Select dropdown as selected using value in ng-options AngularJS

Question

I am trying to set China as selected country but somehow it is only setting China in dropdown if I am doing like - $scope.countrySelected = $scope.countryList[5];

Let me know if it is possible to set value by text only as through Service I am getting China as a text only which I need to match.

HTML Code -

<select 
 ng-options="country.c_name for country in countryList track by country.c_id" 
 ng-model="countrySelected">
</select>

SCRIPT CODE -

var myApp = angular.module('myApp', []);

myApp.controller('mainCtrl', function($scope){
  $scope.countryList = [
    {c_id: 1, c_name: 'Iran'},
    {c_id: 2, c_name: 'Iraq'},
    {c_id: 3, c_name: 'Pakistan'},
    {c_id: 4, c_name: 'Somalia'},
    {c_id: 5, c_name: 'Libya'},
    {c_id: 6, c_name: 'China'},
    {c_id: 7, c_name: 'Palestine'}
  ];

  $scope.countrySelected = 'China';
})

Working Plnkr - http://plnkr.co/edit/6qSvuuOtJHVSoNWah0KR?p=preview

Answer 1

You can use filter method which accepts as parameter a callback function.

The filter() method creates a new array with all elements that pass the test implemented by the provided function.

$scope.countrySelected = $scope.countryList.filter(function(item){
     return item.c_name=='China';
})[0];

Working Plnkr

Also, another method is to use find method.

$scope.countrySelected = $scope.countryList.find(function(item){
     return item.c_name=='China';
});

For older version of browser which are incompatible with these methods you can implement your own filter method.

Array.prototype.filter = function(func, thisArg) {
   'use strict';
   if ( ! ((typeof func === 'Function') && this) )
      throw new TypeError();

   var len = this.length >>> 0,
   res = new Array(len), // preallocate array
   c = 0, i = -1;
   if (thisArg === undefined)
      while (++i !== len)
        // checks to see if the key was set
        if (i in this)
           if (func(t[i], i, t))
             res[c++] = t[i];
   else
      while (++i !== len)
         // checks to see if the key was set
         if (i in this)
            if (func.call(thisArg, t[i], i, t))
              res[c++] = t[i];
   res.length = c; // shrink down array to proper size
   return res;
};

Source: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter