How to jump to page and extract array in php

PHP is a very popular and commonly used scripting language. It is widely used in Web development, especially for server-side website development. In website development, sometimes it is necessary to jump to a page, and the data in the array needs to be extracted after the jump. So, this article will give you a detailed introduction to how to implement page jumps and extract arrays in PHP.

1. How to jump to a page in PHP

In PHP, jumping to a page is usually implemented through redirection. PHP provides two methods to implement redirection: header() and location().

header() method: The

header() method can send HTTP header information to the client browser, including the address of the jump page. When the browser receives the HTTP header information sent by the header() method, it will jump according to the address specified by the header information. The following is an example of using the header() method to implement jump:

<?php
header("Location: http://www.example.com/");
exit;
?>

In this example, the first parameter of the header() method is the address of the jump page, and the second parameter is optional. Used to control HTTP status codes. The exit statement is used to abort a PHP script to ensure that nothing else is output and thus avoids causing PHP warnings or errors.

location() method:

The location() method is a method in the PHP built-in class library. Its function is similar to the header() method, but it is simpler to use. The following is an example of using the location() method to implement a jump:

<?php
$url = "http://www.example.com/";
echo "<script language='javascript' type='text/javascript'>";
echo "window.location.href='$url'";
echo "</script>";
?>

In this example, the echo statement is used to output a piece of JavaScript code, which is used to redirect the browser to the specified address. It should be noted that the location() method can only successfully jump without outputting anything.

2. Methods for extracting arrays in PHP

In PHP, extracting array data is usually achieved through array subscripts. The following will introduce three commonly used methods for extracting array data.

1. Traverse the array

Traversing the array is the most commonly used method to extract data. You can use a for loop or foreach loop to traverse the array, as shown below:

<?php
$arr = array('apple', 'banana', 'orange');
for($i = 0; $i < count($arr); $i++) {
    echo $arr[$i].' ';
}
echo '<br>';
foreach($arr as $value) {
    echo $value.' ';
}
?>

In this example, an array $arr is first created, and then a for loop and a foreach loop are used to traverse the array and output the array elements. It should be noted that when using a for loop to traverse an array, you need to use the count() function to obtain the array length.

2. Use array functions

PHP provides a series of array functions, such as array_keys(), array_values(), array_flip(), etc. These functions can help us extract arrays more conveniently data. The following are some commonly used array function examples:

<?php
$arr = array('name' => 'Tom', 'age' => 18, 'gender' => 'male');
$keys = array_keys($arr);
$values = array_values($arr);
$flipArr = array_flip($arr);
echo 'Keys: '.implode(', ', $keys).'<br>';
echo 'Values: '.implode(', ', $values).'<br>';
print_r($flipArr);
?>

In this example, an associative array $arr is first created, and then the array_keys() function is used to obtain the array key name, the array_values() function is used to obtain the array element value, array_flip () function swaps the array key names and element values, and finally uses the implode() function to output the result.

3. Use the json_decode() function

If the array element is a string in JSON format, you can use the json_decode() function to decode it into a PHP array, and then extract the data, as follows Shown:

<?php
$jsonStr = '{"name":"Tom", "age":18, "gender":"male"}';
$arr = json_decode($jsonStr, true);
echo 'Name: '.$arr['name'].'<br>';
echo 'Age: '.$arr['age'].'<br>';
echo 'Gender: '.$arr['gender'].'<br>';
?>

In this example, a JSON format string $jsonStr is first created, then the json_decode() function is used to decode it into a PHP array, and finally the array elements are output.

Summary:

In PHP, jumping pages and extracting array data are very common operations. This article introduces three methods of jumping pages and extracting array data in PHP, and Corresponding code examples are given. If you are developing a PHP website, you can refer to the sample code in this article to implement page jumps and extract array data to improve development efficiency.

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