String manipulation

Anon

In C, you can do something like:

char str[] = "string1:string2";
char *sub;

sub = strchr (str, ':');
sub++;

To get sub to point to the string just past
the delimiter. How is this done in PHP?

Anon

I think this is what you are looking for:
http://www.php.net/manual/function.strpos.php

and
http://www.php.net/manual/function.substr.php

Basically, try this:

$str = "string1:string2";
$cloc = strpos($str, ":");
$str2 = substr($str, ++$cloc);

now, $str will contain the original string, $cloc will contain the position of the beginning of the second string, and $str2 will contain the second string. I think thats what you are looking for.

Chris King

Anon

I'm actually a little curious as to why you'd want to do this. Typically one uses tools like PHP to get away from such low-level string manipulation. But I realize that that's just what you may want to do, so if it is, feel free to disregard everything below =)

If what you want is string2, you could use explode() on the string, a la

$parts = explode(":", $string);

which, if $string is set as your example, will give you $parts[0] == "string1" and $parts[1] == "string2";

Anon

<<I think this is what you are looking for:>>


<<now, $str will contain the original string, $cloc will contain the position of the beginning of the second string, and $str2 will contain the second string. >>


I'll give that a try, thanks.

Anon

<<I'm actually a little curious as to why you'd want to do this. Typically one uses tools like PHP to get away from such low-level string manipulation. But I realize that that's just what you may want to do, so if it is, feel free to disregard everything below =) >>

I am a long-time C programmer, so I tend to think of C-style solutions first.

<<If what you want is string2, you could use explode() on the string, a la

$parts = explode(":", $string);

which, if $string is set as your example, will give you $parts[0] == "string1" and $parts[1] == "string2"; >>

There's no guarantee that ':' won't appear in the rest of the string. explode() would then break that string up, which would be undesireable. I could glue the parts back together, of course.

The big problem is that the string will actually be of the form:

field1: some stuff
field2: some other stuff
.
.
.
fieldn: final stuff

I guess I could work it morewith explode(), and break the first string on the line breaks, then process each substring

Anon

Hm, so is the problem that you want to get two strings out of one, where the two strings are separated by a colon? There's a way to do that too, using regular expressions.

ereg("(.?)🙁.)$", $data, $matches);

ought to put what's to the left of the first colon into $matches[0] (or is that [1] ... damn, too much perl-ing lately =) and what's to the right of that colon into $matches[1] (or is that [2] ? =)

Regex- munging ... loads of fun. See the tutorials on this site and others for the details.

If you have a colon-separated list in $data where the elements of the list may contain colons, presumably you've got some sort of 'escape' character that says "this colon is not a spearator", a la backslash. The relevant call to "explode" can handle this too:

$parts = explode("[^\]:", $data);

which says, roughly "split on colons that aren't preceded by a backslash".

HTH,

Anon

Hieronymous Coweld wrote:

Well, the string will be coming in from a form, so there's no guarantee that the person filling out the form would properly escape the other colons.

I think if I explode() the string first using the carriage returns, then process those substrings, I should be ok.