import execjs import requests from lxml import etree def getRsa(u, p, lt): """ 加密方法 :param u:账号 :param p:密码 :param lt:lt :return:加密值 """ jsPath = r'./des.js' with open(jsPath, "r") as file: desJsCode = file.read() desJsFunction = execjs.compile(desJsCode) rsa = desJsFunction.call("strEnc", u + p + lt, "1", "2", "3") return rsa """ ---------------------------------------------------------------------------------- 第一次请求获取lt和execution的数值 """ header = { "User-Agent": 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/113.0.0.0 Safari/537.36' } loginUrl = """http://cas.upc.edu.cn/cas/login?service=http%3A%2F%2Fjwxt.upc.edu.cn%2Fneusoftcas.jsp""" session = requests.session() one = session.get(loginUrl) loginPageHtml = etree.HTML(one.text) lt = loginPageHtml.xpath(r'//*[@id="lt"]/@value')[0] execution = loginPageHtml.xpath(r'//*[@name="execution"]/@value')[0] u = '2009050216' p = '20020528lykLYK.' ul = len(u) pl = len(p) rsa = getRsa(u, p, lt) _eventId = "submit"

下面是相应的Dart代码实现：

import 'dart:io';
import 'package:http/http.dart' as http;
import 'package:html/parser.dart' show parse;
import 'package:html/dom.dart';

Future<String> getRsa(String u, String p, String lt) async {
  /* 加密方法 */
  File jsFile = File('./des.js');
  String desJsCode = await jsFile.readAsString();
  var context = await execjs.createContext(desJsCode);
  String rsa = await context.callMethod("strEnc", [u + p + lt, "1", "2", "3"]);
  return rsa;
}

Future<void> main() async {
  /* 第一次请求获取lt和execution的数值 */
  var headers = {
    "User-Agent":
        'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/113.0.0.0 Safari/537.36'
  };
  var loginUrl =
      "http://cas.upc.edu.cn/cas/login?service=http%3A%2F%2Fjwxt.upc.edu.cn%2Fneusoftcas.jsp";
  var session = http.Client();
  var response = await session.get(Uri.parse(loginUrl), headers: headers);
  var document = parse(response.body);
  var lt = document.querySelector('#lt')?.attributes['value'] ?? "";
  var execution = document.querySelector('[name="execution"]')?.attributes['value'] ?? "";
  var u = '2009050216';
  var p = '20020528lykLYK.';
  var rsa = await getRsa(u, p, lt);
  var _eventId = "submit";
}

需要注意的是，由于Dart是一门静态类型语言，因此需要显式地声明变量类型。此外，Dart中没有像Python中的execjs库一样可以直接使用JavaScript代码，因此需要使用dart-js库来实现JavaScript代码的调用。