dougong2005 2016-11-10 17:01
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在if语句中定义和检查变量

I am wanting to see if there is a simplified way of doing an if statement that is checking multiple conditions, where it uses data from the same function.

if($class->function($id) && $class->function($id)['key'] > 0)
{ 
    //Do something...
}

The issue here is we're making 2 database calls that retrieve the same data. One obvious solution is doing the following:

$classVariable = $class->function($id);
if($classVariable && $classVariable['key'] > 0)
{
    //Do something...
}

My question specifically is, can I achieve the same effect all inside the if statement? For example(this will not work):

if($classVariable = $class->function($id) && $classVariable['key'] > 0
{
    //Do something...
}

Is this possible, and is there a preferred way of doing this? It seems to me that defining and using it in the same statement would be cleaner code...

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1条回答 默认 最新

  • dragon8899 2016-11-10 17:10
    关注

    As Niet said, using parentheses () around the $classVariable assignment and things should work.

    (I just wanted to post this as an answer rather than a comment so the question gets resolved, sorry Niet)

    Edited by OP to show answer in code...

    if(($classVariable = $class->function($id)) && $classVariable['key'] > 0)
    {
        //Do something...
    }
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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