如何使用正则表达式提取php中的数字？

Question

If I want to extract only "7.20" from "$ 7.20", how can I do?? I have try

preg_replace("[^0-9]", "", "$ 7.20");

but it is not work. It also shows $ 7.20... There is no difference...

Answer 1

preg_replace('/[^.0-9]/', "", "$ 7.20");

Your regex needs to be delimited, start and end. Commonly / is used as a delimiter.

What you have above: [^0-9]

The initial [ will be interpreted as a delimiter (in pair with ] at the end).

This was looking to replace 0-9 literally at the beginning of the string.

Answer 2

您也可以尝试sscanf ，通常更易于使用

sscanf( '$ 7.20', '$ %f' );