dongnvwang8591 2011-06-20 12:23
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PHP如果速记

I would like to a simple if shorthand that check if an array has a particular key and if so unset it.

$test = array("hi" => "123");
isset($test["hi"]) ? unset($test["hi"]);

Why does this give a parse error? What is the correct syntax.

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  • dpr77335 2011-06-20 12:27
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    Because it is a ternary operator. This code:

    $a = ($condition)? $b : $c;
    

    is equivalent to:

    if($condition) $a = $b;
    else $a = $c;
    

    For what you ask, there is no need for a check, you can simply unset() the array element without first checking it, and it would give no error messages:

    unset($test["hi"]);
    
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