继续获取“数组到字符串转换”尝试运行连接方法时出错

Question

So I'm working on a problem where I need to convert an array of values into a string so that it can be displayed for an excel document. But I keep on getting an "Array to string conversion" error when I try to run the export. The code is

$counties = "";
if(isset($forms->form_info['county'])){
  for($i = 0; $i < count($forms->form_info['county']); $i++){
    if(is_int($i / 10) && $i != 0){
      $counties .= $forms->form_info['county'][$i] . ",
";
    } elseif($i == (count($forms->form_info['county']) - 1)) {
      // Keep getting the error on the line below
      $counties .= $forms->form_info['county'][$i] . " ";
    } else {
      $counties .= $forms->form_info['county'][$i] . ", ";
    }
  }
}

I've done a dd of a gettype on counties as well as the form element I'm trying to use, and both appeared as strings, so I'm lost on where the supposed array that's being converted is. I've tried making $form->form_info['county'][$i] into its own variable and concatenating it to the counties variable but received the same issue.

The result of dd($forms->form_info['county'][$i]); is

"Bernalillo County"

The result of dd($forms->form_info['county']); is

array:1 [▼
   0 => "Bernalillo County"
]

The result of a dd(var_dump($forms->form_info['county'][$i])); is

string(17) "Bernalillo County"
null

And here is the direct screenshot of the issue

Answer 1

Obviously the data is not what you expect, but this code is very verbose for what you're trying to do: separate the array values with commas, putting a line break after every tenth element. We can do that easily with use of array_chunk.

<?php
$data = str_split("abcdefghijklmnopqrstuvwxyz");
$output = "";

foreach(array_chunk($data, 10) as $v) {
    $output .= implode(", ", $v) . ",
";
}
// get rid of that final comma space
echo substr($output, 0, -2);

Output:

a, b, c, d, e, f, g, h, i, j,
k, l, m, n, o, p, q, r, s, t,
u, v, w, x, y, z

Adapting to your code:

$counties = "";
if(isset($forms->form_info['county'])){
    foreach(array_chunk($forms->form_info['county'], 10) as $v) {
        $counties .= implode(", ", $v) . ",
";
    }
    $counties = substr($counties, 0, -2);
}