duandu2980 2012-12-04 15:35
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在条件中使用变量值

I have a condition stored in a variable $condition = "1==1" and I want to use the value of the variable in a conditional statement.

if($condition) { //$condition should be parsed as 1==1
    return true;
}

Is this possible? I've tried using var_export but apparently that doesn't work.

if(var_export($condition)) {
    return true;
}

Any help will be greatly appreciated!

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  • dongquxiao8545 2012-12-04 16:03
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    After some discussion in the comments above we found out, that the condition itself is not the problem, but how it is passed to the function

    conditional_func($var . " == 'test'", $result);
    

    We realized, that it is not required to pass the first parameter as a string, but can use a boolean directly, thus we don't need to evaluate the string at all.

    conditional_func($var == 'test', $result);
    

    As a sidenote: @BryanMoyles answer is right regarding the question, but remember, that eval() is evil (you can't think of any pitfall, that may occur) and on the other hand there are only some very less quite esoteric usecases, where you can't use another approach.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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