: This article mainly introduces php programming notes. if you are interested in PHP tutorials, please refer to them. Three methods for php to obtain POST data 
Php image watermarking source code 
Php + ajax + json is the simplest example. 
Php Chinese character to pinyin source code 
Php traverses the Directory, generates the md5 value of each file in the directory, and writes it to the result file. 
Php implements the linux command tail-f 
Php json_encode and json_decode use instances 
Php curl simulates logon and obtains data 
Php fprintf writes formatted strings to the stream 
Php explode splits strings into arrays 
Php crc32 calculates the 32-bit CRC of a string (cyclic redundancy check) 
Php count_chars returns the string's character information 
The php convert_uuencode function uses uuencode to encode a string. 
Php convert_uudecode function decodes uuencode-encoded strings. 
Php ternary operators 
Example of php ternary operators 
Difference between php const and define 
Php Call to undefined function curl_init () in E:/w 
Php display_errors enable debugging 
Php static const define variable differences 
Php uses fopen and file_get_contents to read file instances 
Php converts the excel numeric format to the date format 
Php convert_cyr_string converts a string from one Cyrillic character set to another 
Php chunk_split string segmentation function 
Php chr obtains the characters corresponding to the ASCII value. 
Php chop deletes spaces or other predefined characters on the right of the string. 
Php bin2hex converts ASCII characters to hexadecimal values 
Php addslashes add a backslash before the predefined characters 
Php addcslashes uses the backslash to escape characters in a string 
Php function explanation and analysis 
Php process control examples such as if, switch, while, for, and break 
Php operators and expressions 
Php foreach 
Php array merging array_merge and array_merge_recursive 
Difference between single quotation marks and double quotation marks defined strings in php 
Php get_class get_class_methods get the current class name and function name 
Php magic constant example 
Php switch usage example 
PHP clears the space code at both ends of all strings in the array 
Differences between value assignment and reference assignment in php 
Explanation of variable reference and destruction mechanism in php 
Difference between php die () and exit () 
Php code to get the file suffix 
Special usage of php this 
Usage of referenced symbols (&) in php 
Difference and usage of php isset () is_null () empty () 
Collect and organize common php functions 
PHP and jquery display the number of online users in real time 
Several methods for php to determine whether the array is empty 
Php file Upload 
PHP namespace instance details 
PHP implements an efficient database 
Php implements the Hash table function 
Php analyzes the cause of invalid Session 
Several methods to replace php mobile phone numbers with asterisks * 
Php deletes and sorts repeated values in the array 
Php COOKIE does not refresh and takes effect immediately 
PHP file_put_contents write files 
PHP determines the city and other information based on the IP address 
Use php with mysql to register an instance 
Php usort () sorts arrays through user-defined comparison functions 
Php uksort sorts the key names in the array 
Php uasort sorts the values in the array 
PHP anonymous functions and considerations 
PHP5.6 example of new CONST features 
How does php disable the eval () function? 
Php new self () keyword usage 
Differences between static and common variables in php 
Php shares two methods to get the file suffix 
Php uniqid mt_rand generates random non-repeated strings 
How does php obtain the last day of last month? 
Several methods for deleting a session in php 
PHP Closure class usage and introduction 
Php date_parse function example 
Php date_parse converts time to seconds 
Php sort function to sort arrays in ascending order 
Php shuffle array random sorting 
Php rsort sorts arrays. 
The php reset () function points internal pointers to the first element in the array and outputs 
The php range function creates an array containing a specified range unit. 
The php prev function obtains the value of an element on the array. 
The php next function outputs the value of the next element in the array. 
Php natsort sorts arrays 
Php natcasesort sorts arrays by case-insensitive letters 
Php list () assigns values to a group of variables with elements in the array. 
Php ksort sort the array in ascending order by key name 
Php krsort sorts arrays in descending order by key name 
The php key function obtains the key name of the current element in the array. 
Php in_array () check whether a value exists in the array 
Php array processing function extract (the array key name is used as the variable name, and the array key value is used as the variable value) 
Php end obtains the value of the last element of the array. 
Php each returns the current key-value pair in the array and moves the array pointer one step forward. 
Php current gets the current unit value in the array 
Php count gets the number of elements in the array 
Php compact creates an array using a variable (using the variable name as an array index and the variable value as an array value) 
Php asort sorts the array values in ascending order of letters or numbers and maintains the index relationship. 
Php arsort sorts the array values in descending order by letters or numbers 
Php array_walk applies user-defined functions to each element in the array 
Php array_walk_recursive uses a custom function to process each element in the array. 
Php array_values returns all values of the array. 
Php array_unshift inserts a new value into the beginning of the array 
Php array_unique deletes repeated values in the array 
Php array_uintersect calculates the intersection of arrays 
Php array_uintersect_uassoc calculates the intersection of arrays 
Php array_uintersect_assoc calculates the intersection of arrays 
Php array_udiff compares the key values of the two arrays and returns the difference set. 
Php array_udiff_uassoc with index check to calculate the array's difference set 
Php array_udiff_assoc calculates the difference set of two arrays 
How to use the wp_title () function in WordPress 
Php strstr () obtains all characters after a specified string 
PHP substr_count () obtains the number of occurrences of a substring. 
Differences between PHP strcmp () and strcasecmp () 
Setting enhanced configuration class instance of CI (Codeigniter) 
How to use the public platform development mode for php to achieve multi-Customer Service 
Yii method for adding default values to model (two methods) 
Yii cache cleanup method 
Joomla database operation Sample code 
Php getimagesize the length and width of the uploaded image detection code 
Simple PHP code for uploading and deleting images 
Php ajax example code for refreshing Upload of images 
Php uploads images to generate thumbnails (GD Library) 
Differences between sprintf and printf functions in php 
Php array_sum calculates the sum of all values in the array 
Php array_splice deletes part of the array and replaces it with other values. 
