How to implement a function that writes an array in php

PHP is a widely used scripting language that is widely used in web development. Array is a very important data type in PHP. It can store a set of values ​​and allows you to find, add or delete elements based on key values. Arrays in PHP are very flexible and can be easily modified and manipulated. In PHP, you can put multiple arrays in a function and use these arrays by calling the function to improve code reusability and readability. Next, we will introduce in detail how to write an array as a function.

Write a function

Arrays are a very common data type in PHP. You can use arrays to store multiple values ​​and operate on these values. In PHP, you can customize an array type function, define a parameter inside the function that can store multiple values, and operate on this parameter. Simply put, you can encapsulate an array containing multiple key-value pairs into a function, and call this function to get the required value in the array.

Implementing a function that writes an array

In PHP, one of the ways to reuse code is to define a function. So how to define a function that can output an array? Let's look at an example below:

function outputArray($array) {
    echo "<pre class="brush:php;toolbar:false">";
    print_r($array);
    echo "

"; }

This function is called "outputArray", takes a parameter $array, and outputs a formatted array.

$array = [
    "name" => "Tom",
    "age" => 18,
    "city" => "Shanghai"
];

outputArray($array);

Above we defined a simple array containing name, age and city. Next we call the outputArray function and pass the array to this function. Through this function, we can format and output the contents of this array.

Implement a function that reads an array

In addition to outputting an array, we can also perform various operations on the key-value pairs of the array. For example, we can design a simple function to map a given key name to the corresponding value in the array:

function getValue($array, $key) {
    return $array[$key];
}

Next, we use this function to get the key value in the array:

$array = [
    "name" => "Tom",
    "age" => 18,
    "city" => "Shanghai"
];

echo getValue($array, "name");

In the above code, we passed the parameters $array and $key to the function getValue, and returned the value Tom corresponding to the name in the array.

Implementing a function for writing and reading arrays

We can also encapsulate writing and reading arrays in the same function. This function can have two parameters, one is an array and the other is a string. Once a string is passed in, the function will return the array value corresponding to the string.

function getSetArrayValue($array, $key = "") {
    if($key != "") {
        return $array[$key];
    } else {
        $array["name"] = "Mark";
        $array["email"] = "mark@example.com";
        return $array;
    }
}

In the above code, the getSetArrayValue function writes some new key-value pairs in the array when the second parameter key is empty, and then returns the entire array. When key is not empty, the function only returns the value corresponding to the key.

$array = [];

// Sets default values for array, returns the whole array
$array = getSetArrayValue($array);
outputArray($array);

// Gets individual array value from key "name"
$singleValue = getSetArrayValue($array, "name");
echo $singleValue;

Run the above code and you will get the output of the entire array, as well as the value of the name key individually. This function can simplify the code and increase readability.

Summary

In this article, we introduced how to use functions to work with arrays in PHP. Array is a very common data type in PHP, which can be used to store multiple values ​​and perform various operations. By encapsulating arrays into functions, the readability and reusability of the code can be greatly improved. In practice, you can use these methods to design your own functions, process array data in actual development, optimize the code and speed up the development process.

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