-".chr(0xff)."]+$”, $str);
批量替换文本里面的超级链接
function urlparse($str = ”){
if (” == $str) return $str;
$types = array(“http”, “ftp”, “https”);
$replace = <<
”.htmlentities('1′).htmlentities('2′).”
eophp;
$ret = $str;
while(list(,$type) = each($types)){
$ret = preg_replace(“|($type://)([^s]*)|ie “, $replace, $ret);
}
return $ret;
}