html页面里有一个input element，通过语法[(ngModel)]双向绑定到model hero的name字段。
上图的方法负责更新element的property：
/** * @license * Copyright Google LLC All Rights Reserved. * * Use of this source code is governed by an MIT-style license that can be * found in the LICENSE file at https://angular.io/license */ /** * Update a property on a selected element. * * Operates on the element selected by index via the {@link select} instruction. * * If the property name also exists as an input property on one of the element's directives, * the component property will be set instead of the element property. This check must * be conducted at runtime so child components that add new `@Inputs` don't have to be re-compiled * * @param propName Name of property. Because it is going to DOM, this is not subject to * renaming as part of minification. * @param value New value to write. * @param sanitizer An optional function used to sanitize the value. * @returns This function returns itself so that it may be chained * (e.g. `property('name', ctx.name)('title', ctx.title)`) * * @codeGenApi */
