PHP - 使用数字索引获取数组值
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/6396294/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
PHP - Get array value with a numeric index
提问by thom
I have an array like:
我有一个像这样的数组：
$array = array('foo' => 'bar', 33 => 'bin', 'lorem' => 'ipsum');
echo native_function($array, 0); // bar
echo native_function($array, 1); // bin
echo native_function($array, 2); // ipsum
So, this native function would return a value based on a numeric index (second arg), ignoring assoc keys, looking for the real position in array.
因此，这个本机函数将返回一个基于数字索引（第二个参数）的值，忽略关联键，寻找数组中的实际位置。
Are there any native function to do that in PHP or should I write it? Thanks
是否有任何本机函数可以在 PHP 中执行此操作，还是应该编写它？谢谢
回答by genesis
$array = array('foo' => 'bar', 33 => 'bin', 'lorem' => 'ipsum');
$array = array_values($array);
echo $array[0]; //bar
echo $array[1]; //bin
echo $array[2]; //ipsum
回答by John Carter
array_values()will do pretty much what you want:
array_values()几乎可以做你想做的事：
$numeric_indexed_array = array_values($your_array);
// $numeric_indexed_array = array('bar', 'bin', 'ipsum');
print($numeric_indexed_array[0]); // bar
回答by and.ryx
I am proposing my idea about it against any disadvantages array_values( )function, because I think that is not a direct get function.
In this way it have to create a copy of the values numerically indexed array and then access. If PHP does not hide a method that automatically translates an integer in the position of the desired element, maybe a slightly better solution might consist of a function that runs the array with a counter until it leads to the desired position, then return the element reached.
我针对任何缺点array_values( )函数提出了我的想法，因为我认为这不是一个直接的 get 函数。通过这种方式，它必须创建数值索引数组的副本，然后访问。如果 PHP 没有隐藏自动将整数转换为所需元素位置的方法，也许更好的解决方案可能包括一个函数，该函数使用计数器运行数组，直到到达所需位置，然后返回到达的元素.
So the work would be optimized for very large array of sizes, since the algorithm would be best performing indices for small, stopping immediately. In the solution highlighted of array_values( ), however, it has to do with a cycle flowing through the whole array, even if, for e.g., I have to access $ array [1].
因此，该工作将针对非常大的数组大小进行优化，因为该算法对于小型索引的性能最佳，并立即停止。array_values( )然而，在突出显示的 解决方案中，它与流经整个数组的循环有关，即使例如，我必须访问 $array [1]。
function array_get_by_index($index, $array) {
$i=0;
foreach ($array as $value) {
if($i==$index) {
return $value;
}
$i++;
}
// may be $index exceedes size of $array. In this case NULL is returned.
return NULL;
}
回答by netcoder
Yes, for scalar values, a combination of implodeand array_slicewill do:
是的，对于标量值，implode和array_slice的组合可以：
$bar = implode(array_slice($array, 0, 1));
$bin = implode(array_slice($array, 1, 1));
$ipsum = implode(array_slice($array, 2, 1));
Or mix it up with array_valuesand list(thanks @nikic) so that it works with all types of values:
或者将它与array_values和list（感谢@nikic）混合使用，以便它适用于所有类型的值：
list($bar) = array_values(array_slice($array, 0, 1));
