


Why Am I Getting 'Unknown Modifier 'g' in...' Error When Using preg_match in PHP?
Encountering ""Unknown modifier 'g' in..." Error When Using preg_match in PHP?
When attempting to employ the preg_match function for regular expression matching, you may encounter an error indicating an "Unknown modifier 'g'". This issue arises when the 'g' modifier, which specifies global matching, is appended to the regular expression.
Understanding the Error
PHP does not provide the 'g' modifier for the preg_match function. Instead, the preg_match_all function should be used for global matching scenarios.
Resolution
To rectify this issue and perform global matching, simply replace preg_match with preg_match_all in your code. Your modified regular expression should look like this:
preg_match_all("/^(\w|\.|-)+?@(\w|-)+?\.\w{2,4}($|\.\w{2,4})$/im", ...)
Remember, the 'i' modifier ensures case-insensitive matching, while the 'm' modifier enables multiline string matching.
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