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问题:
I know, this question has been asked, but unfortunately, there are no answers how to solve this problem.
This appears in my logfiles:
PHP message: PHP Warning: strpos(): Offset not contained in string in ... on line 479
Unfortunately, I can not understand what causes this problem and how to fix it. I tested this function many times (with large $text, with short $text, with $spam words and without $spam words) but I never get this error. So, what kind of texts my users submit that cause this error?
if (strposab($text, $spam, 1)) { echo "Email addresses and URLs not allowed here"; die; } $spam = array('http','www','hotmail','yahoo','gmail','msn'); function strposab($haystack, $needles=array(), $offset=0) { $chr = array(); foreach($needles as $needle) { $res = strpos($haystack, $needle, $offset); if ($res !== false) $chr[$needle] = $res; } if(empty($chr)) return false; return min($chr); }
Second question:
For some reason this function does not filter the first word of the string. For example in this string function does not find word "hotmail":
$text = 'hotmail test test test test';
but in this string it finds word " hotmail":
$text = 'test hotmail test test test test';
回答1:
To the first question:
Most likely at one point you're passing an empty string to your function. Offset in the strpos call indicates from which character it should start searching for $needle. It's 0-based, so if you want to start from the absolute beginning, you either set it to 0 or omit it (it defaults to 0.)
To the second question:
As mentioned before, the offset is 0-based, so if $needle you're searching for is exactly in the beginning of $haystack, it cannot be found if $offset is 1. With $offset = 1 it would be as if you're searching in a string that looks like this: 'otmail test test test test'.
One more thing:
I suggest you should use stripos, not strpos for your purposes, as it is case-insensitive and will also find words with uppercase letters, if it's something you might need.
回答2:
The offset value is higher than the length of the string to search in.
回答3:
To answer your second question - you have two issues in your code. Assuming your text string is:
$text = 'hotmail test test test test';
..and your if statement is
if (strposab($text, $spam, 1))
First, you're starting at offset 1, while the word "hotmail" is at position 0. So by specifying an offset of 1, you're checking against the String:
otmail test test test test
...and not
hotmail test test test test
Second of all, with "hotmail" being at position 0, your strposab() function will return a value of int(0), which is a non-Boolean value that when used in a Boolean expression evaluates to FALSE. Therefore, you need to use the !== operator in order to avoid type juggling. So the correct if statement to use will be:
if (strposab($text, $spam, 0) !== false)
