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注意PHP对字符串的递增运算，需要的朋友可以参考下。 有同学问了一个问题: <?php for($i = 'A'; $i <= 'Z'; $i++) { echo $i; } //输出是啥?
ABCDEFGHIJKLMNOPQRSTUVWXYZAAABACADAEAFAGAHAIAJAKALAMANAOAPAQARAS…….
PHP follows Perl's convention when dealing with arithmetic operations on character variables and not C's. For example, in Perl ‘Z'+1 turns into ‘AA', while in C ‘Z'+1 turns into ‘[‘ ( ord(‘Z') == 90, ord(‘[‘) == 91 ). Note that character variables can be incremented but not decremented and even so only plain ASCII characters (a-z and A-Z) are supported.
$name = "laruence"; ++$name; //将会是"laruencf"
$name = "laruence"; --$name; //没有影响, 还是"laruence"
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