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Section 1
(50 cards)
number of first character in string or first item of an array in PHP
0
PHP substr();
-gets passed a string or var containing a string -allows you to return a substring of another string substr($var, number to start at, how many to go forward with);
PHP foreach loops purpose
walk through an elements of an array or object one by one
PHP strtolower();
-changes string to lowercase
PHP array_sum();
-sum from an array that will return it's value
PHP end of code line is signified by
;
PHP trim();
-remove excess white space before and after string, not in between words
PHP sort():
-sort array by order, modifying the array in the process
format of PHP FOR loop
for ($var = 2004; $var < 2000; $var = $var + 2) { echo text; } OR SHORTHAND for ($var = 2004; $var < 2000; $leap++;) {echo text; } these variables are basically, the start point, the condition at which to check every time, and what to run at the end of each loop or iteration
PHP remove array
unset($array);
how to increase by 1 php
++
what code stops a code block once running in PHP
exit;
cocatenation operator in PHP
.
PHP foreach format
foreach ($array as $element) { echo "$element"; }
PHP strpos();
-finds position of the occurrence of a substring in a string
number of first character in a string PHP
0
PHP strtoupper();
-changes string to uppercase
PHP server or client side?
server side
PHP rand();
-produces a random number between two numbers -rand(min, max);
stating tags of PHP
<?php
do you put quotes around numbers in PHP
no, only strings (not including booleans)
PHP when to use foreach vs while loops
foreach would be best used with arrays and objects while loops can be used for data of a different datatytpe or initialized data
when do you use quotes for variables in PHP
for strings, not numbers or boolean values
PHP count();
-count number of items in an array -pass it an array
PHP round();
-rounds a number to decimal place -round(number, number of decimal places)
PHP for loops purpose
good for running loops if you know how many times you are going to run a loop
PHP change item in list of array
$array[3] = 'newitem';
PHP strlen();
-gets passed a string or var containing a string -returns number of characters in a string
PHP array_push();
-adds an element to an array -array_push(array, element to add to array);
do you always have to use both starting and ending tags for PHP?
don't have to use the ending tag if there is only PHP In the document (No HTML)
comparison operators in PHP
> = greater than < = less than <= is less than or equal to >= is greater than or equal to == is equal to != is not equal to
PHP htmlspecialchars();
-treats input as regular text, not HTML.. achieves this by ESCAPING THE TEXT
PHP for vs foreach loop
for is technically faster than foreach for normal array loops, but not a good reason to use it because it still has bad usability. foreach is much easier to read and great for walking through elements of an object or array. you should really only use for loops when you need to change the counter during an iteration foreach also is able to access associative arrays, while for is not
javascript server or client side?
client side
PHP join();
-glue array items together by : -does not actually modify the array, just returns the value and must be used with echo or print in that case -join(":", $array);
PHP header();
-redirect to another page -header("Location: contact-thank-you.php");
how to comment in PHP
//
while vs do while loops PHP
do while loops you can run a do statement block of code before the loop
what do you put quotes around in PHP
strings, not numbers, not booleans
PHP types of loops
1) FOR loops 2) FOREACH loops 3) WHILE loops 4) DOWHILE loops 5) IF loops 6) IF/ELSE loops
how to echo array item in php
$array[2]; will show the 3rd item $array{2}; this also works
what does 1 and 0 mean in php
true, false
PHP rsort():
-sort array by opposite order, modifying the array in the process
two syntaxes of switch PHP
1) switch (a) { case 1: echo "test"; break; default: echo "default"; } 2) switch (a): case1: echo "test"; break; default: echo "default"; endswitch;
PHP var_dump();
-shows all the possible information about a variable including arrays
why use a switch instead of if/else PHP
switch only accepts certain constant datatypes, while if else accepts all switch can fall through to the next if the break between two switches is forgotten, whereas with if/else you can't forget the break between two statements you can leave the else in if else switch is more compact can't use comparison operators in switch
PHP remove an item from an array
unset($array[2]);
ending tags of PHP
?>
format of while loops PHP
while(cond) { // looped statements } while($i<10) { echo "$i"; $i++; } ALTERNATE: while(cone): { echo "$i"; $i++; } endwhile;
all variables in PHP start with
$
Section 2
(50 cards)
PHP ceil();
-rounds integer up
PHP is_a();
check if a given instance (the first variable passed) is part of a given class (the second variable passed is_a($me, "Person");
PHP array_shift():
-removes one value from an array, returns the one value that was removed if stored in a variable
PHP floor();
-rounds integer down
purpose of constructor in PHP
in order to force data to be given to object when it is instantiated as an instance and disallow any instances without such data, this allows for it to be loaded right away with initialization if you need the data to be for other methods to function correctly for example
PHP $_SERVER and example of use
-array -REQUEST_METHOD can be used to check request method
PHP method_exists;
check if an object has a given method ($me, "Person");
when you are improving the code PHP without changing the functionality what is that called
refactoring
PHP array_reverse();
-reverses the array and makes new keys starting from 0
rewrite links are found in
.htaccess
how to make a variable that doesn't change in PHP
make a constant cont alive = true; **don't use $ for the variable
PHP how do you create objects?
