PHP Small Summary

<?PHP// 1.php Base syntax //Output statement echo print Print_r var_dump ()//2.php is a weakly typed language //cast type: (type) variable settype (variable, type)/ /3. Variable definitions $a= 5;//variable variable: $b = "a";   $ $b = 10;//Determines the variable type gettype (variable), gets the variable type Is_ type () Is_int (), determines whether the variable is the type//judgment variable is empty: empty (); Isset ()//delete variable: unset (); //4. How strings are defined $str= "Hello";//can parse escape characters and variables$str= ' Hello ';//escape characters and variables cannot be parsed$str= <<<Ahelloa;//don't worry about single and double quotes //5. Operator expressions (+-*/+ +--= etc.)//6. Statement //branch: If switch...case//loop: for foreach whi Le do...while//7. Functions //Four elements: return type, function name, parameter list, function body//definition of function in PHPfunctionShow ()//Normal{}functionShow$a)//there's a return.{}functionShow ()//has the default{    return $a;}functionShow$a=5)//has the default{}functionShow ()//variable-parameter{    Func_get_args();}//8. Commonly used functionsRandom number: rand (); Rand (0,10); random number between 0~10/datetime: Time (), can get current datetime timestamp//date (formatted string, timestamp); format datetime, y-m-d year-month-day h-i-s hour-minute-second Uppercase H is a 24-hour lowercase h is a 12-hour//strtotame (a string representing an event); Converts a string to a timestamp//9. OtherError suppressor @//Exit Program: Exit (); Die ("error message");//************************************************************************************************ ********//Two, the common method of string//1. Take the length of the string:Strlen ();//2. Splitting a string:Explode ();//3. Merging strings:Implode ();//4. Intercepting a string:SUBSTR ();//5. Replacement string:Str_replace (); Find replacement Substr_replace (); Specify location substitution//6. Go to space:Trim ();//7. Turn Capital:Strtoupper ();//8. Turn lowercase:Strtolower ();//9. Split by Length:Str_split ();//************************************************************************************************ Third, regular expression//1. Delimiter:/   ///2. Start of match:^ Match End $//3.\d any number \a an invisible character \w any number or word character + The preceding expression appears at least once {0,2} The expression preceded by at least 0 occurrences of the maximum occurrence of 2 times//[0,1,2] matches any character [0-9] matches the number between 0-9 [A- Z] matches a A-Z word character ()--priority |--or//4. Splitting a string:Preg_split ();//5. Replacement string:Preg_replace ();//6. Match the data that appears in the string (to satisfy the regular):Preg_match (); Preg_match_all ();//******************************************************************************************* Four, array//1. Array classification:By dimension: one-dimensional arrays and multidimensional arrays//based on index: indexed arrays and associative arrays//2. Array definitions$attr=Array();//Common definition methods$attr[] = 5;//Assignment definition//Definition index array: $attr = Array (1,2,3,4);//define associative array: $attr = Array ("Key" = "value");    //3. Value //indexed array: $attr [0]; Associative array value: $attr ["Key"]; //4. Iterating through an array://for loops, only traversing indexed arrays for($i= 0;$i<Count($attr);$i++){    $attr[$i];}//foreach traversal to facilitate indexed arrays and associative arraysforeach($attr  as $v){    $v;}//Each () and List () methods combineEach (): Returns the key and value of the current element inside the array, returning an array of form//list (): Assigns the value of the right array to a list of variables ($a, $b)//Pointer traversalTakes the value of the element pointed to by the current pointer: present ();    Key:key () of the element to which the current pointer is pointing;    Point the pointer to the next element: Next ();    Point the pointer to the previous element: prev ();    Resets the pointer: Reset (); Point the pointer to the last element: End ();//5. Common functions for arraysTake the array length: count ();//To add elements to an array: Array_push ();//Determine if an array contains an element: In_array ();//merge array: Array_merge ();//repeat: Array_unique (); /delete array element: unset ();//re-index: array_values ();//Flip array: Array_reverse ();//array element ordering: Array_multisort ();//******************** ***************************************************************************************//Five, object oriented OOP//1. Classes and ObjectsClasses are abstracted from many objects, and objects are instantiated from classes.