在比較運算符（>、<、>=、<=、==、===、!=、<>、!==）、賦值運算符（=）、數學運算符（+、-、*、/、%）、位運算符（&、|、^、~、>>、<<）、邏輯運算符（!、&&、||）、冒號(:)、問號（?）、字符串連接運算符（.）、字符串連接賦值運算符(.=）前后，以及左括號（(）前（函數調用例外）、逗號（,）后請使用空格進行間隔。 例如: /* These are all wrong. */ $i=0; /* These are all right. */ $i = 0; /* These are all wrong. */ if($i<7) ... /* These are all right. */ if ($i < 7) ... /* These are all wrong. */ if ( ($i < 7)&&($j > 8) ) ... /* These are all right. */ if (($i < 7) && ($j > 8)) ... /* These are all wrong. */ do_stuff($i,"foo",$b); /* These are all right. */ do_stuff($i, "foo", $b); /* These are all wrong. */ for($i=0; $i<$size; $i++) ... /* These are all right. */ for ($i = 0;$i < $size;$i++) ... /* These are all wrong. */ $i=($j < $size)?0:1; /* These are all rightg. */ $i = ($j < $size)?? 0?: 1;