Php outputs json and displays Chinese characters in json 
Use difference between php time and date 
Php calculates the number of days, hours, minutes, and seconds in different time ranges. 
Write sessions to the database in thinkphp 
Php sends emails using smtp protocol 
Php array_slice extracts a sequence from the array 
Php array_shift deletes the first element in the array. 
Php array_search searches for the specified value in the array. 
Php array_reverse returns an array in reverse order 
The php array_replace function replaces the element of the first array with the passed array. 
Php UTF-8 and gb2312 automatic conversion 
Php shares a function for recursive file traversal. 
Php several methods to prevent repeated submission of forms 
Php ffmpeg specifies a frame as an image for video capturing. 
Php http authentication 
Php mysql user registration source code 
Php complete Cookie login source code 
Php mysql user logon source code 
Php array_replace_recursive recursively replaces the value of the first array with the value of the following array 
Php array_reduce () iterates the array into a single value using the callback function. 
Php array_rand randomly retrieves one or more values from the array 
Php array_push () adds one or more elements to the end of the array. 
Php array_product calculates the product of all values in the array. 
Php array_pop deletes the last element of the array. 
$ _ SERVER environment details 
Php urldecode decodes the encoded URL string 
Php urlencode encode the string with a URL 
Php shares a string encryption and decryption function 
Php Converts URL encoding for UTF-8 and GB2312 
Conversion between UTF-8 and GB2312 encoding in php 
Php judges whether the string is UTF-8 or gb2312 
Php array_pad fills the array to the specified length 
Php intercepts UTF-8 strings 
The php set_include_path function sets the include_path configuration option. 
Descriptions of DIRECTORY_SEPARATOR constants and PATH_SEPARATOR constants in php 
Php uses PATH_SEPARATOR to determine the current server system type 
Php array_multisort sorts arrays 
Php array_merge array merging 
Php array_merge_recursive combines two or more numbers into an array 
Php shares an operation (add, delete, modify, and query) mysql database class 
Php array_map uses a custom function to process each value in the array. 
Php array_keys returns the key name of the array 
Php checkbox multi-choice box is selected by default. 
Php retrieves the value of the checkbox check box 
If php submits a form on this page, how do I remember the value of radio single queue? 
How does php obtain the value of radio single queue? 
Difference between php array_key_exists () and isset () 
Php array_key_exists checks whether a key name or index exists in the array. 
Php array_intersect calculates the intersection of arrays 
Php uses iframe to upload files without refreshing 
Php uses html5 FormData for refreshing file uploads 
Php uses html5 for multi-file Upload 
Php multi-file Upload implementation 
Php modifies the size limit of uploaded files 
Php file Upload instance 
Php is_uploaded_file () determines whether the specified file is uploaded through http post. 
Three methods for transferring values between php pages 
Php uses input hidden to pass value to an instance 
Php array_intersect_ukey uses the callback function to compare key names to calculate the intersection of arrays. 
Php array_intersect_uassoc use user-defined functions to calculate the intersection of two arrays 
Php array_intersect_key uses the key name to calculate the intersection of arrays 
Php array_intersect_assoc compares the key names and key values of the two arrays and returns the intersection 
Php array_flip reverses the keys and values in the swap array 
Php array_filter function example 
Three methods for PHP to simulate post submission 
Php uses curl to simulate post submission 
Php uses fsockopen to simulate form post submission 
Php form $ _ POST [] instance application 
How does php obtain the multiple value of the select multiple-choice box? 
How does php obtain the selected value from the select drop-down list? 
A select option set in php is selected. 
How does a PHP custom function return multiple values? 
Php array_fill fills the array with the given value 
Php array_fill_keys () fills the array with the specified key and value 
Php extract treats the name of the form element as the variable name and the value of the element as the variable value. 
Submit the php form to this page 
How does php determine which values of the multiple checkbox boxes are selected? 
Php checks whether the checkbox is selected 
Php checkbox multiple selection box and pass value 
Php mail (cc and bcc) 
Php array_diff function usage 
Php array_diff_ukey () function 
Php array_diff_uassoc () function instance 
Php form instance application 
Php simple file Upload instance 
Introduction to php array_diff_key () function instances 
PHP array_diff_assoc () function example 
Php array_count_values () function example 
Php array_combine function example 
Php array_column function instance application 
Php array_chunk () function instances and applications 
Php array_change_key_case function instances and applications 
Php cookie instance 
Php mysql_select_db instance 
Php substr_count: number of times a string appears in another string 
How PHP intercepts Chinese Strings 
Php simplexml parsing xml 
Php regular expression function example 
How php Converts Word documents to pdf 
Php mail () function user instance 
Php mail configuration method 
Php ajax asynchronously reads rss document data 
Php file Upload instance 
Php ajax without refreshing file Upload instance 
Php cookie application instance 
Php preg_match function and php preg_match_al function l instance, method, example 
Php preg_match_all () function instance 
Php preg_match regular expression function instance 
Php ajax XMLHttpRequest instance 
File upload progress bar implemented by php ajax 
Php $ _ SESSION member logon instance 
Php array functions 
Php cannot output xml with Chinese characters 
Php string uppercase/lowercase 
 
The above introduces the php programming notes, including some content, and hopes to help those who are interested in the PHP Tutorial.