以角度从请求正文中截取 FormData

【问题标题】：intercept FormData from request body in angular以角度从请求正文中截取 FormData
【发布时间】：2021-07-10 06:16:01
【问题描述】：

发送

let formData = new FormData();
http.post - - - - - - - - - - - formData;

得到

request = { body: FormData }

我想做角截距

if(FormData's value instanceof File) {
    pass without intercept
}

我该怎么做？

或

request = { body : FileFormData(ex: FormData only for File) }

【问题讨论】：

标签： angular request intercept

【解决方案1】：

使用 HttpInterceptor

import { Injectable } from '@angular/core';
import {
  HttpEvent, HttpInterceptor, HttpHandler, HttpRequest
} from '@angular/common/http';

import { Observable } from 'rxjs';

@Injectable()
export class FormDataInterceptor implements HttpInterceptor {

  intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
    // FormData's value instanceof File, something along the lines of
    if(req.body instanceof File) {
        return next.handle(req);
    }
    // Do intended logic here
    return next.handle(req);
  }
}

然后注册拦截器： app.module.ts

providers: [
   { provide: HTTP_INTERCEPTORS, useClass: FormDataInterceptor, multi: true }
]

【讨论】：