Question

我的表单中有一个文件上传控件。我正在使用Angular JS。当我输入required属性来验证文件是否被选中时，它无效。

<input id="userUpload" name="userUpload" required type="file" accept="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" />

<button type="submit" class="btn btn-primary"><i class="icon-white icon-ok"></i>&nbsp;Ok</button>

你能否说明为什么要求不起作用？

Answer 1

ngModelController基于require等属性在Angular中进行验证。但是，目前使用ng-model服务不支持input type="file"。为了使它工作，你可以创建一个这样的指令：

app.directive('validFile',function(){
  return {
    require:'ngModel',
    link:function(scope,el,attrs,ngModel){
      //change event is fired when file is selected
      el.bind('change',function(){
        scope.$apply(function(){
          ngModel.$setViewValue(el.val());
          ngModel.$render();
        });
      });
    }
  }
});

示例标记：

  <div ng-form="myForm">
    <input id="userUpload" ng-model="filename" valid-file name="userUpload" required type="file" accept="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" />
    <button ng-disabled="myForm.$invalid" type="submit" class="btn btn-primary"><i class="icon-white icon-ok"></i>&nbsp;Ok</button>
    <p>
      Input is valid: {{myForm.userUpload.$valid}}
      <br>Selected file: {{filename}}
    </p>
  </div>

查看my working plnkr example。

Answer 2

扩展@joakimbl代码我会建议像这样直接

.directive('validFile',function(){
    return {
        require:'ngModel',
        link:function(scope,el,attrs,ctrl){
            ctrl.$setValidity('validFile', el.val() != '');
            //change event is fired when file is selected
            el.bind('change',function(){
                ctrl.$setValidity('validFile', el.val() != '');
                scope.$apply(function(){
                    ctrl.$setViewValue(el.val());
                    ctrl.$render();
                });
            });
        }
    }
})

在html中你可以像这样使用

<input type="file" name="myFile" ng-model="myFile" valid-file />
<label ng-show="myForm.myFile.$error.validFile">File is required</label>

必需属性不适用于Angular Js中的文件输入

2 个答案: