Regular expressions represent regular _ regular expressions at the beginning of a specified string

Although the code is not much, but simple and clear

Copy Code code as follows:

Preg_match ('/^ (?!) String)/', ' aa ') = = True

This is used to verify that a string does not start with a ' string '.
In Perl or in the language of regular expressions that support Perl (such as PHP), you can do this with a front-view declaration:

Copy Code code as follows:

Preg_match ('/.* (?!) \.txt) $/', ' AA ')

It means matching all names that do not end with. txt.

The above meaning is not very familiar, you can refer to the following the regular expression of the basic parameters of the description, see through.
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