PHP function container ing...

My function container (PHP):

1.gettype($variable)

return type of variable

2.preg_match($pattern,$string)

return true/ false

3.strpos($all,$neddle)

Return the index of the first match/false

4.cal_days_in_month(201502)

return the total number of days in this month

The above introduces the PHP function container ing..., including aspects of the content. I hope it will be helpful to friends who are interested in PHP tutorials.