在PHP中禁用“添加选定选项”

在PHP中，我有一个带有下拉字段的表单，其中包含以下数组：

$field["options"] = array(
     array("value" => "Chişinău", "text" => "Chişinău", "depth" => 0),
     array("value" => "Bălţi", "text" => "Bălţi", "depth" => 0),
     array("value" => "Comrat", "text" => "Comrat", "depth" => 0),
     ...
     array("value" => "Ungheni", "text" => "Ungheni", "depth" => 0)
);

如何添加作为第一个选项的

选择一个
？
尝试
数组（“值”=>“Chişinău”，“文本”=>“Chişinău”，“深度”=>0，“选中”=>“选中”，“禁用”=>“禁用”），
？
$field["options"] = array(
    array("value" => " ", "text" => "Choose one", "depth" => 0, "selected" => "selected", "disabled" => "disabled"),
    //...rest other option code
);