php中switch语句用法详解

=90 && $score<=100: echo "优
"; break; case $score>=80 && $score<90: echo "良
"; break; case $score>=70 && $score<80: echo "中
"; break; case $score>=60 && $score<70: echo "及格
"; break; case $score>=0 && $score<60: echo "不及格
"; break; default: echo"成绩输入错误
"; } ?>

'.'成功退出····'; echo '

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'; //情况二：数值匹配的时候自动转换成字符 $a=1; switch($a){ case '1': echo 'hello2'; break; default: echo 'sorry none is the same!'; break; } echo '
'.'成功退出····'; echo '

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'; //情况三：字符匹配的时候自动转换成数值 $a='1'; switch($a){ case 1: echo 'hello3'; break; default: echo 'sorry none is the same!'; break; } echo '
'.'成功退出····'; echo '

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'; //情况四：字串匹配的时候自动转换成数值 $a="1"; switch($a){ case 1: echo 'hello4'; break; default: echo 'sorry none is the same!'; break; } echo '
'.'成功退出····'; echo '

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'; //情况五：float也可以匹配 $a=1.1; switch($a){ case 1.1: echo 'hello5'; break; default: echo 'sorry none is the same!'; break; } echo '
'.'成功退出····'; echo '

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'; //情况六：非0是true $a=true; switch($a){ case 1: echo 'hello6'; break; case true: echo 'hello61'; break; default: echo 'sorry none is the same!'; break; } echo '
'.'成功退出····'; echo '

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'; //情况七：能匹配boolean $a=true; switch($a){ case true: echo 'hello7'; break; case 2: echo 'hello71'; break; default: echo 'sorry none is the same!'; break; } echo '
'.'成功退出····'; echo '

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'; //情况八：能匹配null $a=null; switch($a){ case 2://'' "" false 0 都能进入 echo 'hello8'; break; case null: echo 'hello81'; break; default: echo 'sorry none is the same!'; break; } echo '
'.'成功退出····'; echo '

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'; //情况九：退出顺序 $a=5; switch($a){ case 1: echo 'hello6'; break; case 2: echo '我是2号出口'; break; case 5: echo '我是5号出口'; //break; case true: echo 'hello61'; break; default: echo 'sorry none is the same!'; break; } echo '
'.'成功退出····'; echo '

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'; //情况十：退出顺序 $a=50; switch($a){ default: echo 'sorry none is the same!'; //break; case 50: echo 'hello6'; //break; case 2: echo '我是2号出口'; break; case 5: echo '我是5号出口'; //break; case 6: echo 'hello61'; break; } echo '
'.'成功退出····'; echo '

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'; ?>