Angular 4 ng-show

I need to hide and show a textbox based on the value selected in the drop-down.

This is already done in Angular 1, but how to do it in Angular 4.

<div ng-app ng-controller="Controller">
    <select ng-model="myDropDown">
          <option value="one">One</option>
          <option value="two">Two</option>
          <option value="three">Three</option>
    </select>

    <input ng-show="myDropDown=='two'" type="text">
</div>


function Controller ($scope) {
    $scope.myDropDown = 'one';
}

Fiddle in Angular 1

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Link to original article：https://stackoverflow.com/questions/50679774/angular-4-ng-show