(PHP 4, PHP 5)
sprintf — Return a formatted string
Returns a string produced according to the formatting string
format
.
format
The 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:
The format string supports argument numbering/swapping. Here is an example:
Example #1 Argument swapping
<?php
$num = 5;
$location = 'tree';
$format = 'There are %d monkeys in the %s';
printf($format, $num, $location);
?>
Example #2 Argument swapping
<?php
$format = 'The %s contains %d monkeys';
printf($format, $num, $location);
?>
Example #3 Argument swapping
<?php
$format = 'The %2$s contains %1$d monkeys';
printf($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$d monkeys.';
printf($format, $num, $location);
?>
Example #5 Position specifier with other specifiers
<?php
$format= 'The %2$s contains %1$04d monkeys';
printf($format, $num, $location);
?>
以上例程会输出:
The tree contains 0005 monkeys
args
...
Returns a string produced according to the formatting string
format
.
版本 | 说明 |
---|---|
4.0.6 | Support for argument numbering/swapping was added |
Example #6 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 #7 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 #8 sprintf(): zero-padded integers
<?php
$isodate = sprintf("%04d-%02d-%02d", $year, $month, $day);
?>
Example #9 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 #10 sprintf(): scientific notation
<?php
$number = 362525200;
echo sprintf("%.3e", $number); // outputs 3.625e+8
?>