我们可以在Angular的HTTP拦截器中处理这个问题。具体步骤如下：

1. 创建一个新的interceptor.service.ts文件

import { Injectable } from '@angular/core';
import { HttpInterceptor, HttpHandler, HttpRequest, HttpErrorResponse } from '@angular/common/http';
import { Observable, throwError } from 'rxjs';
import { catchError } from 'rxjs/operators';

@Injectable({
  providedIn: 'root'
})
export class InterceptorService implements HttpInterceptor { 

  constructor() { }

  intercept(request: HttpRequest, next: HttpHandler): Observable {
    return next.handle(request).pipe(
      catchError((err: HttpErrorResponse) => {
        if (err.status === 200) {
          return next.handle(request.clone({ headers: request.headers.set('Content-length', '0') }));
        } else {
          return throwError(err);
        }
      })
    )
  }
}

2. 在app.module.ts文件中注入interceptor.service

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { HttpClientModule, HTTP_INTERCEPTORS } from '@angular/common/http';
import { AppComponent } from './app.component';
import { InterceptorService } from './interceptor.service';

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    HttpClientModule
  ],
  providers: [
    {
      provide: HTTP_INTERCEPTORS,
      useClass: InterceptorService,
      multi: true
    }
  ],
  bootstrap: [AppComponent]
})
export class AppModule { }

这样就解决了响应代码为200被视为错误的问题。