{"id":95,"date":"2008-07-28T11:03:32","date_gmt":"2008-07-28T15:03:32","guid":{"rendered":"http:\/\/jianmingli.com\/wp\/?p=95"},"modified":"2008-07-28T11:10:00","modified_gmt":"2008-07-28T15:10:00","slug":"php-funpamentals","status":"publish","type":"post","link":"https:\/\/jianmingli.com\/wp\/?p=95","title":{"rendered":"PHP Funpamentals"},"content":{"rendered":"

Basic syntax<\/strong><\/p>\n

Comments
\n\/\/ for single line
\n\/* *\/ for multiple line
\n# for shell style comments<\/p>\n

<\/p>\n

Variables
\n-starts with $
\n-may contain
\n strings
\n numbers
\n arrays
\n-is case sensitive<\/p>\n

Variable variables
\n $foo = ‘bar’;
\n $$foo = ‘baz’;<\/p>\n

Variable reference
\n $black = & $white
\n-unset a variable that is aliased
\n unset($white);
\n \/\/$black still = “snow”<\/p>\n

Global variables inside a fxn
\nfunction foo(){
\n global $a;
\n $a += 2;
\n}<\/p>\n

Static variable<\/p>\n

exit and return
\n-exit(“db fail”);
\n-die(“db fail”);
\n-$db = @mysql_connect(“localhost”, $USERNAME,$PASS)
\nor die(“db fail”);<\/p>\n

Constants
\n-define(‘PUBLISHER’, “O’Reily”);<\/p>\n

Strings<\/strong><\/p>\n

String concat
\n‘therer were’ . $n . ‘ ducks.’ ;
\nQuotes
\n ‘some’
\n “some”<\/p>\n

Here document
\n $s = <<< END\n Foo\n END;\n\nPrint strings\n\n echo \"hello\";\n print(\"hello\") \/\/returns bool\n printf()\n '%.2f', 27.452 \/\/27.45\n '%d %x', 214,214 \/\/214 d6\n '%03d',7 \/\/007\n '%02d\/%04y' \/\/15\/2004\n '%.2f%%',2.1\/\/2.10%\n '$%5.2f',4.1 \/\/$% 4.10\n sprintf: save instead print\n print_r()\n var_dump\n\nString manipulation\n\nstrlen() \ntrim()\/ltrim\/rtrim\nstrtolower() strtoupper()\nucfirst() ucwords()\nString fxn fon html\nhtmlspecialchars()\nhtmlentities()\nstrip_tags()\nget_meta_tags()\nraw_url_encode()\nraw_url_decode()\nurl_encode()\nurl_decode()\nFor sql\nadd_slash()\n\nComparison\n$1 == $2\nstrcmp($1,$2); \/\/retuns -1,0,1\nstrcasecmp() \/\/conv to lower case\nstrnatcmp() \/\/natural order\nsoundex($str) \/\/sounds alike\nmetaphone($str)\nsimilar_text($str1,$str2[,pcnt]);\nlevenshtein($str1,$str2[,$cost_ins, $cost_rep,$cost_del]);\n\nManipulate string\nsubstr(string,start[, lengh]);\nsubstr_count(big_str, small_str);\nsubstr_replace(ori, new, start[, len]);\nstrrev($str); \/\/reverse string\nstr_repeat($str, count);\nstr_pad(topad,len[,with[,padtype]]};\n\nDecomp string\n$array=explode(sep,str[,limit]};\nimplode(sep,array); \/\/same join\n\nTokenizing\n$str=\"fred,flint,35,wilma\";\n$token=strtok($str,\",\");\nwhile($token != false){\n echo (\"$token \");\n $token = strtok(\",\");\n}\n\/\/ fred flint 35 wilma\nsscanf(str,temp[, var1,var2...]);\n\nString search\nstrpos(large_str, small_str);\nstrrpos(large_str, small_str);\nstrstr(large_str, small_str);\n\nDecompose url\n$array=parse_url(url);\n\nArrays<\/strong>
\n-define
\n $person[0] = ‘Edison’;
\n $person[‘1’] = ‘Wankel’;
\n $person = array(
\n ‘Edison’,’Wankel’);
\n $person = array(
\n ‘0’ => ‘Edison’,
\n ‘1’ => ‘Winkel’);
\n-use
\n foreach ($person as $name){
\n echo “Hello, $name\\n”;
\n }<\/p>\n

Class<\/strong><\/p>\n

Define Class
\nclass Person {
\n var $name = ”;
\n function name($new = null) {
\n if (! is_null($new)){
\n $this->name = $new;
\n }
\n return $this->name;
\n }
\n}<\/p>\n

Use Class
\n$ed = new Person;
\n$ed->name(‘Edison’);
\nprintf(“Hello, %s\\n”,$ed->name;<\/p>\n

Operators<\/strong>
\n-Arithmetic
\n +
\n –
\n *
\n \/
\n %
\n ++
\n —
\n-Assignment
\n =
\n +=
\n -=
\n *=
\n \/=
\n %=<\/p>\n

-Comparison
\n ==
\n === \/\/ of same type
\n !=
\n !== \/\/ of same type
\n >
\n <\n >=
\n <=\n\n-Logical\n &&\n ||\n !\n\nCondition<\/strong>
\n-if
\n if (condition) {
\n statements;
\n }else{
\n statements;
\n }<\/p>\n

-switch
\n switch (expression) {
\n case label1:
\n statements;
\n break;
\n case label2:
\n statements;
\n break;
\n default:
\n statements;
\n break;
\n }<\/p>\n

Looping<\/strong>
\n-while
\n while (condition) {
\n statements;
\n }<\/p>\n

-do while
\n do {
\n statements;
\n } while (condition);<\/p>\n

-for
\n for (int i=0; i<5; i++) {\n statements;\n }\n\nexit and return<\/strong>
\n-exit(“db fail”);
\n-die(“db fail”);
\n-$db = @mysql_connect(“localhost”, $USERNAME,$PASS)
\nor die(“db fail”);<\/p>\n

Include code<\/strong>
\n
\n
\ncontent
\n
\n-allow_url_fopen in php.ini
\n-include_once\/require_once
\n-qet_included_files()<\/p>\n

Embedding in web pages<\/strong>
\n-Use echo<\/p>\n

\r\n\r\n<\/pre>\n
-Use PHP Script<\/p>\n
\r\n