PHP 5.6.0 released

strval

(PHP 4, PHP 5)

strvalGet string value of a variable

Description

string strval ( mixed $var )

Get the string value of a variable. See the documentation on string for more information on converting to string.

This function performs no formatting on the returned value. If you are looking for a way to format a numeric value as a string, please see sprintf() or number_format().

Parameters

var

The variable that is being converted to a string.

var may be any scalar type or an object that implements the __toString() method. You cannot use strval() on arrays or on objects that do not implement the __toString() method.

Return Values

The string value of var.

Examples

Example #1 strval() example using PHP 5's magic __toString() method.

<?php
class StrValTest
{
    public function 
__toString()
    {
        return 
__CLASS__;
    }
}

// Prints 'StrValTest'
echo strval(new StrValTest);
?>

See Also

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User Contributed Notes 8 notes

up
3
Hayley Watson
7 years ago
As of PHP 5.2, strval() will return the string value of an object, calling its __toString() method to determine what that value is.
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2
Steve Ball
8 years ago
It seems that one is being treated as an unsigned large int (32 bit), and the other as a signed large int (which has rolled over/under).

2326201276 - (-1968766020) =  4294967296.
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2
portos_ze_retour at hotmail dot fr
8 years ago
In complement to Tom Nicholson's contribution, here is the french version (actually it's possible to change the language, but you should check the syntax ;) )

function int_to_words($x) {
   global $nwords;

   if(!is_numeric($x))
     $w = '#';
   else if(fmod($x, 1) != 0)
     $w = '#';
   else {
     if($x < 0) {
         $w = $nwords['minus'].' ';
         $x = -$x;
     } else
         $w = '';
     // ... now $x is a non-negative integer.

     if($x < 21)  // 0 to 20
         $w .= $nwords[$x];
     else if($x < 100) {  // 21 to 99
         $w .= $nwords[10 * floor($x/10)];
         $r = fmod($x, 10);
         if($r > 0)
           $w .= '-'. $nwords[$r];
     } else if($x < 1000) {  // 100 to 999
         $w .= $nwords[floor($x/100)] .' '.$nwords['hundred'];
         $r = fmod($x, 100);
         if($r > 0)
           $w .= ' '.$nwords['separator'].' '. int_to_words($r);
     } else if($x < 1000000) {  // 1000 to 999999
         $w .= int_to_words(floor($x/1000)) .' '.$nwords['thousand'];
         $r = fmod($x, 1000);
         if($r > 0) {
           $w .= ' ';
           if($r < 100)
               $w .= $nwords['separator'].' ';
           $w .= int_to_words($r);

         }
     } else {    //  millions
         $w .= int_to_words(floor($x/1000000)) .' '.$nwords['million'];
         $r = fmod($x, 1000000);
         if($r > 0) {
           $w .= ' ';
           if($r < 100)
               $word .= $nwords['separator'].' ';
           $w .= int_to_words($r);
         }
     }
   }
   return $w;
}

// Usage in English
$nwords = array( "zero", "one", "two", "three", "four", "five", "six", "seven",
                   "eight", "nine", "ten", "eleven", "twelve", "thirteen",
                   "fourteen", "fifteen", "sixteen", "seventeen", "eighteen",
                   "nineteen", "twenty", 30 => "thirty", 40 => "forty",
                   50 => "fifty", 60 => "sixty", 70 => "seventy", 80 => "eighty",
                   90 => "ninety" , "hundred" => "hundred", "thousand"=> "thousand", "million"=>"million",
                   "separator"=>"and", "minus"=>"minus");

echo 'There are currently '. int_to_words(-120223456) . ' members logged on.<br>';

//Utilisation en Francais
$nwords = array( "zéro", "un", "deux", "trois", "quatre", "cinq", "six", "sept",
                   "huit", "neuf", "dix", "onze", "douze", "treize",
                   "quatorze", "quinze", "seize", "dix-sept", "dix-huit",
                   "dix-neuf", "vingt", 30 => "trente", 40 => "quarante",
                   50 => "cinquante", 60 => "soixante", 70 => "soixante-dix", 80 => "quatre-vingt",
                   90 => "quatre-vingt-dix" , "hundred" => "cent", "thousand"=> "mille", "million"=>"million",
                   "separator"=>"", "minus"=>"moins");

echo 'Il y a actuellement '. int_to_words(-120223456) . ' membres connectés.<br>';
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2
kendsnyder+phpnet at gmail dot com
7 years ago
The only way to convert a large float to a string is to use printf('%0.0f',$float); instead of strval($float); (php 5.1.4).

