Re: Catch line indetation

> Date: Friday, October 28, 2016 12:09:31 +0100 > From: Ashley Sheridan <ash@ashleysheridan.co.uk> > > On 28 October 2016 12:01:16 BST, Narcis Garcia > <informatica@actiu.net> wrote: >> Hello, I have a string (I quote here only) as: >> >> ' <table>...</table>' >> >> As you can see there are 3 spaces at the beginning, but it could >> be 0 or >> 4 or any number of spaces. >> How can I get a string with only the initial spaces part? >> >> ' <table>...</table>' -> ' ' >> 'hello' -> '' >> ' hello' -> ' ' >> >> Thanks. > > Have you tried regular expressions? Something like: > > ^( )*[^ ] > > The first captured match is the number of spaces, from 0 to any > amount. Not the space between the brackets and before the closing > square bracket > You need to take into consideration that "whitespace" can be created by more than the simple "space" (ascii 32) character. A "[horizontal] tab" (ascii 9) is common, but also look at the top of php trim function documentation: <http://php.net/manual/en/function.trim.php> to see the characters that it handles as "whitespace". While "trim" does the opposite of what you're after, you could likely use the ctype_space function to accomplish your need: <http://php.net/manual/en/function.ctype-space.php> e.g., by iterating through the string until it returns "false". Also, "strpos" could be useful.