Use str_split to quickly build string crosswords

M66 2025-05-18

In PHP, string manipulation is a very common requirement. If you are making a crossword game, or need to split a long string into several small segments, PHP's str_split function can help you quickly implement it. Today, we will introduce how to use this function and make a simple crossword game with a practical example.

What is the str_split function?

str_split is a built-in string function in PHP. Its function is to split a string into multiple small strings according to the specified length. The syntax of this function is as follows:

 str_split(string $string, int $length = 1): array

$string : The string you need to split.
$length : The length of each small string, default to 1.

If the $length parameter is not specified, str_split will break each character into a segment by default, that is, split the string into a single character array.

Example: Create a simple crossword game with str_split

Suppose we want to split a string by a certain length and make a simple crossword game. We will use str_split to split a long string into chunks and then assign these chunks to spaces in the game.

Step 1: Prepare a long string

First, prepare a string that will be the answer to our crossword game.

 $answer = "PHPPROGRAMMING";

Step 2: Splitting the string with str_split

Next, we use str_split to split this string into several small segments according to a fixed length. For example, we take every 4 characters as a group.

 $chunks = str_split($answer, 4);

At this time, the $chunks array will contain:

 Array
(
    [0] => PHP
    [1] => PROG
    [2] => RAMM
    [3] => ING
)

Step 3: Output the split content to the web page

We can output the split string blocks to the web page to simulate the layout of the crossword game. For example, the following code will output these blocks into a simple grid with spaces between each block.

 echo "The answer to the game is：<br>";
foreach ($chunks as $chunk) {
    echo $chunk . " ";
}

Output result:

 The answer to the game is：
PHP PROG RAMM ING

Practical Application: Building the puzzle part of the crossword game

To better show how str_split is applied, we can design a more complex crossword game with a crossword puzzle section and an answer section. By adjusting the output layout, players can fill in the correct characters on the crossword board according to the prompts.

 $answer = "PHPISFUN";
$chunks = str_split($answer, 1);

// Generate puzzles（Here simply use underscore instead of letters）
$puzzle = str_repeat("_", strlen($answer));

echo "Puzzle：<br>" . $puzzle . "<br><br>";
echo "Answer：<br>";
foreach ($chunks as $chunk) {
    echo $chunk . " ";
}

This code will output:

 Puzzle：
________
Answer：
P H P I S F U N

In this way, you can create a basic crossword framework. In actual development, you can expand the game logic according to your needs, such as adding prompt functions, checking the correctness of player input, etc.

Summarize

The str_split function is a very convenient tool in PHP that can help you quickly split strings into small pieces of a specified length. With simple string manipulation, you can easily make a basic framework for crosswords. I hope you can use this technique to design your own game and enjoy programming!

str_split