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PHP vsprintf() Function

< PHP String Reference

Example

Write a formatted string to a variable:

<?php
$number = 9;
$str = "Beijing";
$txt = vsprintf("There are %u million bicycles in %s.",array($number,$str));
echo $txt;
?>
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Definition and Usage

The vsprintf() function writes a formatted string to a variable.

Unlike sprintf() , the arguments in vsprintf() , are placed in an array. The array elements will be inserted at the percent (%) signs in the main string. This function works "step-by-step". At the first % sign, the first array element is inserted, at the second % sign, the second array element is inserted, etc.

Note: If there are more % signs than arguments, you must use placeholders. A placeholder is inserted after the % sign, and consists of the argument- number and "\$". See example two.

Tip: Related functions: fprintf(), vfprintf(), printf(), sprintf() and vprintf().


Syntax

vsprintf(format,argarray)

Parameter Description
format Required. Specifies the string and how to format the variables in it.

Possible format values:

  • %% - Returns a percent sign
  • %b - Binary number
  • %c - The character according to the ASCII value
  • %d - Signed decimal number (negative, zero or positive)
  • %e - Scientific notation using a lowercase (e.g. 1.2e+2)
  • %E - Scientific notation using a uppercase (e.g. 1.2E+2)
  • %u - Unsigned decimal number (equal to or greather than zero)
  • %f - Floating-point number (local settings aware)
  • %F - Floating-point number (not local settings aware)
  • %g - shorter of %e and %f
  • %G - shorter of %E and %f
  • %o - Octal number
  • %s - String
  • %x - Hexadecimal number (lowercase letters)
  • %X - Hexadecimal number (uppercase letters)

Additional format values. These are placed between the % and the letter (example %.2f):

  • + (Forces both + and - in front of numbers. By default, only negative numbers are marked)
  • ' (Specifies what to use as padding. Default is space. Must be used together with the width specifier. Example: %'x20s (this uses "x" as padding)
  • - (Left-justifies the variable value)
  • [0-9] (Specifies the minimum width held of to the variable value)
  • .[0-9] (Specifies the number of decimal digits or maximum string length)

Note: If multiple additional format values are used, they must be in the same order as above.

argarray Required. An array with arguments to be inserted at the % signs in the format string

Technical Details

Return Value: Returns array values as a formatted string
PHP Version: 4.1.0+

More Examples

Example 1

Using the format value %f:

<?php
$num1 = 123;
$num2 = 456;
$txt = vsprintf("%f%f",array($num1,$num2));
echo $txt;
?>
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Example 2

Use of placeholders:

<?php
$number = 123;
$txt = vsprintf("With 2 decimals: %1\$.2f
<br>With no decimals: %1\$u",array($number));
echo $txt;
?>
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Example 3

Using sprintf() to demonstrate all possible format values:

<?php
$num1 = 123456789;
$num2 = -123456789;
$char = 50; // The ASCII Character 50 is 2

// Note: The format value "%%" returns a percent sign
echo sprintf("%%b = %b",$num1)."<br>"; // Binary number
echo sprintf("%%c = %c",$char)."<br>"; // The ASCII Character
echo sprintf("%%d = %d",$num1)."<br>"; // Signed decimal number
echo sprintf("%%d = %d",$num2)."<br>"; // Signed decimal number
echo sprintf("%%e = %e",$num1)."<br>"; // Scientific notation (lowercase)
echo sprintf("%%E = %E",$num1)."<br>"; // Scientific notation (uppercase)
echo sprintf("%%u = %u",$num1)."<br>"; // Unsigned decimal number (positive)
echo sprintf("%%u = %u",$num2)."<br>"; // Unsigned decimal number (negative)
echo sprintf("%%f = %f",$num1)."<br>"; // Floating-point number (local settings aware)
echo sprintf("%%F = %F",$num1)."<br>"; // Floating-point number (not local sett aware)
echo sprintf("%%g = %g",$num1)."<br>"; // Shorter of %e and %f
echo sprintf("%%G = %G",$num1)."<br>"; // Shorter of %E and %f
echo sprintf("%%o = %o",$num1)."<br>"; // Octal number
echo sprintf("%%s = %s",$num1)."<br>"; // String
echo sprintf("%%x = %x",$num1)."<br>"; // Hexadecimal number (lowercase)
echo sprintf("%%X = %X",$num1)."<br>"; // Hexadecimal number (uppercase)
echo sprintf("%%+d = %+d",$num1)."<br>"; // Sign specifier (positive)
echo sprintf("%%+d = %+d",$num2)."<br>"; // Sign specifier (negative)
?>
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Example 4

A demonstration of string specifiers:

<?php
$str1 = "Hello";
$str2 = "Hello world!";

echo vsprintf("[%s]",array($str1))."<br>";
echo vsprintf("[%8s]",array($str1))."<br>";
echo vsprintf("[%-8s]",array($str1))."<br>";
echo vsprintf("[%08s]",array($str1))."<br>";
echo vsprintf("[%'*8s]",array($str1))."<br>";
echo vsprintf("[%8.8s]",array($str2))."<br>";
?>
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< PHP String Reference