Question

我正在使用Microsoft.ApsNetCore.Cors 2.2

“通过'exampleapi.local'访问XMLHttpRequest 来自来源“ example.local”的信息已被CORS政策阻止：请求中没有'Access-Control-Allow-Origin'标头资源。”

我以此设置设置

=IFERROR(INDEX(Returns!$B:$B,MATCH($A2,Returns!$A:$A,0)),"")

但是它不起作用，总是出现相同的错误

Answer 1

我刚刚失去了几分钟试图找出为什么CORS没有从工作的请求http://localhost:8080，我根据官方文档已经设置。

好吧，因为我在URL的末尾添加了一个'/'。因此，从允许的来源中删除“ /”。

Microsoft文档上甚至还有关于此的注释！

注意：URL不得包含斜杠（/）。如果网址以/终止，比较返回false并且没有头返回。

Answer 2

简单易行的方法。

安装软件包

from PyQt5 import QtCore, QtGui, QtWidgets import urllib import speech_recognition as sr import threading import time import import_ipynb from gui import Ui_Function class Ui_welcome(object): def openfunc(self): self.window = QtWidgets.QMainWindow() self.ui = Ui_Function() self.ui.setupUi(self.window) welcome.hide() self.window.show() def setupUi(self, welcome): welcome.setObjectName("welcome") welcome.resize(739, 600) welcome.setStyleSheet("Background-color: #696969;") self.centralwidget = QtWidgets.QWidget(welcome) self.centralwidget.setObjectName("centralwidget") self.label = QtWidgets.QLabel(self.centralwidget) self.label.setGeometry(QtCore.QRect(70, 90, 601, 61)) self.label.setStyleSheet("\n" "font-family: Lucida Console;\n" "font-size: 25px;\n" "font-weight: bold;\n" "font-style: italic;\n" "color: #ffffff;\n" "") self.label.setObjectName("label") self.pushButton = QtWidgets.QPushButton(self.centralwidget) self.pushButton.setGeometry(QtCore.QRect(240, 250, 281, 71)) self.pushButton.setStyleSheet("QPushButton{\n" "color: #ffffff;\n" "background-color: #ff6347;\n" "Border-radius: 30px;\n" "font-size:30px\n" "}\n" "QPushButton:hover{\n" "color: #ffffff;\n" "background-color: #ff6347;\n" "Border-radius: 30px;\n" "background-color: #ff4500;\n" "font-weight: bold;\n" "}") self.pushButton.setObjectName("pushButton") self.pushButton.clicked.connect(self.openfunc) welcome.setCentralWidget(self.centralwidget) self.retranslateUi(welcome) QtCore.QMetaObject.connectSlotsByName(welcome) def retranslateUi(self, welcome): _translate = QtCore.QCoreApplication.translate welcome.setWindowTitle(_translate("welcome", "MainWindow")) self.label.setText(_translate("welcome", "Welcome To Book Recommendation System")) self.pushButton.setText(_translate("welcome", "Let\'s get started")) if __name__ == "__main__": import sys app = QtWidgets.QApplication(sys.argv) welcome = QtWidgets.QMainWindow() ui = Ui_welcome() ui.setupUi(welcome) welcome.show() app.exec_()

