settype
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
strval
(PHP 4, PHP 5)
strval — Récupère la valeur d'une variable, au format chaîne
Description
Récupère la valeur de la variable var,
au format chaîne de caractères. Voir la documentation sur les
chaînes de caractères pour plus d'informations sur la conversion
en chaîne.
Cette fonction n'effectue aucun formatage sur la valeur retournée. Si vous cherchez un moyen de formatter une valeur numérique en chaîne de caractères, reportez-vous à la fonction sprintf() ou la fonction number_format().
Liste de paramètres
-
var -
La variable à convertir en chaîne de caractères.
varpeut être un scalaire ou un objet implémentant la méthode magique __toString(). Vous ne pouvez pas utiliser la fonction strval() avec des tableaux ou des objets qui n'implémentent pas la méthode magique __toString().
Valeurs de retour
La valeur de la variable var sous la forme d'une chaîne de caractères.
Exemples
Exemple #1 Exemple pour strval() utilisant la méthode magique PHP 5 __toString().
<?php
class StrValTest
{
public function __toString()
{
return __CLASS__;
}
}
// Affiche 'StrValTest'
echo strval(new StrValTest);
?>
Voir aussi
- boolval() - Récupère la valeur booléenne d'une variable
- floatval() - Convertit une chaîne en nombre à virgule flottante
- intval() - Retourne la valeur numérique entière équivalente d'une variable
- settype() - Affecte un type à une variable
- sprintf() - Retourne une chaîne formatée
- number_format() - Formate un nombre pour l'affichage
- Le transtypage
- __toString()
add a note
User Contributed Notes
strval - [10 notes]
kendsnyder+phpnet at gmail dot com ¶
5 years ago
Steve Ball ¶
7 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.
Hayley Watson ¶
5 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.
php at ianco dot co dot uk ¶
7 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.
anthony dot parsons at manx dot net ¶
7 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 )
?>
Tom Nicholson ¶
9 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.';
?>
portos_ze_retour at hotmail dot fr ¶
7 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>';
brettsg at serialio dot com ¶
7 years ago
How come this code in version 4.4 does something different than in version 4.3?
$val = 538759009 ^ 0xAABBCCDD;
print "val=" . $val;
= 2326201276 (version 4.4)
and
= -1968766020 (version 4.3)
NyctoFixer at gmail dot com ¶
5 years ago
As of PHP 5.1.4 (I have not tested it in later versions), the strval function does not attempt to invoke the __toString method when it encounters an object. This simple wrapper function will handle this circumstance for you:
<?
/**
* Returns the string value of a variable
*
* This differs from strval in that it invokes __toString if an object is given
* and the object has that method
*/
function stringVal ($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);
}
?>