Php Interview Questions and Answers for Experienced

7/28/2019 Php Interview Questions and Answers for Experienced

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php interview questions and answers forexperienced1:What is the value of $b in the following code?

$a="5 USD";

$b=10+$a;echo $b;

?>

Ans:152:What are the differences between Get and post methods in form submitting, give the casewhere we can use get and we can use post methods? In the get method the data made available to the action page ( where data is received ) by the URL

so data can be seen in the address bar. Not advisable if you are sending login info like passwordetc.

In the post method the data will be available as data blocks and not as query string. 3:What is GPC? G

–Get

P – PostC – Cookies4:What are super global arrays?

All variables that come into PHP arrive inside one of several special arrays known collectively as thesuperglobals. They're called superglobal because they are available everywhere in your script,even inside classes and functions.5:Give some example for super global arrays? $GLOBALS$_GET$_POST$_SESSION

$_COOKIE$_REQUEST$_ENV$_SERVER6:What's the difference between COPY OF A FILE & MOVE_UPLOAD_FILE in file uploading?

MOVE_UPLOAD_FILE : This function checks to ensure that the file designated by filename is avalid upload file (meaning that it was uploaded via PHP's HTTP POST upload mechanism). If the fileis valid, it will be moved to the filename given by destination.If filename is not a valid upload file, then no action will occur, and move_uploaded_file() will returnFALSE.Copy :Makes a copy of a file. Returns TRUE if the copy succeeded, FALSE otherwise.7:When I do the following, the output is printed in the wrong order:

function myfunc($argument) {echo $argument + 10;

}$variable = 10;

echo "myfunc($variable) = " . myfunc($variable);

What's going on?



To be able to use the results of your function in an expression (such as concatenating it with other strings in the example above), you need to return thevalue, not echo it.8:What are the Formatting and Printing Strings available in PHP?

Function Description

printf() : Displays a formatted stringsprintf() : Saves a formatted string in a variablefprintf() : Prints a formatted string to a filenumber_format() : Formats numbers as strings9:Explain the types of string comparision function in PHP.

Function Descriptionsstrcmp() :Compares two strings (case sensitive)strcasecmp() :Compares two strings (not case sensitive)strnatcmp(str1, str2) :Compares two strings in ASCII order, but

any numbers are compared numericallystrnatcasecmp(str1, str2):Compares two strings in ASCII order,

case insensitive, numbers as numbers

strncasecomp() : Compares two strings (not case sensitive)and allows you to specify how many charactersto compare

strspn() : Compares a string against characters representedby a mask

strcspn() : Compares a string that contains characters not inthe mask

10:Explain soundex() and metaphone(). soundex()

The soundex() function calculates the soundex key of a string. A soundex key is a four character long alphanumeric string that represent English pronunciation of a word. he soundex() function canbe used for spelling applications.$str = "hello";echo soundex($str);?>metaphone() The metaphone() function calculates the metaphone key of a string. A metaphone key representshow a string sounds if said by an English speaking person. The metaphone() function can be usedfor spelling applications.echo metaphone("world");?>11:What do you mean range()?

Starting from a low value and going to a high value, the range() function creates an array of consecutive integer or character values. It takes up to three arguments: a starting value, an endingvalue, and an increment value. If only two arguments are given, the increment value defaults to 1.

Example :echo range(1,10); // Returns 1,2,3,4,5,6,7,8,9,10?>12:How to read and display a HTML source from the website url?

$filename="http://www.kaptivate.in/";$fh=fopen("$filename", "r");while( !feof($fh) ){$contents=htmlspecialchars(fgets($fh, 1024));print "



$contents

";}fclose($fh);?>13:What is properties of class? Class member variables are called "properties". We may also see them referred to using other terms

such as "attributes" or "fields", but for the purposes of this reference we will use "properties". Theyare defined by using one of the keywords public, protected, or private, followed by a normal variabledeclaration. This declaration may include an initialization, but this initialization must be a constantvalue that is, it must be able to be evaluated at compile time and must not depend on run-timeinformation in order to be evaluated.14:How to use HTTP Headers inside PHP? Write the statement through which it can beadded?

