The define() directive lets us defining a constant as follows:
define ("ACONSTANT", 123);
How can you pass a variable by reference?
To be able to pass a variable by reference, we use an ampersand in front of it, as follows $var1 = &$var2
Will a comparison of an integer 12 and a string "13" work in PHP?
"13" and 12 can be compared in PHP since it casts everything to the integer type.
If the variable $var1 is set to 10 and the $var2 is set to the character var1, what's the value of $$var2?
$$var2 contains the value 10.
What does accessing a class via :: means?
:: is used to access static methods that do not require object initialization.
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| Convergys Most Frequently Asked Latest PHP Interview Questions Answers |
In PHP, objects are they passed by value or by reference?
In PHP, objects passed by value.
Are Parent constructors called implicitly inside a class constructor?
No, a parent constructor have to be called explicitly as follows:
parent::constructor($value)
What's the difference between __sleep and __wakeup?
__sleep returns the array of all the variables that need to be saved, while __wakeup retrieves them.
What is faster?
1- Combining two variables as follows:
$variable1 = 'Hello ';
$variable2 = 'World';
$variable3 = $variable1.$variable2;
Or
2- $variable3 = "$variable1$variable2";
$variable3 will contain "Hello World". The first code is faster than the second code especially for large large sets of data.
What does $_COOKIE mean?
$_COOKIE is an associative array of variables sent to the current PHP script using the HTTP Cookies.
What does the scope of variables mean?
The scope of a variable is the context within which it is defined. For the most part, all PHP variables only have a single scope. This single scope spans included and required files as well.
Is it possible to submit a form with a dedicated button?
It is possible to use the document.form.submit() function to submit the form. For example: <input type=button value="SUBMIT" onClick="document.form.submit()">
What is the difference between ereg_replace() and eregi_replace()?
The function eregi_replace() is identical to the function ereg_replace() except that it ignores case distinction when matching alphabetic characters.
Is it possible to protect special characters in a query string?
Yes, we use the urlencode() function to be able to protect special characters.
What are the three classes of errors that can occur in PHP?
The three basic classes of errors are notices (non-critical), warnings (serious errors) and fatal errors (critical errors).
What is the difference between characters \034 and \x34?
\034 is octal 34 and \x34 is hex 34.
How can we pass the variable through the navigation between the pages?
It is possible to pass the variables between the PHP pages using sessions, cookies or hidden form fields.
Is it possible to extend the execution time of a PHP script?
The use of the set_time_limit(int seconds) enables us to extend the execution time of a PHP script. The default limit is 30 seconds.
Is it possible to destroy a cookie?
Yes, it is possible by setting the cookie with a past expiration time.