混入emitter

import emitter from 'element-ui/src/mixins/emitter'

FormItem

FormItem存在以下办法

  validate(trigger, callback = noop) {        this.validateDisabled = false;        const rules = this.getFilteredRule(trigger);        if ((!rules || rules.length === 0) && this.required === undefined) {          callback();          return true;        }        this.validateState = 'validating';        const descriptor = {};        if (rules && rules.length > 0) {          rules.forEach(rule => {            delete rule.trigger;          });        }        descriptor[this.prop] = rules;        const validator = new AsyncValidator(descriptor);        const model = {};        model[this.prop] = this.fieldValue;        validator.validate(model, { firstFields: true }, (errors, invalidFields) => {          this.validateState = !errors ? 'success' : 'error';          this.validateMessage = errors ? errors[0].message : '';          callback(this.validateMessage, invalidFields);          this.elForm && this.elForm.$emit('validate', this.prop, !errors, this.validateMessage || null);        });      }

FormItem有以下监听

this.$on('el.form.blur', this.onFieldBlur);this.$on('el.form.change', this.onFieldChange);

所以，在本人的组件外面，触发这个事件就好了

this.dispatch('ElFormItem', 'el.form.change', self.fileList)

是change还是blur, 看form rules中的规定而定

dispath

dispatch: function dispatch(componentName, eventName, params) {  var parent = this.$parent || this.$root;  var name = parent.$options.componentName;  while (parent && (!name || name !== componentName)) {    parent = parent.$parent;    if (parent) {      name = parent.$options.componentName;    }  }  if (parent) {    parent.$emit.apply(parent, [eventName].concat(params));  }},

能够看出dispath就是始终死循环向上找父级组件。