php 将数字显示为两位小数

Show a number to two decimal places

提问by Rich Bradshaw

What's the correct way to round a PHP string to two decimal places?

将 PHP 字符串四舍五入到两位小数的正确方法是什么？

$number = "520"; // It's a string from a database

$formatted_number = round_to_2dp($number);

echo $formatted_number;

The output should be 520.00;

输出应该是520.00;

How should the round_to_2dp()function definition be?

round_to_2dp()函数定义应该如何？

回答by Codemwnci

You can use number_format():

您可以使用number_format()：

return number_format((float)$number, 2, '.', '');

Example:

例子：

$foo = "105";
echo number_format((float)$foo, 2, '.', '');  // Outputs -> 105.00

This function returns a string.

此函数返回一个字符串。

回答by Somnath Muluk

Use round()(use if you are expecting a number in float format only, else use number_format() as an answer given by Codemwnci):

使用round()（如果您只需要浮点格式的数字，请使用，否则使用 number_format() 作为Codemwnci 给出的答案）：

echo round(520.34345, 2);   // 520.34
echo round(520.3, 2);       // 520.3
echo round(520, 2);         // 520

From the manual:

从手册：

Description:

float round(float $val [, int $precision = 0 [, int $mode = PHP_ROUND_HALF_UP ]]);

Returns the rounded value of valto specified precision(number of digits after the decimal point). precisioncan also be negative or zero (default).

描述：

float round(float $val [, int $precision = 0 [, int $mode = PHP_ROUND_HALF_UP ]]);

返回val指定的舍入值precision（小数点后的位数）。precision也可以是负数或零（默认）。

...

...

Example #1 round()examples

<?php
    echo round(3.4);         // 3
    echo round(3.5);         // 4
    echo round(3.6);         // 4
    echo round(3.6, 0);      // 4
    echo round(1.95583, 2);  // 1.96
    echo round(1241757, -3); // 1242000
    echo round(5.045, 2);    // 5.05
    echo round(5.055, 2);    // 5.06
?>

Example #2 mode examples

<?php
    echo round(9.5, 0, PHP_ROUND_HALF_UP);   // 10
    echo round(9.5, 0, PHP_ROUND_HALF_DOWN); // 9
    echo round(9.5, 0, PHP_ROUND_HALF_EVEN); // 10
    echo round(9.5, 0, PHP_ROUND_HALF_ODD);  // 9

    echo round(8.5, 0, PHP_ROUND_HALF_UP);   // 9
    echo round(8.5, 0, PHP_ROUND_HALF_DOWN); // 8
    echo round(8.5, 0, PHP_ROUND_HALF_EVEN); // 8
    echo round(8.5, 0, PHP_ROUND_HALF_ODD);  // 9
?>

示例 #1round()示例

<?php
    echo round(3.4);         // 3
    echo round(3.5);         // 4
    echo round(3.6);         // 4
    echo round(3.6, 0);      // 4
    echo round(1.95583, 2);  // 1.96
    echo round(1241757, -3); // 1242000
    echo round(5.045, 2);    // 5.05
    echo round(5.055, 2);    // 5.06
?>

Example #2 模式示例

<?php
    echo round(9.5, 0, PHP_ROUND_HALF_UP);   // 10
    echo round(9.5, 0, PHP_ROUND_HALF_DOWN); // 9
    echo round(9.5, 0, PHP_ROUND_HALF_EVEN); // 10
    echo round(9.5, 0, PHP_ROUND_HALF_ODD);  // 9

    echo round(8.5, 0, PHP_ROUND_HALF_UP);   // 9
    echo round(8.5, 0, PHP_ROUND_HALF_DOWN); // 8
    echo round(8.5, 0, PHP_ROUND_HALF_EVEN); // 8
    echo round(8.5, 0, PHP_ROUND_HALF_ODD);  // 9
?>

回答by Marc B

Alternatively,

或者，

$padded = sprintf('%0.2f', $unpadded); // 520 -> 520.00

回答by SystemX17

http://php.net/manual/en/function.round.php

http://php.net/manual/en/function.round.php

e.g.

例如

echo round(5.045, 2);    // 5.05

echo round(5.055, 2);    // 5.06

回答by Biju

Try:

尝试：

$number = 1234545454; 
echo  $english_format_number = number_format($number, 2); 

The output will be:

输出将是：

1,234,545,454.00

回答by Aditya P Bhatt

You can use the PHP printfor sprintffunctions:

您可以使用 PHPprintf或sprintf函数：

Example with sprintf:

示例sprintf：

$num = 2.12;
echo sprintf("%.3f", $num);

You can run the same without echoas well. Example: sprintf("%.3f", $num);

您也可以在没有的情况下运行相同的程序echo。例子：sprintf("%.3f", $num);

Output:

输出：

2.120

Alternatively, with printf:

或者，使用printf：

echo printf("%.2f", $num);

Output:

输出：

2.124

回答by powtac

Another more exotic way to solve this issue is to use bcadd()with a dummy value for the $right_operand of 0.

解决此问题的另一种更奇特的方法是对bcadd()$right_operand使用虚拟值0。

$formatted_number = bcadd($number, 0, 2);

回答by Sani Kamal

Use the PHP number_format()function.

使用 PHP number_format()函数。

For example,

例如，

$num = 7234545423;
echo number_format($num, 2);

The output will be:

输出将是：

7,234,545,423.00

回答by Shamim Hafiz

Use the PHP number_format()function.

使用 PHP number_format()函数。

回答by ajreal

round_to_2dpis a user-defined function, and nothing can be done unless you posted the declaration of that function.

round_to_2dp是用户定义的函数，除非您发布该函数的声明，否则无法执行任何操作。

However, my guess is doing this: number_format($number, 2);

但是，我的猜测是这样做： number_format($number, 2);