[PHP] a set of commonly used practical functions

[PHP] a collection of frequently used practical functions is about to learn php. I found that many functions need to be used and can be written by myself, so I found common php functions, from various major php systems, php practical functions are definitely used.

Function GetIP () {// obtain the IP address
If ($ _ SERVER ["HTTP_X_FORWARDED_FOR"])
$ Ip = $ _ SERVER ["HTTP_X_FORWARDED_FOR"];
Else if ($ _ SERVER ["HTTP_CLIENT_IP"])
$ Ip = $ _ SERVER ["HTTP_CLIENT_IP"];
Else if ($ _ SERVER ["REMOTE_ADDR"])
$ Ip = $ _ SERVER ["REMOTE_ADDR"];
Else if (getenv ("HTTP_X_FORWARDED_FOR "))
$ Ip = getenv ("HTTP_X_FORWARDED_FOR ");
Else if (getenv ("HTTP_CLIENT_IP "))
$ Ip = getenv ("HTTP_CLIENT_IP ");
Else if (getenv ("REMOTE_ADDR "))
$ Ip = getenv ("REMOTE_ADDR ");
Else
$ Ip = "Unknown ";
Return $ ip;
}

Function DateAdd ($ date, $ int, $ unit = "d") {// increase of time (you can also improve it to increase by hour, minute, and second, and then add time)
$ DateArr = explode ("-", $ date );
$ Value [$ unit] = $ int;
Return date ("Y-m-d", mktime (0, 0, 0, $ dateArr [1] + $ value ['M'], $ dateArr [2] + $ value ['D'], $ dateArr [0] + $ value ['Y']);
}

Function GetWeekDay ($ date) {// calculate the day of the week
$ DateArr = explode ("-", $ date );
Return date ("w", mktime (0, 0, 0, $ dateArr [1], $ dateArr [2], $ dateArr [0]);
}

The code is as follows:

Function check_date ($ date) {// check whether the date is valid
$ DateArr = explode ("-", $ date );
If (is_numeric ($ dateArr [0]) & is_numeric ($ dateArr [1]) & is_numeric ($ dateArr [2]) {
Return checkdate ($ dateArr [1], $ dateArr [2], $ dateArr [0]);
}
Return false;
}
Function check_time ($ time) {// check whether the time is valid
$ TimeArr = explode (":", $ time );
If (is_numeric ($ timeArr [0]) & is_numeric ($ timeArr [1]) & is_numeric ($ timeArr [2]) {
If ($ timeArr [0]> = 0 & $ timeArr [0] <= 23) & ($ timeArr [1]> = 0 & $ timeArr [1] <= 59) & ($ timeArr [2]> = 0 & $ timeArr [2] <= 59 ))
Return true;
Else
Return false;
}
Return false;
}

Function DateDiff ($ date1, $ date2, $ unit = "") {// Time comparison function, returns the seconds, minutes, hours, or days of difference between two dates
Switch ($ unit ){
Case's ':
$ Pidend = 1;
Break;
Case 'I ':
$ Pidend = 60;
Break;
Case 'H ':
$ Pidend = 3600;
Break;
Case 'D ':
$ Pidend = 86400;
Break;
Default:
$ Pidend = 86400;
}
$ Time1 = strtotime ($ date1 );
$ Time2 = strtotime ($ date2 );
If ($ time1 & $ time2)
Return (float) ($ time1-$ time2)/$ pidend;
Return false;
}

The code is as follows:

Function get_innerhtml ($ html, $ label) {// gets an html string between html tags.
$ Result_arr = preg_split ("/<\/". $ label. ">/I", $ html );
$ Pattern = "/<". $ label. ". *?> /I ";
For ($ I = 0; $ I <count ($ result_arr); $ I ++ ){
List ($ left, $ right) = preg_split ($ pattern, $ result_arr [$ I], 2 );
$ Result_arr [$ I] = $ right;
}
Return $ result_arr;
}
// Example: echo get_innerhtml ("Something"," Td "); // will print" something ".

