足球是這樣踢
PHP: isset - Manual - PHP: Hypertext Preprocessor兒子看好了,足球是這樣踢的 Determine if a variable is set and is not NULL. If a variable has been unset with unset(), it will no longer be set. isset() will return FALSE if testing a variable that has been set to NULL. Also note that a null character ("\0") is not equivalent to...
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