Php interview questions

1. calculate the relative path functiongetpathinfo ($ a, $ B) {$ a2array = explode (& amp; #39;/& amp; #39;, $ ); $ b2array = explode (& amp; #39;/& amp; #39;, $ B); $ pathinfo

1. calculate relative paths

 

Function getpathinfo ($ a, $ B) {$ a2array = explode ('/', $ a); $ b2array = explode ('/', $ B ); $ pathinfo = ''; for ($ I = 1; $ I <= count ($ b2array)-2; $ I ++) {$ pathinfo. = $ a2array [$ I] = $ b2array [$ I]? '.. /': $ B2array [$ I]. '/';} print_R ($ pathinfo);} // calculate c. php Vs. e. the relative path of php should be .. /.. /12/34 $ a = '/a/B/c/d/e. php '; $ B ='/a/B/12/34/c. php'; getpathinfo ($ a, $ B);?> Function getpathinfo ($ a, $ B) {$ a2array = explode ('/', $ a); $ b2array = explode ('/', $ B ); $ pathinfo = ''; for ($ I = 1; $ I <= count ($ b2array)-2; $ I ++) {$ pathinfo. = $ a2array [$ I] = $ b2array [$ I]? '.. /': $ B2array [$ I]. '/';} print_R ($ pathinfo);} // calculate c. php Vs. e. the relative path of php should be .. /.. /12/34 $ a = '/a/B/c/d/e. php '; $ B ='/a/B/12/34/c. php'; getpathinfo ($ a, $ B);?>

2. paging principle

SELECT * FROM table ...... The start position of the limit operation. paging formula: (current Page number-1) X number of entries per Page. Select * from table limit ($ Page-1) * $ PageSize, $ PageSize SELECT * FROM table ...... The start position of the limit operation. The paging formula is as follows: (current Page number-1) X number of entries per Page, number of entries per Page Select * from table limit ($ Page-1) * $ PageSize, $ PageSize

3. determine whether it is post or get.

 $_SERVER['REQUEST_METHOD'] == 'POST' $_SERVER['REQUEST_METHOD'] == 'POST'