angular checkbox

Error: ngModel:constexpr Non-Constant Expression

1.3版本
<input type="checkbox" ng-model="test3" ng-true-value="yes" ng-false-value="no">

1.5版本
<input type="checkbox" ng-model="test3" ng-true-value="'yes'" ng-false-value="'no'">

兼容
<input type="checkbox" ng-model="test3" ng-true-value="1" ng-false-value="0">

$scope.test3 = '1' 需要是字符串