PHP Interpreter treats numbers beginning with 0 as octal.
PHP Questions and Answers
PHP is an important part of the web world, and every web developer should have the basic knowledge in PHP. Common PHP questions, which should help you become a best PHP developer.
May I use print “$a dollars” or “{$a} dollars” to print out the amount of dollars in this example?
In this example it wouldn’t matter, since the variable is all by itself, but if you were to print something like “{$a},000,000 mln dollars”, then you definitely need to use the braces.
How do you define a constant?
Via define() directive, like define (“MYCONSTANT”, 100);
How do you pass a variable by value?
Just like in C++, put an ampersand in front of it, like $a = &$b
When are you supposed to use endif to end the conditional statement?
When the original if was followed by : and then the code block without braces.
Explain the ternary conditional operator in PHP?
Expression preceding the ? is evaluated, if it’s true, then the expression preceding the : is executed, otherwise, the expression following : is executed.
How do I find out the number of parameters passed into function?
func_num_args() function returns the number of parameters passed in.
What’s the difference between accessing a class method via -> and via ::?
“::” is allowed to access methods that can perform static operations, i.e. those, which do not require object initialization.
What’s the special meaning of __sleep and __wakeup?
__sleep returns the array of all the variables than need to be saved, while __wakeup retrieves them.
Would you initialize your strings with single quotes or double quotes?
Since the data inside the single-quoted string is not parsed for variable substitution, it’s always a better idea speed-wise to initialize a string with single quotes, unless you specifically need variable substitution.