需要在发送HTTP Post请求时设置请求头的Content-Type为undefined。
以下是示例代码:
const formData = new FormData();
formData.append('name', 'John');
const headers = new HttpHeaders();
headers.set('Content-Type', undefined);
this.http.post('https://example.com/api/user', formData, {headers})
.subscribe(response => console.log(response));