print is not a function but a language construct. Its argument is the expression following the print keyword, and is not delimited by parentheses.
The major differences to echo are that print only accepts a single argument and always returns 1 .
Parameters
The expression to be output. Non-string values will be coerced to strings, even when the strict_types directive is enabled.
Return Values
Examples
Example #1 print examples
print «print does not require parentheses.» ;
// No newline or space is added; the below outputs «helloworld» all on one line
print «hello» ;
print «world» ;
print «This string spans
multiple lines. The newlines will be
output as well» ;
print «This string spans\nmultiple lines. The newlines will be\noutput as well.» ;
// The argument can be any expression which produces a string
$foo = «example» ;
print «foo is $foo » ; // foo is example
$fruits = [ «lemon» , «orange» , «banana» ];
print implode ( » and » , $fruits ); // lemon and orange and banana
// Non-string expressions are coerced to string, even if declare(strict_types=1) is used
print 6 * 7 ; // 42
// Because print has a return value, it can be used in expressions
// The following outputs «hello world»
if ( print «hello» ) echo » world» ;
>
// The following outputs «true»
( 1 === 1 ) ? print ‘true’ : print ‘false’ ;
?>
Notes
Note: Using with parentheses
Surrounding the argument to print with parentheses will not raise a syntax error, and produces syntax which looks like a normal function call. However, this can be misleading, because the parentheses are actually part of the expression being output, not part of the print syntax itself.
print( «hello» );
// also outputs «hello», because («hello») is a valid expression
print( 1 + 2 ) * 3 ;
// outputs «9»; the parentheses cause 1+2 to be evaluated first, then 3*3
// the print statement sees the whole expression as one argument
if ( print( «hello» ) && false ) print » — inside if» ;
>
else print » — inside else» ;
>
// outputs » — inside if»
// the expression («hello») && false is first evaluated, giving false
// this is coerced to the empty string «» and printed
// the print construct then returns 1, so code in the if block is run
?>
When using print in a larger expression, placing both the keyword and its argument in parentheses may be necessary to give the intended result:
if ( (print «hello» ) && false ) print » — inside if» ;
>
else print » — inside else» ;
>
// outputs «hello — inside else»
// unlike the previous example, the expression (print «hello») is evaluated first
// after outputting «hello», print returns 1
// since 1 && false is false, code in the else block is run
print «hello » && print «world» ;
// outputs «world1»; print «world» is evaluated first,
// then the expression «hello » && 1 is passed to the left-hand print
(print «hello » ) && (print «world» );
// outputs «hello world»; the parentheses force the print expressions
// to be evaluated before the &&
?>
Note: Because this is a language construct and not a function, it cannot be called using variable functions, or named arguments.
See Also
- echo — Output one or more strings
- printf() — Output a formatted string
- flush() — Flush system output buffer
- Ways to specify literal strings
Printing Reports from a PHP Browser: Tips and Tricks
To avoid allowing user input directly to your SQL statements, it is recommended to not include variables that are not constant in prepared statements. Alternatively, use single quotes as provided or attempt the following approach to achieve the desired output. Another solution is to use single quotes when printing special characters such as ‘$q_option’.$de. Additionally, it is important to remember to enclose $optionss within single quotes if its value should not be printed.
Codeigniter : how print response of page into log_message?
simply try something like this
$config['log_threshold'] = 2; and log_message('debug/error', 'your message'); class MY_Output extends CI_Output < protected $_enable_log_output = TRUE; public function __construct() < parent:: __construct(); log_message('debug', 'MY_Output Class Initialized'); >// -------------------------------------------------------------------- /** * Display Output * * Processes sends the sends finalized output data to the browser along * with any server headers and profile data. It also stops benchmark * timers so the page rendering speed and memory usage can be shown. * * Note: All "view" data is automatically put into $this->final_output * by controller class. * * @uses CI_Output::$final_output * @param string $output Output data override * @return void */ public function _display($output = '') < // Note: We use globals because we can't use $CI =& get_instance() // since this function is sometimes called by the caching mechanism, // which happens before the CI super object is available. global $BM, $CFG; // Grab the super object if we can. if (class_exists('CI_Controller', FALSE)) < $CI =& get_instance(); >// -------------------------------------------------------------------- // Set the output data if ($output === '') < $output =& $this->final_output; > // -------------------------------------------------------------------- // Is minify requested? if ($CFG->item('minify_output') === TRUE) < $output = $this->minify($output, $this->mime_type); > // -------------------------------------------------------------------- // Do we need to write a cache file? Only if the controller does not have its // own _output() method and we are not dealing with a cache file, which we // can determine by the existence of the $CI object above if ($this->cache_expiration > 0 && isset($CI) && ! method_exists($CI, '_output')) < $this->_write_cache($output); > // -------------------------------------------------------------------- // Parse out the elapsed time and memory usage, // then swap the pseudo-variables with the data $elapsed = $BM->elapsed_time('total_execution_time_start', 'total_execution_time_end'); if ($this->parse_exec_vars === TRUE) < $memory = round(memory_get_usage() / 1024 / 1024, 2).'MB'; $output = str_replace(array('0.0071', ''), array($elapsed, $memory), $output); > // -------------------------------------------------------------------- // Is compression requested? if ($CFG->item('compress_output') === TRUE && $this->_zlib_oc === FALSE && extension_loaded('zlib') && isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE) < ob_start('ob_gzhandler'); >// -------------------------------------------------------------------- // Are there any server headers to send? if (count($this->headers) > 0) < foreach ($this->headers as $header) < @header($header[0], $header[1]); >> // -------------------------------------------------------------------- // Print output in log if($this->_enable_log_output) < log_message('debug', $output); >// -------------------------------------------------------------------- // Does the $CI object exist? // If not we know we are dealing with a cache file so we'll // simply echo out the data and exit. if ( ! isset($CI)) < echo $output; log_message('debug', 'Final output sent to browser'); log_message('debug', 'Total execution time: '.$elapsed); return; >// -------------------------------------------------------------------- // Do we need to generate profile data? // If so, load the Profile class and run it. if ($this->enable_profiler === TRUE) < $CI->load->library('profiler'); if ( ! empty($this->_profiler_sections)) < $CI->profiler->set_sections($this->_profiler_sections); > // If the output data contains closing and tags // we will remove them and add them back after we insert the profile data $output = preg_replace('|.*?|is', '', $output, -1, $count).$CI->profiler->run(); if ($count > 0) < $output .= ''; >> // Does the controller contain a function named _output()? // If so send the output there. Otherwise, echo it. if (method_exists($CI, '_output')) < $CI->_output($output); > else < echo $output; // Send it to the browser! >log_message('debug', 'Final output sent to browser'); log_message('debug', 'Total execution time: '.$elapsed); > > /* End of file MY_Output.php */ /* Location: ./application/core/MY_Output.php */ Php — How to print a debug log?, Debugging in PHP is not done in a console environment. In PHP, you have 3 categories of debugging solutions: Output to a webpage (see dBug library for a nicer view of things). Write to a log file; In session debugging with xDebug; Learn to use those instead of trying to make PHP behave like whatever other language you are used to. Usage exampleerror_log(print_r($variable, TRUE));Feedback
How can i print reports from browser in php
While CSS Printing can be decent, it may not be the most dependable option. Instead, consider exploring generating PDF files in PHP, which involves using the FPDF library.
The printing functionality is handled by the browser, and not by any server-side code. To enable printing, you can create a button using HTML, which, when clicked, will print the page. It’s worth noting that some browsers may also print the button, depending on their configuration.
This is not necessarily a PHP problem since it can be resolved by implementing some CSS regulations.
The referenced resource is located at http://www.w3.org/TR/CSS2/media.html.
This includes all the necessary information, particularly about the media type called «print». 🙂
This is an edit to my previous comment, which was intended to respond to the comment above where the issue was explained further.
How can I correctly print the object content in PHP?, The problem is that into my log file I obtain this output: [2017-01-30 10:25:19] local.INFO: USER: so it is as this object is empty but I think that it is not empty because then is used.
PHP — How to print errors on login form on index page?
Before commencing, it’s essential to note that variables that are not constant should never be included in prepared statements. Doing so would mean that user input is being directly incorporated into your SQL statements.
To receive errors, it is recommended to utilize a simple die($db->error); in the database to return the error exactly where required.
At the conclusion of a connection, it is imperative to $db->close(); without fail.
Echo — How to print $ with php, Basically I have a block of html that I want to echo to the page and the html has the $ sign in it and the php thinks it is a variable so $1 is treated as the variable not the value and is not displayed. There is the standard answers here but none are working: PHP: How to get $ to print using echo
Unable to print $ in php
In case «q_option0», «q_option1», «q_option2» and so on are variables, their values can be referenced using $$ . This will result in the output of «abc». It is important to note that $optionss is assigned the value of $q_option0 and echoed simultaneously in this code.
$de = 0; $q_option0 = "abc"; $var = "q_option".$de; echo $optionss = $$var; It appears that the array $de was not processed. You may consider using a foreach or for loop to accomplish this task. Give it a try.
or use single quotes as given
$q_option1 $q_option2 $q_option3 $q_option4 To display special characters, employ the use of single quotations.
If you do not want the value of $optionss to be printed, make sure to enclose it within single quotes, which seems to have slipped your mind.
echo '$optionss= $q_option'.$de; // print the whole expression echo $optionss='$'."q_option".$val."
"; // assign right hand side of the expression to the variable '$optionss' and print that out // so you will only get output $q_option0, $q_option1. instead of $optionss=$q_option0, $optionss=$q_option1. The following is a solution provided for a problem other than the one I had initially thought.
It seems like the purpose is to generate variable names dynamically and retrieve their corresponding values.
To access the value of a variable inside another variable, you can create a temporary variable with the same name and use double $$ to retrieve its value. Is this clear?
$tmp = "q_option".$de; echo $optionss=$$tmp; How can I write to the console in PHP?, My solution in Windows: Setup a .txt file that is somewhat easily to get to and writable. Set the PHP error_log variable in the .ini file to write to that file. Open the file in Windows File Explorer and open a preview pane for it. Use the error_log (‘myTest’); PHP command to send messages.