//2. Definition of class:Class ren{}//Includes member variable member method constructor destructor __get () method __set () method __tostring () method __clone () method//3. Access modifiers:Public private privately owned protected protected//4. Three major featuresEncapsulation: Purpose approach//Inheritance: Conceptual feature function or method rewrite//polymorphism: Conceptual condition//5. Static:Statically static members belong to the class, and the ordinary members are the objects that belong to the//6. Abstract class:Abstract class cannot be instantiated, generally used as parent//interface interface can define methods but do not write function body//7. Cloning objects:Clone//8. Constructors:__construct () Special Execution Time Special//9. Loading Classes    include(""); include""; require(""); require""; require_once(""); require_once"";//Auto Load Class __autoload ();//10. Single-row modeControl class can only generate one object//11. Factory mode//************************************************************************************************************
//VI, data access//1.mysqli:$db = new mysqli (server, username, password, database);//mysqli_connect_error ();//Determine if the connection is successful//$result = $db->query (SQL statement);//$result Fetch_row ();//2.pdo$pdo = new PDO (DNS, username, password);//$stm = $PDO->prepare (SQL statement); Put this SQL statement on the server to wait for execution//$stm->excute ();//$stm->fetch_row ();//Can be used in SQL statements? To make a placeholder: a string placeholder//************************************************************************************************************
//Seven, Jquery Ajax  //1. Selector--$ ()Select $ ("#id") based on the ID to return a jquery object, take the DOM object from inside the jquery object to index 0[0]//select $ (". Class")////According to the attribute select $ ("[name=a]")// Signature Select $ ("div")//2. Operating contentManipulate non-form content: Text (); HTML code HTML ();//Manipulating form elements: Val ();//3. Action PropertiesAdd settings Property: attr (property name, property value);//Get Property: attr (attribute name);//Remove attribute: Removeattr (attribute name);//4. Operation StyleGet style: CSS (style name);//Add Setting Style: CSS (style name, style value);//5. Events$ ("#id"). Event name (function () {}),//$ ("#id"). Bind (event name, function () {}), bind event//$ ("#id"). Unbind (event name); Remove Event//6.ajaxAsync Asynchronous processing//url: Called Processing page//data: Data JSON format passed//type: How data is passed post or Get//datatype: Return data type text/json/xml//success: callback function// Error: A method that executes when an error is invoked//7.jsonFormat: {Key:value}//8.xml DocumentationFormat: Must have a root, and start must have end, case sensitive, tag name can be customized, you can add attributes//9. Session Control//session Features:
Stored on the server, there is a default expiration time, each user saves one copy, can store any type of data//must be turned on to use Session_Start (); must be written in the first line//$_session["UID"] = "List"; Pros: Security drawbacks: Seizing resources//cookiestored in the client by default is not the time period, each user saves one copy, only the string//setcookie (name, value), set cookie//$_cookie["UID"; Read COOKIE Advantage: No resource disadvantage: unsafe//*********** **************************************************************************************************
//Nine, file//1. File UploadDo file Upload form enctype//$_files Array read file information//control upload file format and size//build storage path (processing file name) to file name to create Folder//Determine whether the file exists//upload save Move_u Ploaded_file ();//transcoding format iconv (original code, target encoding, string);//2. File OperationsFile type: filetype () is_file () Is_dir ()//path:./current path. /parent Path/downlevel path//Traverse directory: Glob (); Returns all files in this directory, is a collection. New directory: mkdir (); Create a new directory//delete directory: RmDir ();//Mobile Directory: rename ();//New file: Touch ();//delete file: Unlink ();//Copy file: Copy ();//Get File Contents: FI Le_get_contents ();//write content: File_put_contents ();//File resources:Open File resource: fopen ();//Close File resource: fclose ();//Read file contents: fgetc (); read a fgets (); Read a row of fread (); Fwrite ();

PHP Small Summary