notice:undefined offset:1 in d:\\wwwroot\\wr\\askseo\\404.php on line 5

notice:undefined offset:1 in D:\wwwroot\wr\askseo\404.php on line 5

This problem is very often in the array, the program is able to run correctly, but on the screen there will always be such a hint: notice:undefined offset: ... The internet is commonly used to suppress the display of the method, that is, change the php.ini file error_repoting parameter is "Eall & Notice", so that the screen can be displayed normally.
The problem is solved, but I can't get through offset: what the next number (such as notice:undefined offset:4 ...) means. Also, the syntax of the sentence is clearly correct and why there is a warning. Calmly thinking for several times and trying every possible
Finally found the answer. Offset: The next number is an error in the array subscript, is generally beyond the range of the array, such as the definition of the array $a[] There are 10 of the number of $a[10, if there is an error (notice:undefined offset:10 ...), Because the subscript of the array starts at 0, so the subscript of this array can only be 0~9. So in the case of this kind of problem, do not rush to suppress the display of the method (more simply can be in the front of the current file with a "error_reporting (offset: the next number); Be sure to pay attention to the array subscript you use, think carefully, the problem will be solved quickly! It is possible to send a unset array and then try to read its contents, as in the PHP manual: