How to print a string that also contains an array?

[E_Leeder]

If I wanted to print a string that contains a variable that also contains an array, how would I do so? I want to put the resulting echo into a log file.

Example: “These are the books: $userArray and these are the pages: $pagesArray”;

With just an array, I can use print_r($array, true) to get an array formatted for use in a string (which works well for my purposes) but this doesn’t work with two arrays unless I do this manually. (Such as setting the $user_array = print_r($userArray). But I want to write a function that will take a string, potentially containing arrays  (as variables), and interpolate/make them legible for  humans. (Some of the arrays are also multidimensional.)

But it looks like I can't even concatenate a string and an array. $string = $string . $array. gives an error, array to string conversion.


I don’t understand PHP very well so please explain what is going on here. and the best way to record something like the Example above.
 

[jcbones]

Use the second argument to print array.

 

 

echo 'These are the books: ' . print_r($userArray,true) . ' and these are the pages: ' . print_r($pagesArray,true);

Edited October 25, 2014 by jcbones

[E_Leeder]

Thanks, I should have thought of that.

 

But I guess there is no way to have a variable that contains an array in a string because of the string to array conversion error?

 

So a function like this is impossible?

$variable = “These are the books: $userArray and these are the pages: $pagesArray”; // (double or single quoted)

function usePrint_rOnAllArraysInString($variable) {

// do the magic print_r on all arrays in the variable passed
return $variable // all arrays in the string flattened into something like print_r does

}

Edited October 25, 2014 by E_Leeder

[Knoxxy]

Id use implode to add all the values to your string.

 

http://php.net/manual/en/function.implode.php

[jcbones]

Do you mean like:

function printArray(array $arr) {
 $op = null;
 foreach($arr as $key=>$val) {
  if(is_array($val)) {
   $op .= printArray($val);
  } else {
  $op .= $key . ': ' . $val . '<br />';
  }
 return $op;
}

[E_Leeder]

Yes, very close to something like that, thanks. Except that I'd like to prepend a string to each array print out, and have the ability to put multiple string/array combinations in the function.

 

I have a better idea of what would be necessary now, thanks to you example.

 

(The data doesn't make sense, just using it as an example.)

$string1 = 'There are the books: ';
$array1 = ('book1', 'book2', 'book3');

$string2 = 'There are the pages: ';
$array2 = ('page1', 'page2', 'page3');



function printArray($string, $array, $string2, $array2) {
// do the work

return $string;
}

But how would I make a function take an indefinite number of arguments? I googled it and came up and func_get_args().

 

So would there be any problems with this?

function printArray($args) {
  $args = func_get_args()
  $string = '';
  foreach ($args as $arg) {
   if (is_array($arg) {
    $string .= print_r($arg, true);
   }
   else {
   $string .= $arg;
   }
  }
return $string;
}

any problems with this code or ways to make it better?

Edited October 26, 2014 by E_Leeder

[Barand]

IMHO print_r() is a debugging function and not suitable for output to a web page for user consumption.

 

You might find it useful to have a couple of functions in your arsenal, such as

function bulletList($arr)
{
    return "<ul><li>" . join('</li><li>', $arr) . "</li></ul>\n";
}

function commaList($arr)
{
    $last = array_pop($arr);
    return join(', ', $arr) . " and $last";
}

Then can

$books = array (
        'Treasure Island',
        'Harry Potter and the Philosopher\'s Stone',
        'A Tale of Two Cities'
    );
$pages = array(23,45,135,247,248);
    
$sentence = "These are the books " . bulletList($books) . "and these are the pages " . commaList($pages);

and echoing $sentence gives

 

 

These are the books

• Treasure Island
• Harry Potter and the Philosopher's Stone
• A Tale of Two Cities

and these are the pages 23, 45, 135, 247 and 248

 

Edited October 26, 2014 by Barand

[E_Leeder]

Thanks for sharing, Barand. The string output I want doesn't need to be THAT legible for humans because it is just going in a log, and the log will be parsed. But if I do need to look at an individual log entry, I should be able to make sense of it (even if it takes a lot of effort).