要解决Angular使用自签名证书调用URI时出现“net::ERR_CERT_AUTHORITY_INVALID”错误，可以使用以下方法：

1. 忽略证书验证： 在Angular的HTTP请求中设置withCredentials: true，这会使请求在发送时忽略证书验证。但是这会使通信变得不安全，不建议在生产环境中使用。

   import { HttpClient } from '@angular/common/http';
   
   constructor(private http: HttpClient) {}
   
   // 发送HTTP请求
   this.http.get('https://your-uri', { withCredentials: true }).subscribe(
     response => {
       // 处理响应
     },
     error => {
       // 处理错误
     }
   );
   

2. 导入自签名证书： 将自签名证书导入到Angular项目中，并在请求之前将其添加到可信证书存储中。

   • 将证书文件（.pem或.crt）放置在Angular项目的assets文件夹中。

   • 在Angular项目的tsconfig.json文件中，将"assets"数组中的路径添加到“include”数组中。例如：

     {
       "compilerOptions": {
         // ...
       },
       "include": [
         // ...
         "src/assets/*.pem" // 或者 "src/assets/*.crt"
       ]
     }
     

   • 创建一个名为certificate.service.ts的服务，用于导入和添加证书到可信证书存储中：

     import { Injectable } from '@angular/core';
     
     @Injectable({
       providedIn: 'root'
     })
     export class CertificateService {
       importCertificate(): Promise {
         return fetch('/assets/your-certificate.pem') // 或者 '/assets/your-certificate.crt'
           .then(response => response.text())
           .then(certificate => {
             return window.crypto.subtle.importKey(
               'spki',
               this.str2ab(atob(certificate)), // 将证书从Base64转换为ArrayBuffer
               {
                 name: 'RSA-OAEP',
                 hash: { name: 'SHA-256' }
               },
               true,
               ['verify']
             );
           })
           .then(cryptoKey => {
             return window.crypto.subtle.exportKey('spki', cryptoKey);
           })
           .then(exportedKey => {
             const buf = new Uint8Array(exportedKey);
             const blob = new Blob([buf], { type: 'application/x-x509-ca-cert' });
             const cert = new File([blob], 'your-certificate.pem', { type: 'application/x-x509-ca-cert' });
     
             return window.crypto.subtle.digest('SHA-256', buf)
               .then(hashBuffer => {
                 const hashArray = Array.from(new Uint8Array(hashBuffer));
                 const hashHex = hashArray.map(byte => ('00' + byte.toString(16)).slice(-2)).join('');
     
                 return { cert, hash: hashHex };
               });
           })
           .then(({ cert, hash }) => {
             return window.crypto.subtle.digest('SHA-1', new TextEncoder().encode(hash))
               .then(hashBuffer => {
                 const hashArray = Array.from(new Uint8Array(hashBuffer));
                 const hashHex = hashArray.map(byte => ('00' + byte.toString(16)).slice(-2)).join('');
     
                 return { cert, hash: hashHex };
               });
           })
           .then(({ cert, hash }) => {
             return new Promise((resolve, reject) => {
               const reader = new FileReader();
               reader.onloadend = () => {
                 resolve(reader.result);
               };
               reader.onerror = reject;
               reader.readAsArrayBuffer(cert);
             })
               .then(arrayBuffer => {
                 const certArray = Array.from(new Uint8Array(arrayBuffer));
                 const blob = new Blob([new Uint8Array(certArray)], { type: 'application/x-x509-ca-cert' });
     
                 const anchor = document.createElement('a');
                 anchor.style.display = 'none';
                 anchor.href = URL.createObjectURL(blob);
                 anchor.download = 'your-certificate.pem';
                 document.body.appendChild(anchor);
                 anchor.click();
                 document.body.removeChild(anchor);
               });
           })
           .catch(error => {
             console.error('Failed to import certificate:', error);
           });
       }
     
       private str2ab(str: string): ArrayBuffer {
         const buf = new ArrayBuffer(str.length);
         const bufView = new Uint8Array(buf);
     
         for (let i = 0, strLen = str.length; i <