angularJS select下拉框检测改变

<div style="width:70px;display:inline-block;">
<form class="am-form am-form-inline" >
<div class="am-input-group am-form-icon am-form-feedback ">
<span class="am-input-group-btn">
<select ng-model="type" ng-options="t.value as t.name for t in typeOptions"
class="am-form-field am-input-sm" id="typeOption" ng-change="typeChange()"> //注：一定是typeChange(),而不是typeChange
</select>
</span>
</div>
</form>
</div>

$scope.type = '1';
$scope.typeOption = [{
name:'全部',
value:'1'
},
{
name:'今天',
value:'2'
},
{
name:'昨天',
value:'3'
},
{
name:'上一月',
value:'4'
}];$scope.typeChange = function(){
console.log('type',$scope.type);
...
}