vsprintf

(PHP 4 >= 4.1.0, PHP 5, PHP 7, PHP 8)

vsprintf — 返回格式化字符串

说明

vsprintf(string $format, array $values): string

作用与 sprintf() 函数类似，但是接收一个数组参数，而不是一系列可变数量的参数。

参数

format

format 字符串通常由零或多个指令组成：普通字符（不包含 %）——直接复制到结果，转换规范——获取每个参数的结果。

转换规范遵循此原型： %[argnum$][flags][width][.precision]specifier.

Argnum

整数后跟美元符号 $，用于指定转换中要处理的参数数量。

标志
标志	说明
`-`	在指定字段宽度时左对齐，默认右对齐
`+`	正数的加号 `+`前缀，默认负数的前缀是负号。
(space)	空格填充结果。这是默认设置。
`0`	仅用 0 进行左侧数字填充。使用 `s` 标志符可以右侧填充。
`'`(char)	用字符（char）填充结果。

Width

要么是整数，表示转换结果应该有多少个字符（最少），要么是 *。如果使用 *，那么宽度将作为额外的整数值提供，位于格式化符号之前。

Precision

小数点 .，可选的后跟整数或者 *，其含义取决于格式化符号：

e、E、f、F 标志符：小数点后需要打印的位数（默认是 6）。
g、G、h、H 标志符：这是要打印的最大有效位数。
s 标志符：充当分界点，为字符串设置最大字符限制。

注意: 如果小数点没有明确的精度值，则假设是 0。如果使用 *，则精度将作为额外的整数值提供，位于格式化符号之前。

**标志符**
标志符	说明
`%`	字面意思的百分号字符。不需要参数。
`b`	参数视为整数并以二进制数字呈现。
`c`	参数视为整数并以 ASCII 字符呈现。
`d`	参数视为整数并以（有符号）十进制数字呈现。
`e`	参数当做科学符号处理（例如 1.2e+2）。
`E`	与 `e` 标志符相同，但使用大写字母（例如 1.2E+2）。
`f`	参数当做浮点数处理且作为浮点数呈现（locale aware）。
`F`	参数当做浮点数处理且作为浮点数呈现（non-locale aware）。
`g`	通用格式。 Let P equal the precision if nonzero, 6 if the precision is omitted, or 1 if the precision is zero. Then, if a conversion with style E would have an exponent of X: If P > X ≥ −4, the conversion is with style f and precision P − (X + 1). Otherwise, the conversion is with style e and precision P − 1.
`G`	Like the `g` specifier but uses `E` and `f`.
`h`	Like the `g` specifier but uses `F`. Available as of PHP 8.0.0.
`H`	Like the `g` specifier but uses `E` and `F`. Available as of PHP 8.0.0.
`o`	参数视为整数并以八进制数字来呈现。
`s`	参数视为字符串来呈现。
`u`	参数视为整数并以无符号十进制数字呈现。
`x`	参数视为整数并作为十六进制数字呈现（带小写字母）。
`X`	参数视为整数并作为十六进制数字呈现（带大写字母）。

警告

c 类型标志符忽略填充和宽度。

警告

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.

变量将会强制转换为适合标志符的类型：

**类型处理**
类型	标志符
string	`s`
int	`d`, `u`, `c`, `o`, `x`, `X`, `b`
float	`e`, `E`, `f`, `F`, `g`, `G`, `h`, `H`

values

返回值

根据 format 和数组参数返回处理后的字符串。

错误／异常

从 PHP 8.0.0 开始，如果参数个数为零，将抛出 ValueError。在 PHP 8.0.0 之前，会发出 E_WARNING。

从 PHP 8.0.0 开始，如果 [width] 小于零或大于 PHP_INT_MAX，则会抛出 ValueError。在 PHP 8.0.0 之前，会发出 E_WARNING。

从 PHP 8.0.0 开始，如果 [precision] 小于零或大于 PHP_INT_MAX，则会抛出 ValueError。在 PHP 8.0.0 之前，会发出 E_WARNING。