HTTP headers can be used in PHP by redirection which is written as:The headers can be added to HTTP response in PHP using the header(). The response headers aresent before any actual response being sent. The HTTP headers have to be sent before taking theoutput of any data. The statement above gets included at the top of the script.15:Why we used PHP? Because of several main reason we have to use PHP. These are:

1.PHP runs on many different platforms like that Unix,Linux and Windows etc.2.It codes and software are free and easy to download.3.It is secure because user can only aware about output doesn't know how that comes.4.It is fast,flexible and reliable.5.It supports many servers like: Apache,IIS etc.16:Arrays in PHP? Create array in PHP to solved out the problem of writing same variable name many time.In this wecreate a array of variable name and enter the similar variables in terms of element.Each element inarray has a unique key.Using that key we can easily access the wanted element.Arrays are essentialfor storing, managing and operating on sets of variables effectively. Array are of three types:1.Numeric array2.Associative array3.Multidimensional arrayNumeric array is used to create an array with a unique key.Associative array is used to create anarray where each unique key is associated with their value.Multidimensional array is used when wedeclare multiple arrays in an array.17:What is foreach loop in php? foreach:Uses, When When we want execute a block of code for each element in an array.Syntax:foreach (array as value){

code will be executed;}eg:$arr=array("one", "two", "three");

foreach ($arr as $value){echo "Value: " . $value . "

";} ?>18:How we used $_get and $_post variable in PHP?

We know that when we use $_GET variable all data_values are display on our URL.So,using thiswe don't have to send secret data (Like:password, account code).But using we can bookmarked the



importpage.We use $_POST variable when we want to send data_values without display on URL.And their isno limit to send particular amount of character.Using this we can not bookmarked the page.19:Why we use $_REQUEST variable? We use $_REQUEST variable in PHP to collect the data_values from $_GET,$_POST and

$_COOKIE variable.Example:R4R Welcomes You .

You are years old!20:How we handle errors in PHP?Explain it? In PHP we can handle errors easily.Because when error comes it gives error line with their respective line and send error message to the web browser.When we creating any web application and scripts. We should handle errors wisely.Because whenthis not handle properly it can make bg hole in security.In PHP we handle errors by using these methods:1.Simple "die()" statements2.Custom errors and error triggers

3.Error reporting21: How we use Custom errors and error triggers error handling method in PHP? In Custom errors and error triggers,we handle errors byusing self made functions.1.Custom error s : By using this can handle the multipleerrors that gives multiple message.Syntax:set_error_handler(\\\"Custom_Error\\\");In this syntax if we want that our error handle, handleonly one error than we write only one argument otherwisefor handle multiple errors we can write multiple arguments.

Example://function made to handle errorfunctioncustom_Error($errorno, $errorstr){

echo \\\"Error: [$errorno] $errorstr\\\"; }//set error handler like thatset_error_handler(\\\"custom_Error\\\");//trigger to that error echo($verify);?>

2.error trigger : In PHP we use error trigger to handlethose kind of error when user enter some input data.If data has an error than handle by error trigger function.

Syntax:

$i=0;if ($i<=1){trigger_error(\\\"I should be greater than 1 \\\");}?>In this trigger_error function generate error when i isless than or greater than 1.



22:What do you understand about Exception Handling in PHP? In PHP 5 we introduce a Exception handle to handle run time exception.It is used to change thenormal flow of the code execution if a specified error condition occurs.

An exception can be thrown, and caught("catched") within PHP. Write code in try block,Each trymust have at least one catch block. Multiple catch blocks can be used to catch different classes of exceptions.

Some error handler methods given below:1.Basic use of Exceptions2.Creating a custom exception handler 3.Multiple exceptions4.Re-throwing an exception5.Setting a top level exception handler 23: What is the difference b/n 'action' and 'target' in form tag? Action:

Action attribute specifies where to send the form-data whena form is submitted.

Syntax:Example:

action="formValidation.php">

Target: The target attribute specifies where to open the action URL.Syntax:

Value: _blank – open in new window

_self- Open in the same frame as it was clicked _parent- Open in the parent frameset _top- Open in the full body of the windowFramename- Open in a named frame24:What do you understand about PHP accelerator ?

Basically PHP accelerator is used to boost up the performance of PHP programing language.Weuse PHP accelerator to reduce the server load and also use to enhance the performance of PHPcode near about 2-10 times.In one word we can say that PHP accelertator is code optimizationtechnique.26:How we use ceil() and floor() function in PHP? ceil() is use to find nearest maximum values of passing value.Example:$var=6.5;$ans_var=ceil($var);echo $ans_var;Output:7floor() is use to find nearest minimum values of passing value.Example:$var=6.5$ans_var=floor($var);

echo $ans_var;Output:627:What is the answer of following code echo 1< 2 and echo 1 >2 ?

Output of the given code are given below:echo 1<2output: 1



echo 1>2output: no output28: What is the difference b/w isset and empty?The main difference b/w isset and empty are given below:isset: This variable is used to handle functions and checked a variable is set even through it isempty.

empty: This variable is used to handle functions and checked either variable has a value or it is anempty string,zero0 or not set at all.

Php Interview Questions and Answers for Experienced

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