createToken() {
    this._tokenService
        .getAuth(this.userId, this.token)
        .subscribe(res => 
        {}, 
        error => {
            console.log(error);
        });
    }

    getAuth(upn, token) {
        var param = {
            Upn: upn,
            Token: token
        };

        console.log(param);
        
        return this._http.post(
            this.REST_API_ADDR + "auth", 
            param, 
            this.getAuthRequestHeader()
        );
    }

    getAuthRequestHeader() {
        console.log("header");

        const authHeaders = new HttpHeaders({
            'Content-Type':'application/json',
        });

        return { headers: authHeaders };
    }

尝试使用 getAuth 请求来存储令牌。该请求不会调用 API 并引发错误。

TypeError: Cannot read properties of undefined (reading 'length') at HttpHeaders.push../node_modules/@angular/common/fesm5/http.js.HttpHeaders.applyUpdate (http.js:199) at http.js:170 at Array.forEach () at HttpHeaders.push../node_modules/@angular/common/fesm5/http.js.HttpHeaders.init (http.js:170) at HttpHeaders.push../node_modules/@angular/common/fesm5/http.js.HttpHeaders.forEach (http.js:235) at Observable._subscribe (http.js:1435) at Observable.push../node_modules/rxjs/_esm5/internal/Observable.js.Observable._trySubscribe (Observable.js:42) at Observable.push../node_modules/rxjs/_esm5/internal/Observable.js.Observable.subscribe (Observable.js:28) at MapOperator.push../node_modules/rxjs/_esm5/internal/operators/map.js.MapOperator.call (map.js:18) at Observable.push../node_modules/rxjs/_esm5/internal/Observable.js.Observable.subscribe (Observable.js:23)

您能告诉我发生此错误时要检查哪个部分吗？ 另外，如果您知道错误的原因以及如何解决它，请告诉我。