Search and replace in php

<?php
$offset = 0;

if(isset($_POST['text']) && isset($_POST['search']) && isset($_POST['replace'])){
 $text = $_POST['text'];
 $search = $_POST['search'];
 $replace = $_POST['replace'];

 $search_length = strlen($search);
 
 if(!empty($text) && !empty($search) && !empty($replace)){
   while($strpos = strpos($text, $search, $offset)){
   $offset = $strpos + $search_length;
   $text = substr_replace($text, $replace, $strpos, $search_length);
   echo $text;
   }
 }else{
   echo 'Please fill all fields!';
 }
}
?>

<hr />
<form action="searchandreplace.php" method="POST">
<textarea name="text" rows="15" cols="60"></textarea><br /><br />
Search : </br>
<input type="text" name="search"><br /><br />
Replace : </br>
<input type="text" name="replace"><br /><br />
<input type="submit" value="Submit">
</form>

Wordcensoring in php

From the following example, you can learn the usage of form, textarea, isset, strtolower and str_replace. Every word 'love' you type in the text box, the codes will change with the word 'hate'.

<?php
$find = 'love';
$replace = 'hate';
if(isset($_POST['user_input']) && !empty($_POST['user_input'])){
   $user_input = strtolower($_POST['user_input']);
   $user_input_new = str_replace($find, $replace, $user_input);
   echo $user_input_new.'</br>';
}else{
  echo 'Please fill in the text box!';
}
?>

<form action = "wordcensoring.php" method = "POST">
<textarea name = "user_input" cols = "40" widths = "500"></textarea></br></br>
<input type = "submit" value = "Submit">
</form>

Array in php

 Normally There are three types of array: Indexed Array, Associative Array and Multi-Dimentional Array.

1. Indexed Array (Works with number)

<?php
$snack = array('Banana', 'Ice-cream', 'Coconet', 'Mango', 'Orange');
$snack[1]='Alcohol';
echo $snack[1];
//print_r($snack);
?>
 

 2. Associative Array (Works with name)

<?php
$snack = array('Banana' => 100, 'Apple' => 200, 'Cake' => 300);
echo 'The cake is '.$snack['Cake']. ' Kyat.';
?>


3. Multi-Dimentional Array

<?php
$food = array('Healthy'=>array('Salad'=>200, 'Milk'=>100, 'Coconet'=>200),
              'Unhealthy'=>array('Alcohol'=>200, 'Beer'=>300));

foreach($food as $element => $inner_array){
  echo '<br /><strong>'.$element.'</strong><br />';
  foreach($inner_array as $inner_element => $item){
    echo $inner_element.' = '.$item.'<br />';
  }
}
?>

Using html form in php

<?php
 if(isset($_POST["username"]) && isset($_POST["password"])){
  $username = $_POST["username"];
  $password = $_POST["password"];

  if(!empty($username) && !empty($password)){
   echo 'Welcome to TNW, '.$username.'!';
  }else{
   echo 'Fill in all fields!';
  }
 }
?>

<form action = "test.php" method = "POST">
 Username:<br />
 <input type = "text" name = "username"><br /><br />
 Password:<br />
 <input type = "password" name = "password"><br /><br />
 <input type = "submit" value = "Log In">
</form>