from classes $obj1 = new Class;
how to access in php multidimensional arrays
$assoarray[2][1]
how to make an non override able inheritance method? PHP
use final keyword final public function drive() {}
PHP $_GET
-an array usually formed by a URL submission
PHP associative arrays format
$assocarray = array('Swag' => 1, 'Swag2' => 2);
how to make a rewrite rule in htaccess
RewriteRule (URL YOU ARE REFERENCING) (WHAT URL TO LOAD) sooo RewriteRule ^shirts/$ /shirts/shirts.php
php what are these in php associative arrays X => Y
key => value
can the first number of a PHP variable be a number?
NOPE
do you always need both opening and closing PHP tags
only need opening tag if all the code in the document is PHP
PHP empty();
checks if an array is empty.. if empty is returns boolean true
PHP how to return a value within a statement without actually displaying it
return();
do search forms in PHP use GET Or POST
GET
in htaccess how to redirect and tell the search engine that it is a permanent effect
add [R=301] to the end of a redirect
PHP $this
allows you to access properties in a class
how to check request method in PHP
$_SERVER['REQUEST METHOD']
how do you access static variables in PHP
:: if(Class::$variable) {}
MVC PHP
MODELS --> page that contains data VIEW --> page when it displays content CONTROLLERS --> determines which methods to call from models
standard naming of html partials
partial-name.html
how do you use $this to access a property
$this->obj1 **dont use the $ on the variable when accessing it
in htaccess what does the $ mean
it means the end of a url
in htaccess what does ^ mean
everything before, the root url basically before the htaccess file
PHP instance vs objects
instantiated objects, they become things instead of just definitions
how to access associative array values
assocarray[key];
htaccess how to check for a GET request
use RewriteCond with the following to check for different numbers then write a query string like the following: %{QUERY_STRING} ^id=[0-9]+$ the + sign means that any number of characters is fine
PHP intvalue();
-if integer, returns boolean true
PHP objects contain
methods(functions) and properties(variables)
what to start htacess with
ReWriteEngine On --> turns rewrite engine on
php what is the point of the using a static keyword
when you want to use a method or variable that is not tied to an instance
are PHP variables case sensitive?
