如何将未定义的var传递给没有E_NOTICE错误的函数? [英] How do I pass undefined vars to functions without E_NOTICE errors?

问题描述

确实是一个非常简单的问题，如何将未定义的var传递给没有E_NOTICE错误的函数?

Pretty simple question really, how do I pass undefined vars to functions without E_NOTICE errors?

将未定义的变量传递给isset()之类的函数时，不会引发任何错误，但是将其发送到您自己的函数中，您会得到一个通知:未定义的偏移量:等等.

When passing undefined variables to functions such as isset(), no error is raised, but send the same to your own function and you'll get a Notice: Undefined offset: etc.

我已经想到了今天要这样做的几个原因，但是我当前的功能几乎是isset的克隆，除了它将检查是否设置了 any 的args，而不是像isset( a，b，c).

I have thought of a few reasons to want this today, but my current function is almost a clone of isset except it will check if any of the args are set, rather than all like isset(a,b,c) does.

function anyset()
{
    $argc = func_num_args();
    $argv = func_get_args();
    for ($i = 0; $i < $argc; $i++) 
        if (isset($argv[$i])) return true;
    else return false;
}

现在，例如，我有一个[x] [y]的2d巨型数组，值将随机放置在其中.我需要检查随机坐标是否包含下一个"(x-1，y-1至x + 1，y + 1)等.

Now, I have for example a giant 2d array of [x][y], into which values will be placed at random. I need to check the randomized co-ords contains anything "next" to it (x-1,y-1 to x+1,y+1) etc.

我不想做一个20,000,000的循环并初始化每个变量.我只想发送9个变量，并检查是否已设置.

I do not want to do a loop of 20,000,000 and initialise each variable. I just want to send 9 vars and check if any are already set.

while (anyset($items[$x-1][$y-1],$items[$x][$y-1],$items[$x+1][$y-1],
              $items[$x-1][$y],$items[$x][$y],$items[$x+1][$y],
              $items[$x-1][$y+1],$items[$x][$y+1],$items[$x+1][$y+1]));

像这样.

我可以做isset(x)|| isset(x)|| isset(x)，但是看起来不太好.

I could just do isset(x) || isset(x) || isset(x) but that doesn't look very nice.

有没有办法允许未定义的变量传递给我的函数而不会引发错误?

对采用简单选项不感兴趣；)

Not interested in taking the easy option ;)

感谢阅读！

\ o

更新:2012年4月12日，21:03 看起来似乎没有特殊功能允许发生这种情况.因此，要么像anyset(@ $ array [0]，@ $ array [1])这样传递，要么将所有东西包装成一千个isset，像这样:

Update: 12 April 2012, 21:03 Looks like there is no special feature allowing this to happen. So either pass like anyset(@$array[0], @$array[1]) etc, or just wrap everything in a thousand issets like so:

while (isset($items[$x-1][$y-1]) || isset($items[$x][$y-1]) || isset($items[$x+1][$y-1]) || 
       isset($items[$x-1][$y])   || isset($items[$x][$y])   || isset($items[$x+1][$y]) || 
       isset($items[$x-1][$y+1]) || isset($items[$x][$y+1]) || isset($items[$x+1][$y+1]));

希望这对以后的人有帮助！

Hope this helps someone else in the future!

推荐答案

您有三个选择:

• 使用isset正确处理逻辑(isset($ x)|| isset($ y)|| isset($ z))
• 将所有内容包装在isset()中，然后让您的函数检查是否有任何论点是正确的(有点类似)
• 使用@来抑制错误(也很容易)

@的示例为:

function a($a) { } a(@$x);

您应该记住，尽管存在某些原因是存在这些注意事项.我避免错误抑制.对我来说似乎很客气.我只是将所有内容正确包装在isset()中.冗长得多，但我认为还是更正确.

You should remember though that notices exist for a reason. I avoid error suppressing. It seems hacky to me. I would just properly wrap everything in isset(). It's a lot more verbose, but also, in my opinion anyway, more correct.

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