(PHP 4, PHP 5, PHP 7)
sprintf — Return a formatted string
Returns a string produced according to the formatting string
format.
formatThe format string is composed of zero or more directives: ordinary characters (excluding %) that are copied directly to the result, and conversion specifications, each of which results in fetching its own parameter. This applies to both sprintf() and printf().
Each conversion specification consists of a percent sign (%), followed by one or more of these elements, in order:
A type specifier that says what type the argument data should be treated as. Possible types:
Variables will be co-erced to a suitable type for the specifier:
| Type | Specifiers |
|---|---|
| string | s |
| integer | d, u, c, o, x, X, b |
| double | g, G, e, E, f, F |
Attempting to use a combination of the string and width specifiers with character sets that require more than one byte per character may result in unexpected results
The format string supports argument numbering/swapping. Here is an example:
Example #1 Argument swapping
<?php
$num = 5;
$location = 'tree';
$format = 'There are %d monkeys in the %s';
echo sprintf($format, $num, $location);
?>
Example #2 Argument swapping
<?php
$format = 'The %s contains %d monkeys';
echo sprintf($format, $num, $location);
?>
Example #3 Argument swapping
<?php
$format = 'The %2$s contains %1$d monkeys';
echo sprintf($format, $num, $location);
?>
Example #4 Argument swapping
<?php
$format = 'The %2$s contains %1$d monkeys.
That\'s a nice %2$s full of %1$d monkeys.';
echo sprintf($format, $num, $location);
?>
Example #5 Specifying padding character
<?php
echo sprintf("%'.9d\n", 123);
echo sprintf("%'.09d\n", 123);
?>
以上例程会输出：
......123 000000123
Example #6 Position specifier with other specifiers
<?php
$format = 'The %2$s contains %1$04d monkeys';
echo sprintf($format, $num, $location);
?>
以上例程会输出：
The tree contains 0005 monkeys
Note:
Attempting to use a position specifier greater than
PHP_INT_MAXwill result in sprintf() generating warnings.
The c type specifier ignores padding and width
args
...
Returns a string produced according to the formatting string
format, 或者在失败时返回 FALSE.
Example #7 printf(): various examples
<?php
$n = 43951789;
$u = -43951789;
$c = 65; // ASCII 65 is 'A'
// notice the double %%, this prints a literal '%' character
printf("%%b = '%b'\n", $n); // binary representation
printf("%%c = '%c'\n", $c); // print the ascii character, same as chr() function
printf("%%d = '%d'\n", $n); // standard integer representation
printf("%%e = '%e'\n", $n); // scientific notation
printf("%%u = '%u'\n", $n); // unsigned integer representation of a positive integer
printf("%%u = '%u'\n", $u); // unsigned integer representation of a negative integer
printf("%%f = '%f'\n", $n); // floating point representation
printf("%%o = '%o'\n", $n); // octal representation
printf("%%s = '%s'\n", $n); // string representation
printf("%%x = '%x'\n", $n); // hexadecimal representation (lower-case)
printf("%%X = '%X'\n", $n); // hexadecimal representation (upper-case)
printf("%%+d = '%+d'\n", $n); // sign specifier on a positive integer
printf("%%+d = '%+d'\n", $u); // sign specifier on a negative integer
?>
以上例程会输出：
%b = '10100111101010011010101101' %c = 'A' %d = '43951789' %e = '4.39518e+7' %u = '43951789' %u = '4251015507' %f = '43951789.000000' %o = '247523255' %s = '43951789' %x = '29ea6ad' %X = '29EA6AD' %+d = '+43951789' %+d = '-43951789'
Example #8 printf(): string specifiers
<?php
$s = 'monkey';
$t = 'many monkeys';
printf("[%s]\n", $s); // standard string output
printf("[%10s]\n", $s); // right-justification with spaces
printf("[%-10s]\n", $s); // left-justification with spaces
printf("[%010s]\n", $s); // zero-padding works on strings too
printf("[%'#10s]\n", $s); // use the custom padding character '#'
printf("[%10.10s]\n", $t); // left-justification but with a cutoff of 10 characters
?>
以上例程会输出：
[monkey] [ monkey] [monkey ] [0000monkey] [####monkey] [many monke]
Example #9 sprintf(): zero-padded integers
<?php
$isodate = sprintf("%04d-%02d-%02d", $year, $month, $day);
?>
Example #10 sprintf(): formatting currency
<?php
$money1 = 68.75;
$money2 = 54.35;
$money = $money1 + $money2;
// echo $money will output "123.1";
$formatted = sprintf("%01.2f", $money);
// echo $formatted will output "123.10"
?>
Example #11 sprintf(): scientific notation
<?php
$number = 362525200;
echo sprintf("%.3e", $number); // outputs 3.625e+8
?>