Print to console in PHP-PHP Tutorial-php.cn

In PHP, printing to the console is a common way of debugging and outputting information. With a few simple lines of code, we can output variable values, debugging information or prompt information on the console to facilitate programmers to debug code and troubleshoot problems. This article will introduce how to use different methods to print information to the console in PHP, helping developers better understand and utilize this feature. The following is the relevant content compiled by php editor Strawberry for everyone. I hope it will be helpful to everyone.

Use javascript console.log() in `php` to write to the console

We can use some JavaScript in PHP to write to the console. We use console.log() in JavaScript to write anything to the console. We can print console.log() from JavaScript in PHP using the echo statement. If we use a PHP variable as a parameter to console.log(), then the contents of the variable will be written to the console. We can use the is_array() function to check whether the variable to be printed is an array. If the element is an array, we can use the implode() function with , as delimiters to concatenate the array elements into a string.

For example, create a function write_to_console() that accepts a parameter $data. Store the $data variable in the new variable $console. Use the is_array() function to check whether the variable $console is an array. If the variable is an array, use the implode() function and concatenate the array elements using , as delimiters. Store the value in the $console variable. Then, within the script tag, use console.log() to log the $console variable. Then use the echo statement to print the JavaScript code. Outside the function, call the write_to_console() function with two different parameters. Provide the string Hello World! as the first parameter and the array [1,2,3] as the second parameter.

When we go into the web page and inspect the console from the Inspect Element option, we can see the data being written to the console. In this way, we can use helper functions to write to the console in PHP.

Sample code:

<code>
<code class="language-php hljs" data-lang="php"><span style="display:flex;"><span><span style="color:#666"><?</span>php
</span></span><span style="display:flex;"><span>
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">funct<strong class="keylink">io</strong>n</span> <span style="color:#00f">write_to_console</span>(<span style="color:#19177c">$data</span>) {
</span></span><span style="display:flex;"><span> <span style="color:#19177c">$console</span> <span style="color:#666">=</span> <span style="color:#19177c">$data</span>;
</span></span><span style="display:flex;"><span> <span style="color:#008000;font-weight:bold">if</span> (is_array(<span style="color:#19177c">$console</span>))
</span></span><span style="display:flex;"><span> <span style="color:#19177c">$console</span> <span style="color:#666">=</span> implode(<span style="color:#ba2121">&#39;,&#39;</span>, <span style="color:#19177c">$console</span>);
</span></span><span style="display:flex;"><span>
</span></span><span style="display:flex;"><span> <span style="color:#008000;font-weight:bold">echo</span> <span style="color:#ba2121">"<script>console.log('Console: "</span> <span style="color:#666">.</span> <span style="color:#19177c">$console</span> <span style="color:#666">.</span> <span style="color:#ba2121">"' );</script>"</span>;
</span></span><span style="display:flex;"><span>}
</span></span><span style="display:flex;"><span>write_to_console(<span style="color:#ba2121">"Hello World!"</span>);
</span></span><span style="display:flex;"><span>write_to_console([<span style="color:#666">1</span>,<span style="color:#666">2</span>,<span style="color:#666">3</span>]);
</span></span><span style="display:flex;"><span>
</span></span><span style="display:flex;"><span><span style="color:#bc7a00">?></span><span >
</span></span></span></code></code>

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Output:

<code>
<code class="language-text hljs" data-lang="text"><span style="display:flex;"><span>Console: Hello World! 
</span></span><span style="display:flex;"><span>Console: 1,2,3
</span></span></code></code>

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Writing to the console in PHP using the JavaScript `console.log()` and `<strong class="keylink">JSON</strong>_encode()` functions

We can write to the console in PHP using the <strong class="keylink">js</strong>on_encode() function with JavaScript console.log(). json_ecode() The function converts the given associative array to a JSON object and indexed array to a JSON array. We can use this function for data items that need to be written to the console.

For example, create a function write_to_console() with parameters $data. Inside the function, apply the json_encode() function to the $data variable and log it using console.log. Turn the entire expression into a string and save it in the $console variable. Then, use the sprintf() function to print the variable as sprintf('<script>%s</script>', $console); and assign the expression to $console. Finally, use the echo statement to print the $console variable. Outside the function, create an associative array on the variable $data and an indexed array on the variable $days. Then, call the write_to_console() function using these two variables as arguments.

Associative arrays are written as JSON objects, and index arrays are written as JSON arrays in the console. This is how we write to the console in PHP using the json_encode() function.

Sample code:

<code>
<code class="language-php hljs" data-lang="php"><span style="display:flex;"><span><span style="color:#666"><?</span>php
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">function</span> <span style="color:#00f">write_to_console</span>(<span style="color:#19177c">$data</span>) {
</span></span><span style="display:flex;"><span>
</span></span><span style="display:flex;"><span> <span style="color:#19177c">$console</span> <span style="color:#666">=</span> <span style="color:#ba2121">'console.log('</span> <span style="color:#666">.</span> json_encode(<span style="color:#19177c">$data</span>) <span style="color:#666">.</span> <span style="color:#ba2121">');'</span>;
</span></span><span style="display:flex;"><span> <span style="color:#19177c">$console</span> <span style="color:#666">=</span> sprintf(<span style="color:#ba2121">'<script>%s</script>'</span>, <span style="color:#19177c">$console</span>);
</span></span><span style="display:flex;"><span> <span style="color:#008000;font-weight:bold">echo</span> <span style="color:#19177c">$console</span>;
</span></span><span style="display:flex;"><span>}
</span></span><span style="display:flex;"><span><span style="color:#19177c">$data</span> <span style="color:#666">=</span> [ <span style="color:#ba2121">'foo'</span> <span style="color:#666">=></span> <span style="color:#ba2121">'bar'</span> ];
</span></span><span style="display:flex;"><span><span style="color:#19177c">$days</span> <span style="color:#666">=</span> <span style="color:#008000;font-weight:bold">array</span>(<span style="color:#ba2121">"Sun"</span>, <span style="color:#ba2121">"Mon"</span>, <span style="color:#ba2121">"Tue"</span>);
</span></span><span style="display:flex;"><span>write_to_console(<span style="color:#19177c">$data</span>);
</span></span><span style="display:flex;"><span>write_to_console(<span style="color:#19177c">$days</span>);
</span></span><span style="display:flex;"><span><span style="color:#bc7a00">?></span><span >
</span></span></span></code></code>

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Output:

<code>
<code class="language-text hljs" data-lang="text"><span style="display:flex;"><span>Object { foo: "bar" }
</span></span><span style="display:flex;"><span>Array(3) [ "Sun", "Mon", "Tue" ]
</span></span></code></code>

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