Section 1
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what are the seven main error reporting constants?
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Cards (154)
Section 1
(50 cards)
what are the seven main error reporting constants?
E_NOTICE, E_WARNING, E_PARSE, E_ERROR, E_ALL, E_STRICT, E_DEPRECATED
will print $_GET work? why or why not?
no, because you cannot use the print function on arrays.
what type of variable is $_POST?
predefined variable.
can variable names begin with underscores?
yes.
what is the first argument of the number_format() function?
the number or numeric variable to be formatted.
are variable names case-sensitive?
yes.
what should be used to have multiple quotations in one string?
the escape character '\': $string = "I said \"Hello\" to the man.";
what will error_reporting (E_ALL | E_STRICT) do?
it will show all errors that fall under E_ALL or E_STRICT, the pipe | is used for 'or' so that errors that fall under either will be shown; E_ALL & E_STRICT would be incorrect for this purpose because the error would have to fall under both E_ALL and E_STRICT.
how do you know what to use to get a value from POST or GET?
they are the values of the name attributes of the input tags in the form. $_POST['name'] or $_GET['name'] refers to the value of <input name="name" /> (depending on the method of the form).
what are the four main error types?
Notice, Warning, Parse error, and Error.
what can be used to print data in an array?
not print; print_r (human readable) can be used.
what is the default number of decimals that round() will round to?
no decimals, it will round to the nearest integer.
describe the error type 'Notice'
Notice is not fatal, but may or may not be indicative of a problem: referring to a variable with no value.
will print $_SERVER work? why or why not?
no, because you cannot use the print function on arrays.
when should you use double quotes?
when a variable contains any amount of variables; in general.
what will error_reporting (E_ALL) do?
it will show all error reporting.
what type of variable is $_SERVER
$_SERVER is a predefined variable.
is data shown in the URL if POST is used?
no; use for passwords, pages that would not be bookmarked, pages that require security.
what are some basic arithmetic operators?
+ addition - subtraction * multiplication / division
where is data sent using POST found?
predefined variable $_POST
how can you set up error reporting?
with the function error_reporting();
can variable names begin with numbers?
no.
what is the optional second argument of the round() function?
the number of decimal places to round to. round(12.4958670, 3) will yield 12.496
what function can you use to format a number with commas?
number_format()
what can you use to display errors in a particular script?
ini_set ('display_errors', 1); should be placed at top of script.
besides GET and POST, what other predefined variable can you use to access data?
$_REQUEST, but $_POST and $_GET are more precise, and therefore preferable.
why should you use comments before you shorthand variables for POST and GET?
so you know which values are being passed from the form. // feedback.html passes title, name, email, response, comments $title = $_POST['title'] ...
how can you put a dollar sign before a variable like $10 where 10 is the variable's value?
you can escape the first dollar sign; \$$cost; or you can use curly braces; ${$total}
describe the error type 'Warning'
Warning is not fatal, but is probably problematic: misusing a function.
what is the first argument of the round() function?
the number or numeric variable to be rounded.
what is an 'index' or 'key'?
what is referred to for a value within an array. $_POST['name'] may be equal to 'Jane Doe' $cards[4] may be equal to 'BMW'
what is the round() function used for?
to round numeric values.
when should you use single quotes?
when there are no variables in the string; if you use single quotes, PHP will not search for variables to replace, which can enhance speed.
what types of arguments are used for error_reporting()?
predefined constants that are not in quotations.
can a string with numbers be used as a number?
yes. $string = "2"; can be used as $string = 2; can be used.
what will error_reporting (E_ALL & -E_NOTICE) do?
it will show all error reporting except for notice errors.
can arrays contain arrays?
yes, they commonly do contain arrays.
what will happen if $_POST['name'] is used in double quotes?
a parse error will occur, to avoid this, create shorthand variables like: $name1 = $_POST['name1']; $name2 = $_POST['name2'];
describe the error type 'Error'
Error is fatal, it is a general fatal error: memory allocation problem.
what type of variable is $_GET?
predefined variable.
what is the second optional argument of the number_format() function?
the number of decimal places to round to. number_format(125939.4958670, 3) will yield 125,939.496
where is data sent using GET found?
predefined variable $_GET
what should the action attribute's value contain?
the URL to the php script that will handle the information in the form.
can variable names contain symbols?
no.
what character must all variables begin with?
the dollar sign $.
what will error_reporting (0) do?
it will not show error reporting, it will be turned off.
is data shown in the URL if GET is used?
yes; use for search engines, catalogued pages, pages that would be bookmarked.
what can the number_format() function be used for? (two answers)
the function will format with commas and the second argument can determine how many decimals to round to.
describe the error type 'Parse error'
Parse error is fatal, caused by a semantic mistake: omission of a semicolon, imbalance of quotations, parentheses, or braces.
will print $_POST work? why or why not?
no, because you cannot use the print function on arrays.
