substr 以逗号生效

Question

我有输入"Weight: 123,4 kg" 我想将号码保存到数据库中。所以我有这样的代码 substr

 $_POST['product_weight'] = 
substr($_POST['product_weight'], 8, 3);
str_replace(',','',$_POST['product_weight']);

但现在的问题是，输出总是“123.00”。是 substr 还是数据类型的错误？

我的表格

<input type="text" class='numbering' name="product_weight" value="<?=(!empty($form['product_weight']))?number_format($form['product_weight'],2):''?>">

输出

<td><?=(!empty($each->product_weight))?number_format($each->product_weight,2).' gr':'-';?></td>

Answer 1

此代码 substr($_POST['product_weight'], 8, 3) 表示 "return 3 characters starting at index 8 in the $_POST value" - 因此您捕获的只是 123，而不是值的小数部分。

Answer 2

试试这个，如果你的逗号是小数点参考这个Converting a number with comma as decimal point to float

逗号作为小数点，live demo.

<?php
$string = 'Weight: 123,4 kg';
echo number_format(floatval(str_replace(',', '.', substr($string, 8))),2);

逗号作为分隔符，live demo

<?php
$string = 'Weight: 123,4 kg';
echo number_format(floatval(str_replace(',', '', substr($string, 8))),2);

Answer 3

$string = 'Weight: 123,4 kg';
$arr_string = explode(" ", $string);
echo $arr_string['1'];   //Output : 123,4
echo str_replace(",", ".", $arr_string['1']);  //Output : 123.4

substr 以逗号生效

Substr take effect with comma

php

mysql

comma

substr