Function get_input_value ($ input) {// obtain the Value in the HTML code of the Input.
$ Pos = stripos ($ input, "value =") + 6;
If ($ pos! = False ){
$ Input = substr ($ input, $ pos );
If (substr ($ input, 0, 1) = "\"")
Return substr ($ input, 1, strpos ($ input, "\" ", 1)-1 );
Else
Return substr ($ input, 0, strpos ($ input, "")-1 );
}
Return false;
}

Function getcontentbetween ($ a, $ B, $ str) {// Obtain the string between $ a and $ B in string $ str.
If ($ str! = "" & $! = "" & $ B! = ""){
$ Start = strpos ($ str, $ a) + strlen ($ );
Return substr ($ str, $ start, strpos ($ str, $ B, $ start + 1)-$ start );
}
Return false;
}

1. PHP redirection

The code is as follows:

Method 1: header ("Location: index. php ");
Method 2: echo" Window. location = "$ PHP_SELF "; ";
Method 3: echo" ";

2. obtain the visitor's browser

The code is as follows:

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;
}
// Call method $ browser = browseinfo (); directly return the result

3. obtain the visitor's operating system

The code is as follows:

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 ('netsd', $ Agent )){
$ OS = "NetBSD ";
}
Elseif (eregi ('bsd', $ Agent )){
$ OS = "BSD ";
}
Elseif (ereg ('oss1', $ Agent )){
$ OS = "OSF1 ";
}
Elseif (ereg ('irix ', $ Agent )){
$ OS = "IRIX ";
}
Elseif (eregi ('freebsd ', $ Agent )){
$ OS = "FreeBSD ";
}
If ($ OS = '') $ OS =" Unknown ";
Return $ OS;
}
// Call method $ OS = OS _infor ();

4. file format
Copy the content to the clipboard code:
$ 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-Forwarded Cr limit pt ',
'PDF '=> 'application/pdf ',
'Ps' => 'application/postscr reject pt ',
'Eps '=> 'application/postscr reject pt ',
'AI' => 'application/postscr reject pt ',
'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 ',

'Av' => '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-uencode ',
'Uuue' => 'text/x-uencode ',

'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. generate an excel file in php

The code is as follows:

Header ("Content-type: application/vnd. ms-excel ");
Header ("Content-Disposition: filename=test.xls ");
Echo "test1t ";
Echo "test2tn ";
Echo "test1t ";
Echo "test2tn ";
Echo "test1t ";
Echo "test2tn ";
Echo "test1t ";
Echo "test2tn ";
Echo "test1t ";
Echo "test2tn ";
Echo "test1t ";
Echo "test2tn ";
?>
// You can change the corresponding file header to export file formats such as .doc. xls.

6. time comparison problems
For example, a forum marks a post posted on the day with a new image.
Method 1:

The code is as follows:

// $ Db-> rows [$ I] [date] indicates the datetime field value in the database.
$ Today = time ();
$ TheDay = date ("Y-m-d H: I: s", $ today-24*3600 );
$ NewTag = $ db-> rows [$ I] [date]> = $ theDay? "":"";

Method 2:

The code is as follows:

$ NewTag = $ db-> rows [$ I] [date]> = date ("Y-m-d 00:00:00 ")? "":"";
// Extract the variables submitted by the page and browser, which is equivalent to enabling PHP. INI to enable global variables.
Copy the content to the clipboard code:
@ Extract ($ _ SERVER, EXTR_SKIP );
@ Extract ($ _ SESSION, EXTR_SKIP );
@ Extract ($ _ POST, EXTR_SKIP );
@ Extract ($ _ FILES, EXTR_SKIP );
@ Extract ($ _ GET, EXTR_SKIP );
@ Extract ($ _ ENV, EXTR_SKIP );
// Obtain the IP address
$ Ip = $ _ SERVER ['remote _ ADDR '];
$ Ip1 = getenv ('http _ X_FORWARDED_FOR ');
If ($ ip1! = "") & ($ Ip1! = "Unknown") $ ip = $ ip1;
// Read the file function

Function readfromfile ($ file_name ){
If (file_exists ($ file_name )){
$ Filenum = fopen ($ file_name, "r ");
Flock ($ filenum, LOCK_EX );
$ File_data = fread ($ filenum, filesize ($ file_name ));
Rewind ($ filenum );
Fclose ($ filenum );
Return $ file_data;
}
}
// File writing function
Copy the content to the clipboard code:

The code is as follows:

Function writetofile ($ file_name, $ data, $ method = "w "){
$ Filenum = fopen ($ file_name, $ method );
Flock ($ filenum, LOCK_EX );
$ File_data = fwrite ($ filenum, $ data );
Fclose ($ filenum );
Return $ file_data;
}
// Quick page redirection
Copy the content to the clipboard code:
Function turntopage ($ url = "index. php", $ info = "page redirection...", $ second = 2 ){
Print"NNPage turning ....N ";
Print" N ";
Print"N ";
Print"NN ";
Print"

N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print"

N "; Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print" N ";Print"N ";Print" Page redirection prompt information $ Info N "; Print "if your browser does not support automatic jump, click here

N ";
Print"N";
Exit;