How to display array in php

In PHP programming, arrays are a very commonly used data type, especially in web development. When we use an array to store a set of data, how do we display the contents of the array? This article will introduce several array display methods commonly used in PHP.

1. Use the print_r() function

In PHP, you can use the print_r() function to output the contents of the array. This function can not only output simple arrays, but also output data structures of any complexity, such as objects and multi-dimensional arrays.

Sample code:

$fruits = array('apple', 'banana', 'orange');
print_r($fruits);

Output result:

Array
(
    [0] => apple
    [1] => banana
    [2] => orange
)

As can be seen from the results, the print_r() function will output the keys and values ​​​​of the array together, so that we can Visually view the array contents.

Note: The print_r() function is only for debugging and should not be used for final page output. Using the print_r() function multiple times will increase the loading time of the page and reduce the user experience.

2. Use the var_dump() function

In addition to the print_r() function, PHP also provides another function var_dump() for outputting an array. Different from the print_r() function, the var_dump() function not only outputs the contents of the array, but also outputs information such as keys, values, and data types, which helps to understand the data structure more comprehensively.

Sample code:

$fruits = array('apple', 'banana', 'orange');
var_dump($fruits);

Output result:

array(3) {
  [0]=>
  string(5) "apple"
  [1]=>
  string(6) "banana"
  [2]=>
  string(6) "orange"
}

It can be seen that the output of the var_dump() function is more detailed and accurate than the print_r() function, but at the same time Increase the length of page output.

3. Use foreach loop

In addition to the above two functions, we can also use foreach loop to traverse the array, and then output the key and value of each element in the loop. This method is more flexible and you can output the array contents according to your own needs.

Sample code:

$fruits = array('apple', 'banana', 'orange');
foreach ($fruits as $key => $value) {
    echo "键：" . $key . ", 值：" . $value . "<br>";
}

Output result:

键：0, 值：apple
键：1, 值：banana
键：2, 值：orange

It can be seen that by using the foreach loop to traverse the array, we can output the array content according to our own needs.

Summary:

In PHP programming, array is a very commonly used data type. In order to facilitate developers to view the contents of arrays, PHP provides a variety of ways to display arrays, the most commonly used methods include print_r(), var_dump() functions and foreach loops. We can choose the appropriate method according to actual needs.

The above is the detailed content of How to display array in php. For more information, please follow other related articles on the PHP Chinese website!