7

我正在尝试创建简单的表单，如http://angularjs.blogspot.no/2015/03/forms-in-angular-2.html中所述，但是当我添加

import {forms, required} from 'angular2/forms';

在崩溃中

TypeError: Cannot read property 'annotations' of undefined

TypeError: Cannot read property 'annotations' of undefined
    at ReflectionCapabilities.System.register.execute.$__export.annotations (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/reflection/reflection_capabilities.es6!eval:81:40)
    at Reflector.System.register.execute.$__export.annotations (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/reflection/reflector.es6!eval:81:50)
    at DirectiveMetadataReader.System.register.execute.$__export.read (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/compiler/directive_metadata_reader.es6!eval:31:41)
    at eval (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/compiler/compiler.es6!eval:127:35)
    at Array.map (native)
    at Function.System.register.execute.$__export.map (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/facade/collection.es6!eval:172:26)
    at Compiler.System.register.execute.$__export.createSteps (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/compiler/compiler.es6!eval:126:43)
    at Compiler.System.register.execute.$__export._compileTemplate (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/compiler/compiler.es6!eval:164:53)
    at eval (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/compiler/compiler.es6!eval:154:29)
    at Zone.run (http://localhost:9090/node_modules/zone.js/zone.js:87:19)

-----async gap-----
Error
    at Function.System.register.execute.$__export.then (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/facade/async.es6!eval:35:28)
    at Compiler.System.register.execute.$__export._compile (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/compiler/compiler.es6!eval:153:42)
    at Compiler.System.register.execute.$__export.compile (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/compiler/compiler.es6!eval:134:34)
    at eval (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/application.es6!eval:73:23)
    at Function.System.register.execute.$__export.apply (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/facade/lang.es6!eval:317:23)

-----async gap-----
Error
    at _AsyncInjectorStrategy.System.register.execute._AsyncInjectorStrategy.instantiate (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/di/injector.es6!eval:297:17)
    at Injector.System.register.execute.$__export._getByKey (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/di/injector.es6!eval:138:33)
    at Injector.System.register.execute.$__export.asyncGet (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/di/injector.es6!eval:112:25)
    at eval (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/application.es6!eval:113:39)

-----async gap-----
Error
    at VmTurnZone.System.register.execute.$__export._createInnerZone (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/zone/vm_turn_zone.es6!eval:61:45)
    at new VmTurnZone (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/zone/vm_turn_zone.es6!eval:29:34)
    at _createVmZone (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/application.es6!eval:101:16)
    at bootstrap (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/application.es6!eval:110:16)
    at y.main (http://localhost:9090/app.js!eval:10:12)
    at http://localhost:9090/?:42:21

-----async gap-----
Error
    at VmTurnZone.System.register.execute.$__export._createInnerZone (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/zone/vm_turn_zone.es6!eval:61:25)
    at new VmTurnZone (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/zone/vm_turn_zone.es6!eval:29:34)
    at _createVmZone (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/application.es6!eval:101:16)
    at bootstrap (http://localhost:9090/node_modules/angular/dist/js/prod/es6/angular2/src/core/application.es6!eval:110:16)
    at y.main (http://localhost:9090/app.js!eval:10:12)
    at http://localhost:9090/?:42:21

无法理解该错误消息的含义，我也找不到该表单指令定义的位置。

更新：“未定义”实际上是一个“表单”指令，在 angular2/modules/angular2/src/forms 中似乎确实缺少它。然后 DirectiveMetadataReader 将“未定义”进一步传递给反射器，最终导致异常。很高兴在模板中签入。

4

1 回答 1

2

看起来 Victor 博客中的示例与您使用的版本不匹配（那些日子 API 变化如此之快）。但是现在发布了测试版（这意味着不再有重大更改），所以我创建了具有尽可能接近功能的工作示例：

Angular 2 测试版

import {Component} from 'angular2/core'
import {ControlGroup, FormBuilder, Validators} from 'angular2/common'
...

http://plnkr.co/edit/ae1WEgQJWPMdEgoweMGd?p=preview 只是为了检查它走了多远（足够远！）。

从 Angular 版本：2.0.0-rc.1

所有使用 angular2 的导入都需要更改为 @angular

import {Component} from '@angular/core'
import {ControlGroup, FormBuilder, Validators} from '@angular/common';

有关更多进口清单，请参见此处：-

于 2015-12-16T23:22:06.610 回答