Npm 我需要实现一个功能，在angular应用程序中使用热敏打印机。不幸的是，我没有尝试'；我不会成功的

我正在使用ng热敏打印，但出现了一些错误。 从属关系的版本 安圭拉：6 ng热敏打印：0.1.5

package.json

"@agm/core": "1.0.0-beta.3",
"@angular/animations": "^6.1.7",
"@angular-devkit/build-angular": "~0.7.0",
"@angular/cli": "~6.1.2",
"@angular/compiler-cli": "^6.1.0",
"@angular/language-service": "^6.1.0",
"@angular/common": "^6.1.0",
"@angular/compiler": "^6.1.0",
"@angular/core": "6.1.0",
"@angular/fire": "^5.0.2",
"@angular/forms": "^6.1.0",

app.component.ts

import { Component, OnDestroy } from "@angular/core";
import { ApiService } from "../../services/api.service";
import { PrintService, UsbDriver, WebPrintDriver } from "ng-thermal-print";

@Component({
  selector: "app-dashboard",
  templateUrl: "./dashboard.component.html",
})
export class DashboardComponent implements OnDestroy {
  status: boolean = false;
  usbPrintDriver: UsbDriver;
  webPrintDriver: WebPrintDriver;
  ip: string = "";

  public constructor(
    public api: ApiService,
    private printService: PrintService
  ) {
    this.usbPrintDriver = new UsbDriver();
    this.printService.isConnected.subscribe((result) => {
      this.status = result;
      if (result) {
        console.log("Connected to printer!!!");
      } else {
        console.log("Not connected to printer.");
      }
    });
  }

  requestUsb() {
    this.usbPrintDriver.requestUsb().subscribe((result) => {
      this.printService.setDriver(this.usbPrintDriver, "ESC/POS");
    });
  }

  connectToWebPrint() {
    this.webPrintDriver = new WebPrintDriver(this.ip);
    this.printService.setDriver(this.webPrintDriver, "WebPRNT");
  }

  print(data) {
    this.printService
      .init()
      .setBold(true)
      .writeLine("Hello World")
      .setBold(false)
      .feed(4)
      .cut("full")
      .flush();
  }

  ngOnDestroy() {}
}

app.component.html

<button class="btn btn-success">Print Order</button>

打印顺序

我得到了一些错误，比如对象（…）不是函数 我已安装用于usb检测的@types/w3c web usb

我附上了错误的图片。 请帮帮我