Web Technology Experts Notes

Thursday, 19 November 2015

Top 10 jQuery interview Questions and Answers

Question: How to replace the text of div using class?
Suppose HTML

<div class="myDivClass">
Update this text</div>

jQuery code

$('.myDivClass').text('Updated');

Question: How to replace the text of div using "div id"?
Suppose HTML

<div id="myDivId">
Update this text</div>

jQuery code

$('#myDivId').text('Updated');

Question: How to replace the html of div using class?
Suppose HTML

<div class="myDivClass">
Update this html</div>

jQuery code

$('.myDivClass').html('Updated');

Question: How to replace the text of div using "div id"?
Suppose HTML

<div id="myDivId">
Update this text</div>

jQuery code

$('#myDivId').html('Updated');

Question: How to Check if checkbox is checked?
Suppose HTML is

<input name="lang[]" type="checkbox" value="English" />
<input name="lang[]" type="checkbox" value="Hindi" />
<input name="lang[]" type="checkbox" value="Urdu" />

JQuery code

var totalCheckboxSelected = $('input[name="lang[]"]:checked').length;
if(totalCheckboxSelected){
    console.log(totalCheckboxSelected+' check box checked');
}else{
    console.log('NO checkbox is selected');
}

Question: How can you check for a #hash in a URL?

if(window.location.hash) {
    var hashValue = window.location.hash.substring(1);
    console.log(hashValue);
} else {
  console.log('Hash not found');
}

Question: How get to know which mouse button is pressed?

$('#divId').mousedown(function(event) {
    switch (event.which) {
        case 1:
            console.log('Left button pressed.');
            break;
        case 2:
            console.log('Middle button pressed.');
            break;
        case 3:
            console.log('Right button pressed.');
            break;
        default:
            console.log('Exception Case!');
    }
});

Question: How to add update the color of div with jQuery?

$('div#divId').css("background-color", "red");

Question: How to remove class from div?

$("div#divId").removeClass('className');

Question: How do I get the value of a textbox using jQuery?
Html

<input id="websiteId" name="website" type="text" value="Web Technology Experts Notes" /> jQuery:

$("#websiteId").val();

Question: How to submit form with post method with Ajax?
HTML Form

<form action="/ajax/form-url" id="ajaxform" method="POST" name="ajaxform">
First Name: <input name="fname" type="text" value="" /> <br />
Last Name: <input name="lname" type="text" value="" /> <br />
<input name="submit" type="submit" value="Submit the Form" /> </form>

jQuery Code

$( document ).ready(function() {
    $("#ajaxformSubmit").submit(function(e)
    {
        var postData = $(this).serializeArray();
        var formURL = '/ajax/form-url'
        $.ajax(
        {
            url : formURL,
            type: "POST",
            data : postData,
            success:function(data, textStatus) 
            {            console.log(data);
            }
        });
        e.preventDefault(); //STOP default action
    });
});

Question: How to escape the text?

var someHtmlString = "";
var escaped = $("
").text(someHtmlString).html();
console.log(escaped); //<script>aalert('hi!');</script>

Sunday, 15 November 2015

Top 10 PHP Interview Questions and Answers

Question 1: How to redirect a page to another?
You can use header function to recirect.

header('location: http://www.web-technology-experts-notes.in"); //Redirect to home page of another website

header('location: http://www.web-technology-experts-notes.in/2015/11/php-questions-and-answers-for-experienced.html"); //Redirect to another page and another website

header('location: php-questions-and-answers-for-experienced.html"); //Redirect to another page of same website

header('location: php-questions-and-answers-for-experienced.html?topic=php");  //Redirect to another page of same website with parameter

header('Location: http://www.web-technology-experts-notes.in/2015/11/php-questions-and-answers-for-experienced.html', true, 301); //Permanent Redirect

Following are different use of header functions.

Redirect from one page to another page. Also can redirect to another website.
Help to download the file like (csv download, pdf download etc).
Browser Authentication to the web page.
Set the header of any page at the top of page.

Question 2: Is it secure to store a password in a session?
No,
If you still need then please stored in encrypted form with different name (not password).

Question 3: How to set/get PHP array in cookie?

//Set an array in cookie
$arrayData=json_encode(array(1,2,3,4,5,6));
setcookie('no_array', $arrayData);

//Get an array from cookie
$cookie = $_COOKIE['no_array'];
$arrayData = json_decode($cookie);
print_r($arrayData);

Question 4: What is the difference between bindParam and bindValue?

$string='this is ';
if (strlen($string) != strlen(utf8_decode($string)))
{
    echo 'is unicode';
}else{
  echo 'It is Not unicode.';
}

Question 5: How to add 30 mins to a date?

$date = date("Y-m-d H:i:s");
date("Y/m/d h:i:s", strtotime("+30 minutes", $date));

Question 6: How to get Path From URL?

$url = "http://www.web-technology-experts-notes.in/2013/09/amazon-s3-introduction.html";
$path = parse_url($url);
print_r($path);
/**Array
(
    [scheme] => http
    [host] => www.web-technology-experts-notes.in
    [path] => /2013/09/amazon-s3-introduction.html
)*/

Question 7: How to get array elements which present in two different array?

$array1 = array("a" => "green", "red", "blue");
$array2 = array("b" => "green", "yellow", "red");
$result = array_intersect($array1, $array2);
print_r($result);
/**Array ( [a] => green [0] => red )*/

Question 8: How to replace array elements with another another?

$input = array("red", "green", "blue", "yellow");
array_splice($input, -1, 1, array("black", "maroon"));
print_r($input);

/*Array ( [0] => red [1] => green [2] => blue [3] => black [4] => maroon )*/

Question 9: Count number of elements in an array?

$foodArray = array('fruits' => array('orange', 'banana', 'apple'),
              'veggie' => array('carrot', 'collard', 'pea'));

echo count($foodArray); // output 2
// recursive count
echo count($foodArray, COUNT_RECURSIVE); // output 8

Question 10: How to exchanges all keys with their associated values in an array?

$input = array("oranges", "apples","mango", "pears");
$flippedArray = array_flip($input);

print_r($flippedArray);
/*Array ( [oranges] => 0 [apples] => 1 [mango] => 2 [pears] => 3 )*/