yes
how do you access constants in PHP
you use the :: with Class::constant if(Class::constant) {}
PHP $_POST
-array made through form submissions
what signifies end of commands in rewrite links of htacess
nothing, just paragraphs
purpose of pre tags in PHP
to show whitespace in browser (preserves both line breaks and spaces in browser)
PHP property_exists;
check if an object has a given property
what are html Partials
small snippets of code that are reused
PHP what are instances
objects within classes
types of links in PHP
1) relative links (uses ../ and folder refs) 2) absolute links (use http) 3) root-relative links ( start with / and starts at the root) 4) constants which can have a variable that defines the base url and then append the end of the url on (BASE_URL and ROOT_URL) concatenated with other directories 5) absolute server links --> use /User/Desktop etc for desktops and $_SERVER["DOCUMENT_ROOT"] for web servers
what is scope resolution operator in PHP
accessing static and const in PHP using ::
php what differentiates static and const variables
const are always public, whereas static are default public unless specified static variables can be changed
Section 3
(50 cards)
what does it mean that PHP is WEAKLY TYPED
it doesn't really care what type of data you store in a variable
fatal error in PHP
HTML prior to the error will be displayed, but everything after won't be CAUSE --> referring to a nonexistent file or function
do quotes have to be matching in PHP strings
yes
PHP combined assignment operators
$a += $b is equal to $a = $a + $b
how to subtract in PHP
-
how to add PHP comments
1) // 2) # 3) / /
when you are using too many escape sequences in PHP, what might the better option be?
to use HEREDOC SYNTAX
inequality in PHP
!=
what is the number of a value in a regular array called
key
$_SERVER php
get information from the web server
strict error in PHP
warns about techniques that are not considered good practice
what does = mean in PHP
assignment operator
recoverable error in PHP
occurs when an exception error is thrown
anything between DOUBLE quotes in PHP is treated as
regular text
escape sequences that can process variables and special characters
1)
--> insert new line char
2) \r --> inserts carriage return
3) \t --> inserts tab
what is modulo division in PHP
use % and it will return the remainder of the division
$_GET php
get info passed via http get method
what does PHP determine as implicit false boolean value
1) keywords FALSE/NULL 2) 0, 0.0, '0', "0" 3) empty string '' 4) empty array
handling exceptions errors in PHP
use the built in PHP classes to auto throw a specific exception catch it with a separate code block after wrapping main script in a try block the catch block can redirect user to an error page
how to do AND in PHP
&&
how to use else if php
if (cond true) {//code} else if (second cond true) { //first false, second true} elseif {//both are false}
superglobal arrays in PHP all begin with
$_
$_SESSION php
to create simple login systems
$_POST php
get info passed via HTTP post method
how to get document root of your server in PHP
$_SERVER['DOCUMENT_ROOT']
how to increment +1 in PHP
++
identical in PHP plus what does it mean
=== means same value AND data type
parse error in PHP
mistake in code syntax, stops and doesn't allow for HTML output
how to force a variable to a specific type in PHP
$types = (array) $types; forced into an array type
warning error in PHP
serious problem such as include file missing, but rest of output is still processed
deprecated error in PHP
warning that features are scheduled to be removed in the next major version of PHP script COULD suddenly stop working in the future
8 data types of PHP
1) integer 2) float point number (decimal containing number) 3) string 4) boolean 5) array 6) object 7) resrouce 8) null
how to decrease -1 in PHP
--
equal sign in PHP
==
$_FILES php
to upload files to webserver
are boolean values (true/false/null) case sensitive?
no, they are case insensitive
how to divide in PHP
/
how to inspect an array in PHP and print the contents
print_r($array);
anything between SINGLE quotes in PHP is treated as
literal text
superglobal arrays PHP
built into PHP and are automatically populated with useful information, such as POST and GET
how to get the domain name of a website in PHP
$_SERVER['HTTP_HOST']
what can you do in PHP if there is punctuation in a PHP string
1) could use double quotes 2) could precede apostrophes with a backslash (escaping)
how to do OR in PHP
||
when to use single or double quotes PHP
single = all the time unless string contains variables
in PHP is the error usually where the line PHP discovered the problem?
no, most of the time PHP is telling you that something unexpected happened, and the mistake lies before that point
type of arrays PHP
index arrays associative arrays multidimensional arrays superglobal arrays
how to multiply in PHP
*
is there any points where you don't need to include a semicolon at the end of a PHP line?
if there is only one statement in a code block, but even then it is bad practice
how to add in PHP
+
notice error in PHP
occurs when you have a small issue such as usage of a non declared variable, and the page will still display
assignment operator in PHP
=
Section 4
(16 cards)