Easy to integrate Facebook login to your web application

<fb:login-button scope="public_profile,email" onlogin="checkLoginState();">
</fb:login-button>
<span id="status"></span>
<script type='text/javascript'>
function statusChangeCallback(response) {
    console.log('statusChangeCallback');
    console.log(response);
    if (response.status === 'connected') {
      testAPI();
    } else if (response.status === 'not_authorized') {
      document.getElementById('status').innerHTML = 'Please log ' +'into this app.';
    } else {
      document.getElementById('status').innerHTML = 'Please log ' +'into Facebook.';
    }
}
function checkLoginState() {
    FB.getLoginStatus(function(response) {  statusChangeCallback(response); });
}

window.fbAsyncInit = function() {
    FB.init({
        appId      : "FB_APP_ID", 
        cookie     : true,  // enable cookies to allow the server to access // the session
        xfbml      : true,  // parse social plugins on this page
        version    : 'v2.1' // use version 2.1
    });
    //FB.getLoginStatus(function(response) {  statusChangeCallback(response); });
};

(function(d, s, id) {
    var js, fjs = d.getElementsByTagName(s)[0];
    if (d.getElementById(id)) return;
    js = d.createElement(s); js.id = id;
    js.src = "//connect.facebook.net/en_US/sdk.js";
    fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));

function testAPI() {
    console.log('Welcome!  Fetching your information.... ');
    FB.api('/me', function(response) {
        console.log('Successful login for: ' + response.name);
        var name = response.name;
        var email = response.email;
        document.getElementById('status').innerHTML = 'Thanks for logging in, ' + response.email + '!';
    });
}
</script>

How to connect to MySQL from the command line?

Connect to MySQL from the command line

To connect to MySQL from the command line:

    Log in to your A2 Hosting account using SSH.
    At the command line, type the following command, replacing USERNAME with your username:

    mysql -u USERNAME -p

    At the Enter Password prompt, type your password. When you type the correct password, 
the mysql> prompt appears.

    To display a list of databases, type the following command at the mysql> prompt:

    show databases;

    To access a specific database, type the following command at the mysql> prompt, 
replacing DBNAME with the database that you want to access:

    use DBNAME;

    After you access a database, you can run SQL queries, list tables, and so on. Additionally:
        To view a list of MySQL commands, type help at the mysql> prompt.
        To exit the mysql program, type \q at the mysql> prompt.

To modify the maximum number of input variables for PHP scripts in php.ini directives

To modify the maximum number of input variables for PHP scripts in php.ini directives
max_input_vars = 1500

To change the memory limit for PHP in php.ini directives

To change for this in php.ini
memory_limit = 256M

To set the PHP error log location in php.ini directives

PHP error log location in php.ini file
Enable:
error_log = /path/filename
Disable
;error_log = /path/filename

To change the PHP time zone setting in php.ini directives

To change the PHP time zone setting in php.ini file
date.timezone = "Europe/Paris"

To change the maximum upload file size for PHP in php.ini directives

In php.ini file change below this,
upload_max_filesize = 20M
post_max_size = 21M

To change execution time in php.ini directives

In php page change execution tin in php.ini file max_execution_time = 100;

Document onkeydown get keyCode in javascript

document.onkeydown = myKeyDownHandler;
function myKeyDownHandler(event){
      alert(event.keyCode)
}

how to find server space in php?

// $ds contains the total number of bytes available on "/"
$ds = disk_total_space("/");

// On Windows:
$ds = disk_total_space("C:");
$ds = disk_total_space("D:");

Hoe to find os by using php?

echo php_uname();
echo PHP_OS;
/* Some possible outputs:
Linux localhost 2.4.21-0.13mdk #1 Fri Mar 14 15:08:06 EST 2003 i686
Linux
FreeBSD localhost 3.2-RELEASE #15: Mon Dec 17 08:46:02 GMT 2001
FreeBSD
Windows NT XN1 5.1 build 2600
WINNT
*/
if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
    echo 'This is a server using Windows!';
} else {
    echo 'This is a server not using Windows!';
}