从 PHP 8.0.0 开始，当传递的参数少于所需的参数时会抛出 ValueError。在 PHP 8.0.0 之前，返回 false 并发出 E_WARNING。

更新日志

版本	说明
8.0.0	此函数失败时不再返回 `false`。
8.0.0	如果参数个数为零则抛出 ValueError；以前该函数则会发出 `E_WARNING`。
8.0.0	如果 `[width]` 小于零或大于 `PHP_INT_MAX`，则抛出 ValueError；以前该函数则会发出 `E_WARNING`。
8.0.0	如果 `[precision]` 小于零或大于 `PHP_INT_MAX`，则抛出 ValueError；以前该函数则会发出 `E_WARNING`。
8.0.0	当传递的参数少于所需的参数时抛出 ValueError；以前该函数则会发出 `E_WARNING`。

示例

示例 #1 vsprintf(): 前导 0 的整数

<?php
print vsprintf("%04d-%02d-%02d", explode('-', '1988-8-1'));
?>

以上示例会输出：

1988-08-01

参见

printf() - 输出格式化字符串
sprintf() - 返回格式化字符串
fprintf() - 将格式化后的字符串写入到流
vprintf() - 输出格式化字符串
vfprintf() - 将格式化字符串写入流
sscanf() - 根据指定格式解析输入的字符
fscanf() - 从文件中格式化输入
number_format() - 以千位分隔符方式格式化一个数字
date() - 格式化 Unix 时间戳

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用户贡献的备注 10 notes

down

spectrumcat ¶

8 years ago

Instead of inventing own functions in case you'd like to use array keys as placeholder names and replace corresponding array values in a string, just use the str_replace:

$string = 'Hello %name!';
$data = array(
  '%name' => 'John'
);

$greeting = str_replace(array_keys($data), array_values($data), $string);

down

Josef Kufner ¶

12 years ago

<?php

/**

 * Like vsprintf, but accepts $args keys instead of order index.

 * Both numeric and strings matching /[a-zA-Z0-9_-]+/ are allowed.

 *

 * Example: vskprintf('y = %y$d, x = %x$1.1f', array('x' => 1, 'y' => 2))

 * Result:  'y = 2, x = 1.0'

 *

 * $args also can be object, then it's properties are retrieved

 * using get_object_vars().

 *

 * '%s' without argument name works fine too. Everything vsprintf() can do

 * is supported.

 *

 * @author Josef Kufner <jkufner(at)gmail.com>

 */

function vksprintf($str, $args)

{

    if (is_object($args)) {

        $args = get_object_vars($args);

    }

    $map = array_flip(array_keys($args));

    $new_str = preg_replace_callback('/(^|[^%])%([a-zA-Z0-9_-]+)\$/',

            function($m) use ($map) { return $m[1].'%'.($map[$m[2]] + 1).'$'; },

            $str);

    return vsprintf($new_str, $args);

}

?>

down

crash ¶

3 years ago

Note that this function now throws an ValueError* as of PHP 8.0 if there is an error:

$ php -r 'var_dump(vsprintf("%d", []));'
> Fatal error: Uncaught ValueError: The arguments array must contain 1 items, 0 given in Command line code:1

*ValueError is new in PHP 8.0, so if you want to make your code compatible to PHP 7.x you should test that the arguments array has the correct length.

down

steven at nevvix dot com ¶

6 years ago

<?php
/**
 * Return a formatted string like vsprintf() with named placeholders.
 *
 * When a placeholder doesn't have a matching key in `$args`,
 *   the placeholder is returned as is to see missing args.
 * @param string $format
 * @param array $args
 * @param string $pattern
 * @return string
 */
function p($format, array $args, $pattern="/\{(\w+)\}/") {
    return preg_replace_callback($pattern, function ($matches) use ($args) {
        return @$args[$matches[1]] ?: $matches[0];
    }, $format);
}

$args = ["database"=>"people", "user"=>"staff", "pass"=>"pass123", "host"=>"localhost"];

