Add select options dynamically to admin form in magento2

Question

I have created a model.

$fieldset->addField(
        'test1',
        'text',
        array(
            'name' => 'test1',
            'label' => __('Test 1'),
            'title' => __('Test 1'),
            /*'required' => true,*/
        )
    );

  $fieldset->addField(
        "test2",
        "select",
        [
            "label"     =>      __("Test 2"),
            "name"      =>      "test2",
            "values"    =>      [
                ["value" => 1,"label" => __("Option 1")],
                ["value" => 2,"label" => __("Option 2")],
                ["value" => 3,"label" => __("Option 3")],
                ["value" => 4,"label" => __("Option 4")],
                ["value" => 5,"label" => __("Option 5")],
            ]
        ]
    );

This is working well, but i need to add the option values dynamically, that is i need to get the result from one of the custom table and add them as values.

my custom table have the record like below.

  table custom_table;

  id   options

  1   Option 1

  2   Option 2

  3   Option 3

  4   Option 4

  5   Option 5

How to read this table and add the result as value for my admin form field there.

Can anyone look into this and update me your ideas please.

Thanks

Answer 1

This is not really a recommended way but I think you can write a custom Mysql Query (Without Using Model).

You can try like this:

$objectManager = \Magento\Framework\App\ObjectManager::getInstance(); 
$resource = $objectManager->get('Magento\Framework\App\ResourceConnection');
$connection = $resource->getConnection();
$tableName = $resource->getTableName('custom_table'); 

//Select Data from custom_table
$sql = "Select * FROM " . $tableName;
$result = $connection->fetchAll($sql);  

And you can loop the result in your select field options like this:

foreach($result as $key => $option){
      $options[] = ["value" => $key,"label" => __($option)],
}

$fieldset->addField(
     "test2",
     "select",
     [
         "label"     =>      __("Test 2"),
         "name"      =>      "test2",
         "values"    =>    [$options]
     ]
 );

Adding here: Fetch database custom table using custom model and Resourcemodel

Answer 2

This is the correct answer

foreach($result as $key => $option){
      $options[] = ["value" => $key,"label" => __($option)],
}

    $fieldset->addField(
         "test2",
         "select",
         [
             "label"     =>      __("Test 2"),
             "name"      =>      "test2",
             "values"    =>    $options
         ]
     );