Section 2
(50 cards)
is round($num) the same as round ($num)
yes, spaces are optional and not required after a function.
how many arguments can isset() take?
any amount.
what if you want to use trim() for the beginning of a string?
you can use ltrim() (as in left-trim), because the left is the beginning of the string.
what is a control structure?
a conditional or loop.
what can you use to case-sensitively replace substrings with other strings?
str_replace()
what can strlen() be used for?
to find the length of a string; strlen('Hello, world!') would yield 13
what can strip_tags() be used for?
removes all HTML and PHP tags.
what can empty() be used for?
to check if a given variable has an "empty" value - no value, 0, or FALSE.
what can wordwrap() do?
word wrap after a certain amount of characters.
what can str_word_count() be used for?
to find the amount of words in a string.
what function can be used to find the absolute value of a number or numeric variable?
abs()
what can trim() be used for?
to remove any white space - spaces, newlines, tabs - from the beginning and end of a string, not the middle.
what are the first and second optional arguments of rand()?
the lower limit and the upper limit for $num = rand(0, 10) $num must be between 0 and 10.
what can strtok() be used for?
to create a substring (referred to as a token) from a larger string; $first = strtok($_POST['name'], ' ') finds first name because first and last name is separated by a space.
what can is_numeric() be used for?
to check if a variable has a valid numerical value; strings with numerical values pass.
define precedence
the order of operations.
what can htmlentities() be used for?
converts all HTML tags into their entity versions. <span> -> <span>
what tag begins a php script?
<?php
what happens if you omit the third argument of substr()?
the substring will contain the rest of the string starting at the index value provided by the second argument.
what number do indices begin at?
zero, and they continue to the length of the string minus one.
what can crypt() be used for?
to encrypt values; it is a one-way encryption method, but you can compare $data to crypt($string), if, say, $string is a password as user has entered and $data is the password on file.
what shorthand can you use to increment? decrement?
$var++ and $var-- respectively.
what function can be used to round down to the lowest integer?
floor()
can parentheses be used in conditional statements to set precedence?
yes.
what tag ends a php script?
?>
list some comparison operators
== equality != inequality < less than > greater than <= less than or equal to >= greater than or equal to
can negative numbers be used with substr() to count backward?
yes.
what counters htmlentities()?
html_entity_decode()
what can isset() be used for?
to check if a variable has any value (including 0, FALSE, or an empty string). $var1 = 0; $var 2 = 'something'; isset(var1); // TRUE isset(var2); // TRUE isset(var); // FALSE
what function can you use to create a random number?
rand() function.
what can urldecode() be used for?
when applied, the value is decoded from its encoded nature; firstname+last name -> firstname lastname.
what can str_ireplace() be used for?
to replace a substring with another string; $me = 'first i. last'; $me = str_ireplace('i.', 'initial', $me); print $me; // 'first initial last' it is not case-sensitive.
what will happen if there are no numbers to round? round (12, 2)
zeros will be added to the end.
what will strip_tags(nl2br($string)) do?
nl2br will replace any new lines in $string with <br /> tags, and then strip_tags will remove any HTML or PHP tags, including the just inserted <br /> tags; use nl2br(strip_tags($string)) instead.
how does round() handle 0.5, 0.05, etc. rounds?
half the time it rounds up, half the time it rounds down.
what number do indices end at?
the length minus one, and they always begin at zero.
what is the concatenation assignment operator?
.= $greeting = 'hello, '; $greeting =. 'world!'; $greeting yields 'hello, world!'
what can urlencode() be used for?
when applied, the value can be passed safely through the URL (GET).
what is the function getrandmax() for?
it contains the highest value that rand() can have randomly
what operator can you use to find the remainder of $x divided by $y?
$z = $x % $y; $z will yield the remainder of $x / $y
what is the nl2br() function used for?
to convert new lines in a variable from a form to <br /> tags so that the data can be formatted correctly.
what is the concatenation operator?
the period; .
what can htmlspecialchars() be used for?
it converts certain HTML tags into their entity versions. <span> -> <span>
what if you want to use trim() for the end of a string?
you can use rtrim() (as in right-trim), because the right is the end of the string.
what can substr() be used for?
to find a substring in a larger string using indices; $sub = substr($string, 2, 10) assigns $sub ten characters of $string starting at the second character of $string.
what two conditionals does PHP have?
if and switch.
what function can be used to round up to the highest integer?
ceil()
define concatenate
to append; add a string to the end of another string.
what operators can you use to operate and assign?
