确认密码自定义指令在Angular中不起作用

我尝试在角度视图中实施确认密码验证。写新

app.js中的指令

并添加compare-to确认密码文本框

<div class="form-group">
        <label class="control-label col-sm-2" for="pwd">Password:</label>
        <div class="col-sm-10">
            <input type="password"
                   class="form-control"
                   placeholder="Enter password"
                   ng-model="Password"
                   ng-minlength="5">

            <span class="validationMessage" ng-show="frm.password.$dirty && frm.password.$error.required">Required!</span>
            <span class="validationMessage" ng-show="frm.password.$dirty && frm.password.$error.minlength">Min length 5!</span>
        </div>
    </div>
    <div class="form-group">
        <label class="control-label col-sm-2" for="pwd">Confirm Password:</label>
        <div class="col-sm-10">
            <input type="password"
                   class="form-control"
                   ng-model="ConfirmPassword"
                   required
                   compare-to="Password"
                   placeholder="Enter Confirm password">

            <span class="validationMessage" ng-show="frm.ConfirmPassword.$error">Required!</span>
        </div>
    </div>

但是确认密码没有显示任何验证。并显示错误消息：无法在chrome中设置未定义的属性“ compareTo”。