// With PHP-like placeholders: the variable is embedded in a string "{$database}" but without the dollar sign
$format = <<<SQL
CREATE DATABASE IF NOT EXISTS {database};
GRANT ALL PRIVILEGES ON {database_name}.* TO '{user}'@'{host}';
SET PASSWORD = PASSWORD('{pass}');
SQL;
echo p($format, $args);
/*
Result:

CREATE DATABASE IF NOT EXISTS people;
GRANT ALL PRIVILEGES ON {database_name}.* TO 'staff'@'localhost';
SET PASSWORD = PASSWORD('pass123');

The `{database_name}` placeholder doesn't exist as a matching key in `$args` so it's returned as is.
*/

// With Ruby-like placeholders
$format = <<<SQL
CREATE DATABASE IF NOT EXISTS :database;
GRANT ALL PRIVILEGES ON :database_name.* TO ':user'@':host';
SET PASSWORD = PASSWORD(':pass');
SQL;
echo p($format, $args, "/:(\w+)/");
/*
Result:

CREATE DATABASE IF NOT EXISTS people;
GRANT ALL PRIVILEGES ON :database_name.* TO 'staff'@'localhost';
SET PASSWORD = PASSWORD('pass123');

The `:database_name` placeholder doesn't exist as a matching key in `$args` so it's returned as is.
*/

down

www dot wesley at gmail dot com ¶

16 years ago

vnsprintf is equal to vsprintf except for associative, signed or floating keys.

vnsprintf supports for example "%assocKey$05d", "%-2$'+10s" and "%3.2$05u", vsprintf doesn't

vnsprintf( '%2$d', $array) [2nd value] is equal to vsprintf( '%2$d', $array) [2nd value]
vnsprintf( '%+2$d', $array) [key = 2] is equal to vnsprintf( '%2.0$d', $array) [key = 2]
vnsprintf( '%+2$d', $array) [key = 2] is different of vsprintf( '%+2$d', $array) [unsupported]

When you use signed or floating keys, vnsprintf searchs for the signed truncated key of the original array

Note¹: vnsprintf does not support for example "%someKeyf" (floating number, key = someKey) or "%+03d" (signed decimal number, key = 3), you should use "%someKey$f" or "%+03$d" respectively.
Note²: "%+03d" (or "%1$+03d") will be interpreted as signed zero-padded decimal number

<?php
function vnsprintf( $format, array $data)
{
    preg_match_all( '/ (?<!%) % ( (?: [[:alpha:]_-][[:alnum:]_-]* | ([-+])? [0-9]+ (?(2) (?:\.[0-9]+)? | \.[0-9]+ ) ) ) \$ [-+]? \'? .? -? [0-9]* (\.[0-9]+)? \w/x', $format, $match, PREG_SET_ORDER | PREG_OFFSET_CAPTURE);
    $offset = 0;
    $keys = array_keys($data);
    foreach ( $match as &$value )
    {
        if ( ( $key = array_search( $value[1][0], $keys) ) !== FALSE || ( is_numeric( $value[1][0]) && ( $key = array_search( (int)$value[1][0], $keys) ) !== FALSE ) ) {
            $len = strlen( $value[1][0]);
            $format = substr_replace( $format, 1 + $key, $offset + $value[1][1], $len);
            $offset -= $len - strlen( $key);
        }
    }
    return vsprintf( $format, $data);
}

$examples = array(
    2.8=>'positiveFloat',    // key = 2 , 1st value
    -3=>'negativeInteger',    // key = -3 , 2nd value
    'my_name'=>'someString'    // key = my_name , 3rd value
);

echo vsprintf( "%%my_name\$s = '%my_name\$s'\n", $examples);    // [unsupported]
echo vnsprintf( "%%my_name\$s = '%my_name\$s'\n", $examples);    // output : "someString"

echo vsprintf( "%%2.5\$s = '%2.5\$s'\n", $examples);        // [unsupported]
echo vnsprintf( "%%2.5\$s = '%2.5\$s'\n", $examples);        // output : "positiveFloat"

