最近刚刚完成手中的项目，比较闲。来这儿转转，把积累的一些技巧分享给大家！
1、关于PHP重定向
方法一：header("Location: index.php");
方法二：echo "<script>window.location =\"$PHP_SELF\";</script>";
方法三：echo "<META HTTP-EQUIV=\"Refresh\" CONTENT=\"0; URL=index.php\">";

2、获取访问者浏览器

function browse_infor()
{
$browser="";$browserver="";
$Browsers =array("Lynx","MOSAIC","AOL","Opera","JAVA","MacWeb","WebExplorer","OmniWeb");
$Agent = $GLOBALS["HTTP_USER_AGENT"];
for ($i=0; $i<=7; $i++)
{
if (strpos($Agent,$Browsers[$i]))
{
$browser = $Browsers[$i];
$browserver ="";
}
}
if (ereg("Mozilla",$Agent) && !ereg("MSIE",$Agent))
{
$temp =explode("(", $Agent); $Part=$temp[0];
$temp =explode("/", $Part); $browserver=$temp[1];
$temp =explode(" ",$browserver); $browserver=$temp[0];
$browserver =preg_replace("/([\d\.]+)/","\1",$browserver);
$browserver = " $browserver";
$browser = "Netscape Navigator";
}
if (ereg("Mozilla",$Agent) && ereg("Opera",$Agent))
{
$temp =explode("(", $Agent); $Part=$temp[1];
$temp =explode(")", $Part); $browserver=$temp[1];
$temp =explode(" ",$browserver);$browserver=$temp[2];
$browserver =preg_replace("/([\d\.]+)/","\1",$browserver);
$browserver = " $browserver";
$browser = "Opera";
}
if (ereg("Mozilla",$Agent) && ereg("MSIE",$Agent))
{
$temp = explode("(", $Agent); $Part=$temp[1];
$temp = explode(";",$Part); $Part=$temp[1];
$temp = explode(" ",$Part);$browserver=$temp[2];
$browserver =preg_replace("/([\d\.]+)/","\1",$browserver);
$browserver = " $browserver";
$browser = "Internet Explorer";
}
if ($browser!="")
{
$browseinfo = "$browser$browserver";
}
else
{
$browseinfo = "Unknown";
}
return $browseinfo;
}
//调用方法$browser=browseinfo() ;直接返回结果

3、获取访问者操作系统
function osinfo() {
$os="";
$Agent = $GLOBALS["HTTP_USER_AGENT"];
if (eregi(win,$Agent) && strpos($Agent, 95)) {
$os="Windows 95";
}
elseif (eregi(win 9x,$Agent) && strpos($Agent, 4.90)) {
$os="Windows ME";
}
elseif (eregi(win,$Agent) && ereg(98,$Agent)) {
$os="Windows 98";
}
elseif (eregi(win,$Agent) && eregi(nt 5\.0,$Agent)) {
$os="Windows 2000";
}
elseif (eregi(win,$Agent) && eregi(nt,$Agent)) {
$os="Windows NT";
}
elseif (eregi(win,$Agent) && eregi(nt 5\.1,$Agent)) {
$os="Windows XP";
}
elseif (eregi(win,$Agent) && ereg(32,$Agent)) {
$os="Windows 32";
}
elseif (eregi(linux,$Agent)) {
$os="Linux";
}
elseif (eregi(unix,$Agent)) {
$os="Unix";
}
elseif (eregi(sun,$Agent) && eregi(os,$Agent)) {
$os="SunOS";
}
elseif (eregi(ibm,$Agent) && eregi(os,$Agent)) {
$os="IBM OS/2";
}
elseif (eregi(Mac,$Agent) && eregi(PC,$Agent)) {
$os="Macintosh";
}
elseif (eregi(PowerPC,$Agent)) {
$os="PowerPC";
}
elseif (eregi(AIX,$Agent)) {
$os="AIX";
}
elseif (eregi(HPUX,$Agent)) {
$os="HPUX";
}
elseif (eregi(NetBSD,$Agent)) {
$os="NetBSD";
}
elseif (eregi(BSD,$Agent)) {
$os="BSD";
}
elseif (ereg(OSF1,$Agent)) {
$os="OSF1";
}
elseif (ereg(IRIX,$Agent)) {
$os="IRIX";
}
elseif (eregi(FreeBSD,$Agent)) {
$os="FreeBSD";
}
if ($os==) $os = "Unknown";
return $os;
}
//调用方法$os=os_infor() ;

4、文件格式类
$mime_types = array(
gif => image/gif,
jpg => image/jpeg,
jpeg => image/jpeg,
jpe => image/jpeg,
bmp => image/bmp,
png => image/png,
tif => image/tiff,
tiff => image/tiff,
pict => image/x-pict,
pic => image/x-pict,
pct => image/x-pict,
tif => image/tiff,
tiff => image/tiff,
psd => image/x-photoshop,

swf => application/x-shockwave-flash,
js => application/x-javascript,
pdf => application/pdf,
ps => application/postscript,
eps => application/postscript,
ai => application/postscript,
wmf => application/x-msmetafile,

css => text/css,
htm => text/html,
html => text/html,
txt => text/plain,
xml => text/xml,
wml => text/wml,
wbmp => image/vnd.wap.wbmp,

mid => audio/midi,
wav => audio/wav,
mp3 => audio/mpeg,
mp2 => audio/mpeg,

avi => video/x-msvideo,
mpeg => video/mpeg,
mpg => video/mpeg,
qt => video/quicktime,
mov => video/quicktime,

lha => application/x-lha,
lzh => application/x-lha,
z => application/x-compress,
gtar => application/x-gtar,
gz => application/x-gzip,
gzip => application/x-gzip,
tgz => application/x-gzip,
tar => application/x-tar,
bz2 => application/bzip2,
zip => application/zip,
arj => application/x-arj,
rar => application/x-rar-compressed,

hqx => application/mac-binhex40,
sit => application/x-stuffit,
bin => application/x-macbinary,

uu => text/x-uuencode,
uue => text/x-uuencode,

latex=> application/x-latex,
ltx => application/x-latex,
tcl => application/x-tcl,

pgp => application/pgp,
asc => application/pgp,
exe => application/x-msdownload,
doc => application/msword,
rtf => application/rtf,
xls => application/vnd.ms-excel,
ppt => application/vnd.ms-powerpoint,
mdb => application/x-msaccess,
wri => application/x-mswrite,
);

5、php生成excel文档
<?
header("Content-type:application/vnd.ms-excel");
header("Content-Disposition:filename=test.xls");
echo "test1\t";
echo "test2\t\n";
echo "test1\t";
echo "test2\t\n";
echo "test1\t";
echo "test2\t\n";
echo "test1\t";
echo "test2\t\n";
echo "test1\t";
echo "test2\t\n";
echo "test1\t";
echo "test2\t\n";
?>
//改动相应文件头就可以输出.doc .xls等文件格式了

6、时间比较问题
举一个简单例子说明:比如一个论坛对当天发表的贴子用new图片标记一下。
方法一：
//$db->rows[$i][date]中为数据库中datetime字段值.
$today=time();
$theDay=date("Y-m-d H:i:s",$today-24*3600);
$newTag=$db->rows[$i][date]>=$theDay?"<img src=../image/newinfor.gif>":"";
方法二：
$newTag=$db->rows[$i][date]>=date("Y-m-d 00:00:00")?"<img src=../image/newinfor.gif>":"";
7、PHP中对数据库操作的封装