// strval() will lose digits around pow(2,45);
echo pow(2,50); // 1.1258999068426E+015
echo (string)pow(2,50); // 1.1258999068426E+015
echo strval(pow(2,50)); // 1.1258999068426E+015

// full conversion
printf('%0.0f',pow(2,50)); // 112589906846624
echo sprintf('%0.0f',pow(2,50)); // 112589906846624
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1
php at ianco dot co dot uk
8 years ago
I can't help being surprised that

(string)"0" == (string)"0.00"

evaluates to true. It's the same with strval and single quotes.
=== avoids it.

Why does it matter? One of my suppliers, unbelievably, uses 0 to mean standard discount and 0.00 to mean no discount in their stock files.
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0
anthony dot parsons at manx dot net
8 years ago
If you have to compare object variables like this be careful not to make a typo, or you could end up calling __set() -
<?php
/* Does what you'd expect it to */
if ( $user->password == $user2->password )

/* Doesn't */
if ( $user->password = $user2->password )
?>

To avoid that ever happening, do it like this:
<?php
if ( strval($user->password) == $user2->password )
?>
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-1
NyctoFixer at gmail dot com
7 years ago
As of PHP 5.1.4 (I have not tested it in later versions), the strval function does not attempt to invoke the __toString method when it encounters an object. This simple wrapper function will handle this circumstance for you:

<?

/**
* Returns the string value of a variable
*
* This differs from strval in that it invokes __toString if an object is given
* and the object has that method
*/
function stringVal ($value)
{
   
// We use get_class_methods instead of method_exists to ensure that __toString is a public method
   
if (is_object($value) && in_array("__toString", get_class_methods($value)))
        return
strval($value->__toString());
    else
        return
strval($value);
}

?>
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-1
Tom Nicholson
10 years ago
If you want to convert an integer into an English word string, eg. 29 -> twenty-nine, then here's a function to do it.

Note on use of fmod()
  I used the floating point fmod() in preference to the % operator, because % converts the operands to int, corrupting values outside of the range [-2147483648, 2147483647]

I haven't bothered with "billion" because the word means 10e9 or 10e12 depending who you ask.

The function returns '#' if the argument does not represent a whole number.

<?php
$nwords
= array( "zero", "one", "two", "three", "four", "five", "six", "seven",
                  
"eight", "nine", "ten", "eleven", "twelve", "thirteen",
                  
"fourteen", "fifteen", "sixteen", "seventeen", "eighteen",
                  
"nineteen", "twenty", 30 => "thirty", 40 => "forty",
                  
50 => "fifty", 60 => "sixty", 70 => "seventy", 80 => "eighty",
                  
90 => "ninety" );

function
int_to_words($x) {
   global
$nwords;

   if(!
is_numeric($x))
     
$w = '#';
   else if(
fmod($x, 1) != 0)
     
$w = '#';
   else {
      if(
$x < 0) {
        
$w = 'minus ';
        
$x = -$x;
      } else
        
$w = '';
     
// ... now $x is a non-negative integer.

     
if($x < 21)   // 0 to 20
        
$w .= $nwords[$x];
      else if(
$x < 100) {   // 21 to 99
        
$w .= $nwords[10 * floor($x/10)];
        
$r = fmod($x, 10);
         if(
$r > 0)
           
$w .= '-'. $nwords[$r];
      } else if(
$x < 1000) {   // 100 to 999
        
$w .= $nwords[floor($x/100)] .' hundred';
        
$r = fmod($x, 100);
         if(
$r > 0)
           
$w .= ' and '. int_to_words($r);
      } else if(
$x < 1000000) {   // 1000 to 999999
        
$w .= int_to_words(floor($x/1000)) .' thousand';
        
$r = fmod($x, 1000);
         if(
$r > 0) {
           
$w .= ' ';
            if(
$r < 100)
              
$w .= 'and ';
           
$w .= int_to_words($r);
         }
      } else {   
//  millions
        
$w .= int_to_words(floor($x/1000000)) .' million';
        
$r = fmod($x, 1000000);
         if(
$r > 0) {
           
$w .= ' ';
            if(
$r < 100)
              
$word .= 'and ';
           
$w .= int_to_words($r);
         }
      }
   }
   return
$w;
}

?>

Usage:
<?php
echo 'There are currently '. int_to_words($count) . ' members logged on.';
?>
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