Interview Questions on PHP
41. How to get a character in particular position of string in php?
Syntax :- $string_name(index_number);
Ex :-
$string = 'abcdef';
echo $string[0]; // a
echo $string[3]; // d
42. How to get index of character/substring of string in php?
Ex :- strops(“main string”,”sub string”);
<?php
echo strpos("I love php, I love php too!","php");
?>
43. How to connect to a database?
// Create connection
$conn = new mysqli($servername, $username, $password);
44. How to execute mysql commands in php?
$sql= “write sql command here ”;
$conn->query($sql);
45. How to assign default values for argument?
Using get :
GET requests can be cached
GET requests remain in the browser history
46. What is the difference b/w get and post?
Using get :
GET requests can be cached
GET requests remain in the browser history
Using post :
POST requests are never cached
POST requests do not remain in the browser history
47. How to access form input values in php?
Use $_POST or $_GET
Ex :- $_POST[‘form_input_name’];
48. How to know total number of elements in array?
Use count();
Ex :-
<?php
$a[0] = 1;
$a[1] = 3;
$a[2] = 5;
$result = count($a);
// $result == 3
?>
49. How to encrypt to md5 in php?
Use md5 function
Ex :-
<?php
$str = 'apple';
if (md5($str) === '1f3870be274f6c49b3e31a0c6728957f') {
echo "Would you like a green or red apple?";
}
?>
50. How to upload file in php?
Syntax :- move_uploaded_file ( string $filename , string $destination );
Ex :-
<?php
$uploads_dir = '/uploads';
$tmp_name = $_FILES["fileToUpload"]["tmp_name"];
move_uploaded_file($tmp_name, "$uploads_dir/filename ");
?>