How to see array in php

In PHP, array is a very important data type. Developers often need to use arrays to store and manipulate data. When we need to view the contents of an array, there are many ways to do it.

Method 1: Use the var_dump() function

Use the var_dump() function to print out all elements of the array. This function can not only output arrays, but also all variable types, including strings, integers, Boolean values, objects, etc. The following is a simple example:

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

The running results are as follows:

array(4) {
  [0]=>
  string(5) "apple"
  [1]=>
  string(6) "banana"
  [2]=>
  string(6) "orange"
  [3]=>
  string(5) "grape"
}

From this output, we can see that this array has four elements, each element is a string type .

Method 2: Use the print_r() function

The print_r() function can print out all elements of the array and display it in a more friendly format. The following is a simple example:

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

The running results are as follows:

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

It can be seen that the array output using the print_r() function is roughly the same as the array output using the var_dump() function, except The format is just different.

Method 3: Using foreach loop

Using foreach loop to traverse the array is a frequently used method. We can use foreach loop to output all elements in the array. The following is a simple example:

$arr = array('apple', 'banana', 'orange', 'grape');
foreach ($arr as $value) {
    echo $value . "
";
}

The running results are as follows:

apple
banana
orange
grape

As you can see, this method outputs each element value of the array, and each element value is displayed in one line. .

Summary:

In PHP, array is a very important data type. You can easily view the element values ​​of an array using the above three methods. Although these methods can all output array contents, they each have their own advantages and disadvantages, and developers need to choose the appropriate method according to their own needs.

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