To Calculate distance between two latitude & longitude in php

Method I :

function distance($lat1, $lon1, $lat2, $lon2, $unit) {

  $theta = $lon1 - $lon2;
  $dist = sin(deg2rad($lat1))*sin(deg2rad($lat2))+
cos(deg2rad($lat1))*cos(deg2rad($lat2))*cos(deg2rad($theta));
  $dist = acos($dist);
  $dist = rad2deg($dist);
  $miles = $dist * 60 * 1.1515;
  $unit = strtoupper($unit);

  if ($unit == "K") {
    return ($miles * 1.609344);
  } else if ($unit == "N") {
      return ($miles * 0.8684);
    } else {
        return $miles;
      }
}

echo distance(11.01078,76.93433,11.14137,78.59412,10.1, "M") . " Miles
";
echo distance(11.01078,76.93433,11.14137,78.59412,10.1, "K") . " Kilometers
";
echo distance(11.01078,76.93433,11.14137,78.59412,10.1, "N") . " Nautical Miles
";

Method II:

function calculateDistance($latitude1, $longitude1, $latitude2, $longitude2) {
    $theta = $longitude1 - $longitude2;
    $miles = (sin(deg2rad($latitude1)) * sin(deg2rad($latitude2))) + 
(cos(deg2rad($latitude1)) * cos(deg2rad($latitude2)) * cos(deg2rad($theta)));
    $miles = acos($miles);
    $miles = rad2deg($miles);
    $miles = $miles * 60 * 1.1515;
    return $miles;
}

Resize image by using PHP GD functions

header('Content-Type: image/jpeg');
$w=100;
$h=100;
$filename = 'picture.jpg';
for($i=0;$i<10;$i++){
$rfname="images/re$i.jpg";
resize($filename,$w,$h,$rfname);
}
function resize($filename,$w,$h,$rfname){
list($width, $height) = getimagesize($filename);
$image_p = imagecreatetruecolor($w,$h);
$image = imagecreatefromjpeg($filename);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $w, $h, $width, $height);
imagejpeg($image_p,'', 100);
imagejpeg($image_p,$rfname);
}

How to read data from excel file using php?

<?php
include 'reader.php';
$excel = new Spreadsheet_Excel_Reader();
?>
<table  border="1">
<?php
$excel->read('sample.xls');//set the excel file name here   
$x=1;
while($x<=$excel->sheets[0]['numRows']) { // reading row by row 
echo "\t<tr>\n";
$y=1;
while($y<=$excel->sheets[0]['numCols']) {// reading column by column 
$cell = isset($excel->sheets[0]['cells'][$x][$y])?$excel->sheets[0]['cells'][$x][$y] :'';
if($cell)
echo "\t\t<td>$cell</td>\n";  // get each cells values
$y++;
}  
echo "\t</tr>\n";
$x++;
}
?>    
</table><br/>

Clock running scripts in php with jquery

<div class="col-xs-12 col-sm-12 col-lg-12 cal">
      <p id='demo' class="text-center cal-container"></p> 
   </div>
                       </a>
                       <?php
   
   $current_timestamp = time();
  ?>
                       <script type='text/javascript'>
                        flag = true;
            timer = '';
            phpJavascriptClock();
            setInterval(function(){phpJavascriptClock();},1000);
 
            function phpJavascriptClock()
            {
               
                if ( flag ) {
                    timer = <?php echo $current_timestamp;?>*1000;
                }
                var d = new Date(timer);
                months = new Array('Jan', 'Feb', 'Mar', 'Apr', 'May', 
'Jun', 'Jul', 'Aug', 'Sept', 'Oct', 'Nov', 'Dec');
 
                month_array = new Array('January', 'Febuary', 'March', 
'April', 'May', 'June', 'July', 'Augest', 'September', 'October', 
'November', 'December');
 
                currentYear = d.getFullYear();
                month = d.getMonth();
                var currentMonth = months[month];
                var currentMonth1 = month_array[month];
                var currentDate = d.getDate();
                currentDate = currentDate < 10 ? '0'+currentDate : currentDate;
 
                var hours = d.getHours();
                var minutes = d.getMinutes();
                var seconds = d.getSeconds();
 
                var ampm = hours >= 12 ? 'PM' : 'AM';
                hours = hours % 12;
                hours = hours ? hours : 12; // the hour ’0' should be ’12'
                minutes = minutes < 10 ? '0'+minutes : minutes;
                seconds = seconds < 10 ? '0'+seconds : seconds;
                var strTime = hours + ':' + minutes+ ':' + seconds + ' ' + ampm;
                document.getElementById("demo").innerHTML= currentMonth+' 
' + currentDate+' , ' + currentYear + ' ' + strTime ;
                flag = false;
                timer = timer + 1000;
            }
                       </script>

Json PHP encode value decode in jquery

var objJSON = eval("(function(){return " + resp + ";})()"); // resp is ajax reponse in json encoded by php "objJSON .name" to take values

How to take dates between two dates in php?

