Angularjs select value is undefined

linyuanxie picture linyuanxie · Feb 24, 2015 · Viewed 21.1k times · Source

Now I am trying to get the value from select dropdown, but it return undefined. The thing is in html level it works as expect, Here is my code:

<div class='subcontent'>            
  <input id="me" type="radio" class='choosemethod' ng-model="paymentmethod" value="Y"><label for="me" class='choosemethod'>Me</label>
  <input id="company" type="radio"  ng-model="paymentmethod" value="N" class='choosemethod'><label for="company" class='choosemethod'>My Company</label><br/>
  <span class='helptext'>Who makes payments to this account?</span><span class='help' style='margin-left:20px;width:20px;height:20px;'>help</span>
</div>

<div class='paymentmethods subcontent' ng-switch on="paymentmethod">
  <select ng-model='selectedmethod' ng-init="selectedmethod=Memethods[0]" id='methods' ng-switch-when='Y'>
    <option ng-repeat="method in Memethods" value="{{method}}">{{method}}</option>
  </select>

  <select ng-model='selectedmethod' ng-init="selectedmethod=companies[0]" ng-switch-when='N' style='float:left'>
    <option ng-repeat='companyoption in companies' value="{{companyoption}}">{{companyoption}}</option>
  </select>

  <div class='clear'></div>
  <label for ='methods'>Payment Method</label><span class='help' style='margin-left:20px;width:20px;height:20px;'>help</span>
</div>

In js:

$scope.Memethods = ['Same as Card/Account Name','American Express','American Express Corp','Cash','Checking','MasterCard','My Visa','VISA'];
$scope.companies = ['Company Paid','MyAMEX'];

it shows fine in page, but when I try to get the value, it shows undefined. any idea?

Answer

Joe Enzminger picture Joe Enzminger · Feb 24, 2015

This is the classic "angular dot notation" issue.

Here is a working example

Basically, ng-switch creates a new scope, so when the select sets the selectedmethod property, it is doing so on the new scope, not the controller scope as you are expecting. One solution is to create a parent object for your model.

angular.module('app',[])
.controller('main', function($scope){
  $scope.selection = {};
  $scope.Memethods = ['Same as Card/Account Name','American Express','American Express Corp','Cash','Checking','MasterCard','My Visa','VISA'];
  $scope.companies = ['Company Paid','MyAMEX'];
})

and note how it's referenced differently in the html:

<select ng-model='selection.selectedmethod' ng-init="selection.selectedmethod=companies[0]" ng-switch-when='N' style='float:left'>
  <option ng-repeat='companyoption in companies' value="{{companyoption}}">{{companyoption}}</option>
</select>

A different (maybe better) way would be to use the "ControllerAs" syntax, which has the effect of doing this for you.

angular.module('app',[])
    .controller('main', function($scope){

      this.Memethods = ['Same as Card/Account Name','American Express','American Express Corp','Cash','Checking','MasterCard','My Visa','VISA'];
      this.companies = ['Company Paid','MyAMEX'];
    })

<body ng-app="app" ng-controller="main as main">
  <div class='subcontent'>
    <input id="me" type="radio" class='choosemethod' ng-model="paymentmethod" value="Y">
    <label for="me" class='choosemethod'>Me</label>
    <input id="company" type="radio" ng-model="paymentmethod" value="N" class='choosemethod'>
    <label for="company" class='choosemethod'>My Company</label>
    <br/>
    <span class='helptext'>Who makes payments to this account?</span><span class='help' style='margin-left:20px;width:20px;height:20px;'>help</span>
  </div>

  <div class='paymentmethods subcontent' ng-switch on="paymentmethod">
    <select ng-model='main.selectedmethod' ng-init="main.selectedmethod=main.Memethods[0]" id='methods' ng-switch-when='Y'>
      <option ng-repeat="method in main.Memethods" value="{{method}}">{{method}}</option>
    </select>

    <select ng-model='main.selectedmethod' ng-init="main.selectedmethod=main.companies[0]" ng-switch-when='N' style='float:left'>
      <option ng-repeat='companyoption in main.companies' value="{{companyoption}}">{{companyoption}}</option>
    </select>

    <div class='clear'></div>
    <label for='methods'>Payment Method</label><span class='help' style='margin-left:20px;width:20px;height:20px;'>help</span>

  </div>
  <div>{{main.selectedmethod}}</div>
</body>