PHP replace preceding substrings of some other substring

Question

Let's say I have this string:

$myString = 'aaa = b AND cc = dd OR e = ff_%_g AND hh = iii AND j = k_%_lll ...'

I want to check if the substring '_%_' is present, and in that case, I want to replace the previous (and only the previous) '=' by a 'LIKE'.

Namely, I want this:

$myString = 'aaa = b AND cc = dd OR e LIKE ff_%_g AND hh = iii AND j LIKE k_%_lll ...'

I know how to replace all the '=' using strpos() and substr_replace(), but I need to replace only those that precede a '_%_'

Any help, please?

hek2mgl · Accepted Answer · 2014-03-11 13:36:58Z

2

Here you go:

$myString = preg_replace("/=([^=]*_%_[^ ]*)/", "LIKE $1", $myString);

hek2mgl

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answered Mar 11, 2014 at 13:33

Sabuj Hassan

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3 Comments

Thanks mate! Don't know why, but I think I'll never get along well with regexps :)

@hek2mgl, can you explain your edit? Shouldn't it work fine without that?

@MikO No, without the [^ ]* it would make foo_%_ out of foo_%_bar. The answer was basically good, so I decided to edit this.