angularjs drop down showing nothing selected when loading first time [duplicate] - angularjs

Question

This question already has answers here:
How do I set default value of select box in angularjs
(7 answers)
Closed 7 years ago.
I have a drop down using angularjs but at initial loading it showing 'nothing selected' ,I want select First value default.
<select id="cbo-db-selection" ng-init="selectedlibrary=selectedlibrary[0].value" ng-model="selectedlibrary" required="required" ng-options="opt.DatabaseName as opt.DatabaseName for opt in DBLibraries">
<option style="display:none" value="">{{selectedlibrary}}</option>
</select>

Answer 1

var app = angular.module('myApp', []);
app.controller('myCtrl', function ($scope) {
$scope.users = [
{id: 1, name: 'Me'},
{id: 2, name: 'You'}
];
});
app.directive('select', function () {
return {
restrict: 'E',
require: '?ngModel',
priority: 10,
link: function postLink(scope, elem, attrs, ctrl) {
if (!ctrl) { return; }
var originalRender = ctrl.$render.bind(ctrl);
ctrl.$render = function () {
originalRender();
if (elem.val() === '?') {
ctrl.$setViewValue(undefined);
}
};
}
};
});
.error {
color: Red;
}
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.16/angular.min.js"></script>
<div ng-app="myApp" ng-controller="myCtrl" ng-form="form1">
<select ng-model="userId">
<option ng-repeat="user in users"
value="{{user.id}}">
{{user.name}}
</option>
</select>
<div class="error" ng-show="form1.select1.$invalid">Required field !</div>
<div class="error" ng-show="form1.$invalid">Invalid form !</div>
<br />
<button ng-click="userId=1;">Set valid value</button>
<button ng-click="userId=3;">Set invalid value</button>
<hr />
<pre>userId: {{userId}}</pre>
</div>