+=, -=, *=, /= $num += 5 will yield $num + 5 $num /= 5 will yield $num / 5
list some logical operators
! negation AND and && and OR or || or XOR or not
Section 3
(50 cards)
what are the seven main SQL functions?
alter - modifies existing table; create - creates database or table; delete - deletes records from a table; drop - deletes a database or table; insert - adds records to a table; select - retrieves records from a table; update - updates records in a table;
what are the three types of loops in PHP?
for, while, foreach.
how do you create an array?
with the array() function; $groceries = array('apples', 'bananas', 'oranges'); first element is assigned key 0 by default.
how can you sort the values while maintaining the correlation between each value and its key?
the asort() function; arsort() can be used for reversed order; asort($array);
what is the for loop designed to do?
to perform specific statements for a determined number of iterations
how can you iterate over the values of an array?
for ($i = 0; $i < count($array); $i++) {statement(s);}
what function can be used to get time data?
the date() function; date('formatting').
what does ksort() sort by?
keys; key-values maintained.
how can you sort by the keys while maintaining the correlation between the key and its value?
the ksort() function; krsort() can be used for reversed order; ksort($array);
does rsort() maintain key-values?
no.
what do natsort() and natcasesort() do?
they sort using natural order while maintaining key-value; name2 is placed before name12; sort() would place name12 before name2.
what does rsort() sortby?
reversed values; key-values not maintained.
what can you do to delete an element of an array?
use the unset() function; unset($array[7]);
how can you assign keys to the values in an array?
with the array() function; $groceries = array(1 => 'apples', 2 => 'bananas', 3 => 'oranges'); $groceries = array( 1 => 'apples', 2 => 'bananas', 3 => 'oranges' ); the key does not have to be a number.
what is a superglobal
$_SERVER, $_POST, $_GET, $_COOKIE, $_SESSION, $_ENV; special arrays.
what is the while loop designed to do?
to run until a condition is FALSE; for (initial expression; condition; closing expression) {statement(s);}
how do you refer to an element in a multidimensional array?
listing the indices in order of general to more precise; $meats = ('turkey', 'ham', 'chicken'); $vegetables = ('broccoli', 'lettuce', 'tomato'); $foods = array($meats, $vegetables); print $foods[1][1]; // lettuce print $foots[0][0]; // broccoli
how can you discern if a constant is already declared?
by using the defined() function; defined('CONSTANT'); usually used with conditional statements.
how can you iterate over the keys and values of an array?
with the foreach loop; foreach ($array as $key => $value) {statement(s);} foreach ($array as $k => $v) {statement(s);}
what function can you use to find how many substrings are in a string?
the substr_count(); substr_count($_POST['email'], '@') // counts @ signs in $_POST['email']
how do you declare a constant?
by using the define() function; define ('CONSTANT', value); constants are usually capitalised, but do not have to be; you DO NOT use dollar signs - they are constants not variables.
what control structure does break exit?
if/elseif/else and switch statements.
does arsort() maintain key-values?
yes.
how can you sort values of an array without regard to the keys?
the sort() function; rsort() can be used for reversed order; sort($array);
what does sort() sort by?
values; key-values not maintained.
how can you convert an array into a string?
with the implode() function; join() also works; $string = implode(glue, $array);
does sort() maintain key-values?
no.
does asort() maintain key-values?
yes.
what can you use to merge arrays?
the function array_merge(); $new_array = array_merge($array1, $array2); or you can use the + or += operators appropriately: $soups = $soups + $soups2; $soups += $soups2;
what is an indexed array?
an array whose keys are numbers.
does krsort() maintani key-values?
yes.
how can you iterate over the values of an array, but not the keys?
with the foreach loop; foreach ($array as $value) {statement(s);}
how can you convert a string into an array?
with the explode() function; $array = explode(separator, $string);
what can you do to determine the amount of elements in an array?
use the count() function; $howmany = count($array);
what is an associative array?
an array whose keys are strings; also known as a hash.
what can you do to delete a variable?
use the unset() function; unset($var); unset($array[7]);
how can the list() function be used?
to assign array element values to individual variables; $date = array('Thursday', 23, 'October'); list($weekday, $day, $month) = $date; now a $weekday, $day, $month variable exist, with respective values; must be indexed, beginning with 0; arguments cannot be omitted but can be ignored; list($weekday, ,) = $date;
what does asort() sort by?
values; key-values maintained.
how do you append elements to an array?
$array[] = item; will assign item to the next available index; associative arrays get messy.
what does SQL stand for?
structured query language.
how can you create an array with an HTML form?
by making the name attribute equal to the name of the array, and the value equal to the value of an element of the array; this makes $_POST or $_GET multidimensional.
what can you do to reset an array?
reassign the array() function to the array; $array = array();
what functions can you use to include files?
include() and require(); include() will give errors, require() will terminate execution().
what control structure does continue exit?
loops; any statements after the continue are not executed, but the condition of the loop is checked again afterward.
what does krsort() sort by?
reversed keys; key-values maintained.
how can you reorganise the array randomly?
the shuffle() function; shuffle($array);
if you are worried about quotation marks while using arrays, what should you use?
curly braces; print "<p>Monday's soup is {$soups['Monday'[}.</p>";
does ksort() maintain key-values?
yes.
how do you refer to an item in an array?
$varname[key]; keys can be numbers or strings.
what does arsort() sort by?
reversed values; key-values not maintained.
Section 4
(4 cards)