Question

can you explain this regular expression.

$price = "...555.55";
$price  = preg_replace('/^./', '', $price);

output:

 $price = ..555.55;

Answer 1

The regex '/^./' matches any character at the beginning of the string.

• dot(.) matches any character except the newline character, and
• caret(^) is used to match at the beginning.

So, your preg_replace is replacing any character at the beginning with an empty string.
So, ...555.55 becomes ..555.55 after replacing the first ..

If you just want to replace all the dots(.) from the beginning, then you have to escape the . in your regex. Since simply using . will match any character. Also, you need to use some quantifier – * or + to replace more dots(.).

So, your regex would be:

preg_replace('/^[.]+/', '', $price);

or:

preg_replace('/^\.+/', '', $price);