dongyan1936 2014-10-16 08:49
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if语句中的布尔条件

I want to double check something about multiple conditions in a boolean if statement in PHP. Given that I write:

if(!empty($_POST) && !isset($_POST['report_btn'])) {...}

can this be re-written as

if(! ( empty($_POST) && isset($_POST['report_btn']) ) ) {...}

I'm wanting to remove one of the exclamation marks to see if I can make the code a bit tidier. The logic is to see if I can execute the code if POST data has been sent to a page but the 'report_btn' value is not set.

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  • drmeu26880 2014-10-16 08:59
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    No, You can not write the above condition as below condition:

    Reason:

    for:

    if(! ( empty($_POST) && isset($_POST['report_btn']) ) ) {...}
    

    the result matrix will:

    first_statement second_statement result
       true            true          false
       true            false         true
       false           true          true
       false           false         true
    

    And for the below

    if(!empty($_POST) && !isset($_POST['report_btn'])) {...}
    

    The result matrix will be:

    first_statement second_statement result
       true            true          false
       true            false         false
       false           true          false
       false           false         true
    

    It means both code are not similar.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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