Angular2 RC6 HttpModule手动注入 [英] Angular2 RC6 HttpModule manual injection

问题描述

我正在将项目从angular2 RC4迁移到RC6，并且我有一个需要Http的自定义表单验证器. 在迁移之前，我将ReflectiveInjector与HTTP_PROVIDERS一起使用，但是对于RC6，由于不再支持HTTP_PROVIDERS或不再存在，因此不再可行. 这是Validator中的静态方法:

I'm migrating a project from angular2 RC4 to RC6 and I have a custom Form Validator which needs Http. Before the migration I used the ReflectiveInjector with the HTTP_PROVIDERS, but with RC6 this is not possible anymore as HTTP_PROVIDERS is deprecated, respectively not present anymore. This is the static method in the Validator:

    static checkVat(control: FormControl) {
    let checkVatUrl = "http://localhost:8080/checkvat";


    let injector = ReflectiveInjector.resolveAndCreate([HTTP_PROVIDERS]);
    let http = injector.get(Http);
    let authHttp = new AuthHttp(new AuthConfig(), http);

    if (control.value === "") {
        return new Observable((obs: any) => {
            obs.next(null);
            obs.complete();
        });
    } else {
        return authHttp.get(checkVatUrl + "/" + control.value)
            .map((data: Response) => {
                if (data.json().valid) {
                    return null;
                } else {
                    let reason = "isNotValidVat";
                    return {[reason]: true};
                }
            })
            .catch(function (e) {
                return new Observable((obs: any) => {
                    obs.complete();
                });
            });
    }
}

仅用HttpModule替换HTTP_PROVIDERS不起作用，我在stackoverflow上发现了类似的问题(

Just replacing HTTP_PROVIDERS with HttpModule didn't work, I found a similar problem here on stackoverflow (NG2 RC5: HTTP_PROVIDERS is deprecated) regarding testing, but the only answer is specific for testing.

如果对此自定义验证程序有另一种或更佳的解决方案，我也应该对此开放.

How do I manually "inject" Http or HttpModule with RC6, if there is another or better solution for this custom Validator I'm open to that too.

谢谢.

更新: checkVat方法是静态的，这就是为什么我不得不使用ReflectiveInjector而不是像其他任何地方一样通过构造函数注入它的原因. 自定义验证器的用法如下:

UPDATE: The checkVat method is static, that is why I had to use the ReflectiveInjector and not just inject it via the constructor, like everywhere else. The custom Validator gets used like this:

this.vatCtrl = new FormControl("", Validators.compose([Validators.pattern(this.vatService.vatPattern)]),VatValidator.checkVat);

UPDATE2: 借助GüntherZöchbauer的答案，我对代码进行了如下更改，以使其在没有静态功能且无需手动注入的情况下工作:

UPDATE2: With the help of Günther Zöchbauer's answer I changed the Code as follows to get it working without a static function and no need for manual injection:

验证者:

@Injectable()

导出类VatValidator {

export class VatValidator {

constructor(private http: Http) {
}

checkVat(control: FormControl) {

    let checkVatUrl = "http://localhost:8080/checkvat";

    let authHttp = new AuthHttp(new AuthConfig(), this.http);

    if (control.value === "") {
        return new Observable((obs: any) => {
            obs.next(null);
            obs.complete();
        });
    } else {
        return authHttp.get(checkVatUrl + "/" + control.value)
            .map((data: Response) => {
                if (data.json().valid) {
                    return null;
                } else {
                    let reason = "isNotValidVat";
                    return {[reason]: true};
                }
            })
            .catch(function (e) {
                return new Observable((obs: any) => {
                    obs.complete();
                });
            });
    }

}

}

在具有FormControl的组件中:

In the component which has the FormControl:

    constructor(private vatValidator: VatValidator) {

    this.vatCtrl = new FormControl("", Validators.compose([Validators.pattern(vatPattern)]), this.vatValidator.checkVat.bind(this.vatValidator));

}

推荐答案

如果稍微更改验证器类，则不需要静态方法

If you change your validator class a bit, you don't need a static method

@Injectable()
class PatternValidator {
  constructor(private http:Http){}

  // this is a method that returns a validator function  
  // configured with a pattern
  pattern(pattern) {
    return (control:Control) => {
      this.http.get(...)

    ...
    }
  }
}

您可以像这样使用它:

• 将其注入到您的组件中，以便DI在(Http)中传递其依赖项

• inject it to your component so DI passes it's dependencies in (Http)

constructor(private pattern:PatternValidator) {}

• 通过bind(pattern)传递它，以便.this继续在验证器函数中工作
• pass it with bind(pattern) so .this keeps working inside the validator function

this.vatCtrl = new FormControl("", 
    Validators.compose([
        this.pattern(this.vatService.vatPattern).bind(this.pattern)
    ]), VatValidator.checkVat);

另请参阅 以角度2手动注入Http

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