echo vsprintf( "%%+2.5\$s = '%+2.5\$s'\n", $examples);        // [unsupported]
echo vnsprintf( "%%+2.5\$s = '%+2.5\$s'\n", $examples);        // output : "positiveFloat"

echo vsprintf( "%%-3.2\$s = '%-3.2\$s'\n", $examples);        // [unsupported]
echo vnsprintf( "%%-3.2\$s = '%-3.2\$s'\n", $examples);        // output : "negativeInteger"

echo vsprintf( "%%2\$s = '%2\$s'\n", $examples);            // output : "negativeInteger"
echo vnsprintf( "%%2\$s = '%2\$s'\n", $examples);            // output : [= vsprintf]

echo vsprintf( "%%+2\$s = '%+2\$s'\n", $examples);        // [unsupported]
echo vnsprintf( "%%+2\$s = '%+2\$s'\n", $examples);        // output : "positiveFloat"

echo vsprintf( "%%-3\$s = '%-3\$s'\n", $examples);        // [unsupported]
echo vnsprintf( "%%-3\$s = '%-3\$s'\n", $examples);        // output : "negativeInteger"
?>

down

jon at ardentcreative dot co dot uk ¶

18 years ago

This can be used for quick and dirty internationalization:

<?php
$GLOBALS['strings']['example'] = "There are %d people.";

// Loads a phrase from the translations list in lang/$lang/phrases.php
function t() {
    $args = func_get_args();
    $nArgs = func_num_args();
    
    $phrase = array_shift($args);
    $nArgs--;
    
    include_once("../lang/" . lang() . "/phrases.php");
    if (isset($GLOBALS['strings'][$phrase])) {
        return vsprintf($GLOBALS['strings'][$phrase], $args);
    } else {
        return '<span style="color: #ff0000">Untranslated string: ' . $phrase . '</span>';
    }
}
?>

down

Roadster ¶

18 years ago

Please note: The same functionality (sortof) can be attained between version 4.0.4 and 4.1.0 using call_user_func_array.

Example:

call_user_func_array("sprintf", $arg)

First element of $arg is the format. This rescued me in a situation where version 4.1.0 wasn't available.

down

dee jay simple zero07 at geemail dawt co ¶

11 years ago

Using a heredoc with vprintf:



<?php

$string = <<<THESTRING

I like the state of %1\$s <br />

I picked: %2\$d as a number, <br />

I also picked %2\$d as a number again <br />

%3\$s<br />

THESTRING;



$returnText = vprintf(  $string, array('Oregon','7','I Love Oregon')  );



echo $returnText;

?>

down

jed at NOSPAM dot jed dot bz ¶

20 years ago

vsprintf() accepts arrays with any keys, so the array_shift() technique is unnecessary when writing a printf-type function. Any parameters you require are easily unset from the array you retrieve with func_get_args():

<?php

function mysprintf($format) {
    $args = func_get_args();
    unset($args[0]); /* get rid of "$format" */
    return vsprintf($format, $args);
}

/* I use this technique in production code as follows: */
function logf($target, $string) {
    $args = func_get_args();
    unset($args[0], $args[1]);
    fprintf($GLOBALS['config']['logtargets'][$target],
        "[%s] %s\n", date('H:i'), wordwrap(vsprintf($string, $args), 75, '\n\r '));
}

/* e.g.:
    logf(DEBUG, "Oops! %s", mysql_error());
 */

?>

array_shift() and other costly array operations aren't required, as far as I know. I could be wrong.

down

ASchmidt at Anamera dot net ¶

6 years ago

It's necessary to clearly how to apply argument swapping when using an array of arguments. One might be tempted to use %0$ to reference $args[0].

In reality, the position specifier is always the array index+1:

$args[0]  is referenced by %1$...
$args[1]  is referenced by %2$... 
etc.

Similarly, the first subpattern of a RegEx match would be found in $matches[1], the second in $match[2], etc. However if the $matches array is used as arguments to vsprint(), then the position specifier is subpattern+1:

preg_match( $pattern, $subject, $matches );
vsprintf( 'Full Match = %1$s, first Subpattern = %2$s, second Subpattern = %3$s', $matches );