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Funktionen zur Behandlung von Variablen

<<settype

unserialize>>

strval

(PHP 4, PHP 5)

strvalErmittelt die String-Repräsentation einer Variable

Beschreibung

string strval ( mixed $var )

Gibt die String-Repräsentation einer Variablen zurück. Lesen Sie die Dokumentation über den Typ string, um weitere Informationen über das Konvertieren in Strings zu erhalten.

Diese Funktion führt keine Formatierung auf dem zurückgegebenen Wert durch. Wenn Sie nach einem Weg suchen, einen numerischen Wert als String zu formatieren, lesen Sie bitte die Dokumentation zu sprintf() oder number_format().

Parameter-Liste

var

Die nach string zu konvertierende Variable.

var darf jeder skalare Datentyp sein. Sie können strval() jedoch nicht auf Arrays oder Objekte anwenden.

Rückgabewerte

Die String-Repräsentation des Wertes von var.

Beispiele

Beispiel #1 strval()-Beispiel für die Verwendung der magischen PHP-Methode __toString

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

// Gibt 'StrValTest' aus
echo strval(new StrValTest);
?>

Siehe auch


10 BenutzerBeiträge:
- Beiträge aktualisieren...
Hayley Watson
22.08.2007 5:53
As of PHP 5.2, strval() will return the string value of an object, calling its __toString() method to determine what that value is.
NyctoFixer at gmail dot com
11.06.2007 21:19
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);
}

?>
kendsnyder+phpnet at gmail dot com
2.06.2007 7:08
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
portos_ze_retour at hotmail dot fr
10.03.2006 17:15
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>';
anthony dot parsons at manx dot net
9.01.2006 18:59
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 )
?>
php at ianco dot co dot uk
7.10.2005 13:36
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.
Steve Ball
9.09.2005 4:18
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.
brettsg at serialio dot com
2.08.2005 18:07
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)
Redbeard
24.08.2004 23:40
You can also use the PEAR package Numbers_Words, which handles many other languages.
Tom Nicholson
28.04.2004 18:13
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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