How to push array values via php function?

I have an empty array that I am trying to push a value to via a simple php function. The problem is that within each iteration the values are not being retained. Here is an example:

我有一个空数组,我试图通过一个简单的PHP函数推送值。问题是在每次迭代中都没有保留这些值。这是一个例子:

function addColors($arrayValues, $arrayToUpdate){
    $arrayToUpdate[]=$arrayValues;
}

$colors = array();
$newColors= array("red", "blue", "yellow");

foreach($newColors as $newColor){
    addColors($newColor, $colors);
}

echo "<pre>".print_r($colors, true)."</pre>";

This will just print an empty array. Whereas what I would like to see are the values being added to the $colors array. Any suggestions?

这只会打印一个空数组。而我希望看到的是添加到$ colors数组的值。有什么建议么?

1 个解决方案

#1

You either need to return the new array and assign the returned array in the loop:

您需要返回新数组并在循环中分配返回的数组:

function addColors($arrayValues, $arrayToUpdate){
    $arrayToUpdate[]=$arrayValues;
    return $arrayToUpdate;
}

foreach($newColors as $newColor){
    $colors = addColors($newColor, $colors);
}

Or to do it the way you have it, pass the variable that needs to be updated as a reference; notice the &. This is my recommendation:

或者按照你的方式去做,传递需要更新的变量作为参考;注意&。这是我的建议:

function addColors($arrayValues, &$arrayToUpdate){
    $arrayToUpdate[]=$arrayValues;
}

foreach($newColors as $newColor){
    addColors($newColor, $colors);
}

Though in this simple example I wouldn't use a function:

虽然在这个简单的例子中我不会使用函数:

foreach($newColors as $newColor){
    $colors[] = $newColor;
}

Also, there is already a function that does this, though the arguments are in a different order:

此外,虽然参数的顺序不同,但已有一个函数可以执行此操作:

array_push($colors, $newColor);

Even simpler without the loop:

没有循环就更简单了:

$colors = array_merge($colors, $newColors);

#1