Html::dropDownList

Html::dropDownList is a method used in Yii framework to create a dropdown list in HTML. It is used to create a select element with options that a user can select from.

Syntax:

Html::dropDownList($name, $selection = null, $items = [], $options = [])

Parameters:

- $name: string, the name attribute of the select element.
- $selection: mixed, the selected value(s). This can be a string or an array of strings depending on whether the select element is multiple or not.
- $items: array, the options for the select element. The keys are the option values and the values are the option labels.
- $options: array, the HTML attributes for the select element. This can include attributes like class, id, style, etc.

Example:

echo Html::dropDownList('gender', null, ['M' => 'Male', 'F' => 'Female'], ['prompt' => 'Select Gender']);

This will create a dropdown list with name attribute "gender", no pre-selected value, two options "Male" and "Female" with values "M" and "F" respectively, and a prompt option "Select Gender".