   $task_to_do = array();
   echo "
";
   $s = strtotime("START_DATE");
   $d = strtotime("END_DATE");
   $dif = 86400;
   $i=$s;
   $x=0;
   while ($i <= $d) {
      $dat = date("Y-m-d 00:00:00",$i);
      $t_s = date("Y-m-d 00:00:00",strtotime($dat));
      $t_e = date("Y-m-d 23:59:59",strtotime($dat));
      $task_to_do[$x]["start_date"] = $t_s;
      $task_to_do[$x]["end_date"] = $t_e;
      $i = $i+$dif;
      $x++;
   }
   echo "
";
   print_r($task_to_do);

Disable Hotlinking Images from Searchengines with htaccess

The following code is used to prevent HotLinking to jpg, jpeg, gif, png, and bmp file types.

RewriteEngine on
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://(www.)?your-websitename.com/.*$ [NC]
RewriteRule .(jpg|jpeg|gif|png|bmp)$ - [F]

To add watermark image with original image by using php GD functions

$main_img = "Porsche_911_996_Carrera_4S.jpg"; // main big photo / picture
$watermark_img = "watermark.gif"; // use GIF or PNG, JPEG has no tranparency support
$padding = 80; // distance to border in pixels for watermark image
$opacity = 20; // image opacity for transparent watermark
$watermark = imagecreatefromgif($watermark_img); // create watermark
$image = imagecreatefromjpeg($main_img); // create main graphic
if(!$image || !$watermark) die("Error: main image or watermark could not be loaded!");
$watermark_size = getimagesize($watermark_img);
$watermark_width = $watermark_size[0];
$watermark_height = $watermark_size[1];
$image_size = getimagesize($main_img);
$dest_x = $image_size[0] - $watermark_width - $padding+10;
$dest_y = $image_size[1] - $watermark_height - $padding-80;
// copy watermark on main image
imagecopymerge
($image, $watermark,$dest_x, $dest_y, 0, 0, 
$watermark_width, $watermark_height, $opacity);
// print image to screen
header("content-type: image/jpeg");
imagejpeg($image);
imagedestroy($image);
imagedestroy($watermark); 

To Crop image using PHP GD function

cropImage(150,100, 'example.png', 'png', 'image.png');
function cropImage($nw, $nh, $source, $stype, $dest) {
$size = getimagesize($source);
echo "
".$w = 500;
echo "
".$h = 400;
switch($stype) {
case 'gif':
$simg = imagecreatefromgif($source);
break;
case 'jpg':
$simg = imagecreatefromjpeg($source);
break;
case 'png':
$simg = imagecreatefrompng($source);
break;
}
$dimg = imagecreatetruecolor($nw, $nh);
echo "
".$wm = $w/$nw;
echo "
".$hm = $h/$nh;
echo "
".$h_height = $nh/2;
echo "
".$w_height = $nw/2;
if($w> $h) {
echo "
".$adjusted_width = $w / $hm;
echo "
".$half_width = ($adjusted_width / 2)+25;
echo "
".$int_width = $half_width - $w_height;
imagecopyresampled($dimg,$simg,-$int_width,0,0,0,$adjusted_width,$nh,$w,$h);
}
elseif(($w <$h) || ($w == $h)) {
$adjusted_height = $h / $wm;
$half_height = $adjusted_height / 2;
$int_height = $half_height - $h_height;
imagecopyresampled($dimg,$simg,0,-$int_height,0,0,$nw,$adjusted_height,$w,$h);
} else {
imagecopyresampled($dimg,$simg,0,0,0,0,$nw,$nh,$w,$h);
}

imagejpeg($dimg,$dest,100);
}