将以下代码放在 startup.cs 文件

from PyQt5 import QtCore, QtGui, QtWidgets import urllib import speech_recognition as sr import threading import time import import_ipynb from Untitled12 import * def connected(host="http://google.com"): try: urllib.request.urlopen(host) return True except: return False class Ui_Function(object): def setupUi(self, Function): Function.setObjectName("Function") Function.resize(737, 600) Function.setStyleSheet("Background-color: #696969;") self.centralwidget = QtWidgets.QWidget(Function) self.centralwidget.setObjectName("centralwidget") self.lineEdit = QtWidgets.QLineEdit(self.centralwidget) self.lineEdit.setGeometry(QtCore.QRect(50, 70, 601, 31)) self.lineEdit.setStyleSheet("color: #ffffff") self.lineEdit.setObjectName("lineEdit") self.lineEdit.setPlaceholderText("Enter Book Name...") self.label = QtWidgets.QLabel(self.centralwidget) #self.label.setGeometry(QtCore.QRect(50, 30, 151, 17)) self.label.setGeometry(QtCore.QRect(50, 40, 191, 17)) self.label.setStyleSheet("QLabel{\n" "color: #ffffff;\n" "font-family: Lucida Console;\n" "font-size: 15px;\n" "}") self.label.setObjectName("label") self.label_2 = QtWidgets.QLabel(self.centralwidget) self.label_2.setGeometry(QtCore.QRect(320, 120, 67, 17)) self.label_2.setObjectName("label_2") self.label_2.setStyleSheet("QLabel{\n" "color: #ffffff;\n" "font-family: Lucida Console;\n" "font-size: 20px;\n" "}") self.label_3 = QtWidgets.QLabel(self.centralwidget) self.label_3.setGeometry(QtCore.QRect(50, 150, 311, 21)) self.label_3.setObjectName("label_3") self.label_3.setStyleSheet("QLabel{\n" "color: #ffffff;\n" "font-family: Lucida Console;\n" "font-size: 15px;\n" "}") self.pushButton = QtWidgets.QPushButton(self.centralwidget) self.pushButton.setGeometry(QtCore.QRect(50, 180, 121, 41)) self.pushButton.setObjectName("pushButton") self.pushButton.setStyleSheet("QPushButton{\n" "color: #ffffff;\n" "background-color: #ff6347;\n" "Border-radius: 10px;\n" "}\n" "QPushButton:hover{\n" "color: #ffffff;\n" "background-color: #ff6347;\n" "Border-radius: 10px;\n" "background-color: #ff4500;\n" "font-weight:bold;\n" "}") self.textEdit = QtWidgets.QTextEdit(self.centralwidget) self.textEdit.setGeometry(QtCore.QRect(60, 320, 601, 231)) self.textEdit.setObjectName("textEdit") self.textEdit.setStyleSheet("QTextEdit{\n" "Background-color: #ffffff;\n" "}") self.label_4 = QtWidgets.QLabel(self.centralwidget) self.label_4.setGeometry(QtCore.QRect(60, 290, 141, 21)) self.label_4.setObjectName("label_4") self.label_4.setStyleSheet("QLabel{\n" "color: #ffffff;\n" "font-family: Lucida Console;\n" "font-size: 15px;\n" "}") self.pushButton_2 = QtWidgets.QPushButton(self.centralwidget) self.pushButton_2.setGeometry(QtCore.QRect(538, 110, 111, 41)) self.pushButton_2.setObjectName("pushButton_2") self.pushButton_2.setStyleSheet("QPushButton{\n" "color: #ffffff;\n" "background-color: #ff6347;\n" "Border-radius: 10px;\n" "}\n" "QPushButton:hover{\n" "color: #ffffff;\n" "Background-color: #ff6347;\n" "Border-radius: 10px;\n" "background-color: #ff4500;\n" "font-weight: bold;\n" "}") #self.pushButton_2.clicked.connect(Untitled12.give_rec("Angel of Hope")) self.label_5 = QtWidgets.QLabel(self.centralwidget) self.label_5.setGeometry(QtCore.QRect(60, 220, 241, 21)) self.label_5.setObjectName("label_5") self.label_5.setStyleSheet("QLabel{\n" "color: #ffffff;\n" "font-family: Lucida Console;\n" "}") self.comboBox = QtWidgets.QComboBox(self.centralwidget) self.comboBox.setGeometry(QtCore.QRect(400, 180, 251, 31)) self.comboBox.setStyleSheet("QcomboBox{\n" "color: #ffffff;\n" "Background-color: #ffffff;\n" "font-family: Lucida Console;\n" "}") self.comboBox.setObjectName("comboBox") self.comboBox.addItem("Your Book Name here...") self.comboBox.currentIndexChanged.connect(self.changeText) Function.setCentralWidget(self.centralwidget) self.retranslateUi(Function) QtCore.QMetaObject.connectSlotsByName(Function) def changeText(self, index): self.lineEdit.setText(self.comboBox.itemText(index)) def retranslateUi(self, Function): _translate = QtCore.QCoreApplication.translate Function.setWindowTitle(_translate("Function", "MainWindow")) self.label.setText(_translate("Function", "Enter the Book Name:")) self.label_2.setText(_translate("Function", "OR")) self.label_3.setText( _translate("Function", "Write the Book Name by your Voice:") ) self.pushButton.setText(_translate("Function", "Click and Say")) self.label_4.setText(_translate("Function", "Recommendations:")) self.pushButton_2.setText(_translate("Function", "Search")) self.label_5.setText(_translate("Function", "Suggestions...")) class SpeechWorker(QtCore.QObject): messageChanged = QtCore.pyqtSignal(str) itemsChanged = QtCore.pyqtSignal(list) def speech(self): threading.Thread(target=self._speech, daemon=True).start() def _speech(self): if connected(): r = sr.Recognizer() with sr.Microphone() as source: r.adjust_for_ambient_noise(source) self.messageChanged.emit("Listening...") time.sleep(1) # read the audio data from the default microphone try: audio_data = r.listen(source, timeout=5) except sr.WaitTimeoutError as e: print("Timeout; {0}".format(e)) self.messageChanged.emit("Time over") time.sleep(1) self.messageChanged.emit("Recognizing...") time.sleep(1) # convert speech to text text = r.recognize_google(audio_data, language="en-UK", show_all=True) try: self.messageChanged.emit("You said:") self.itemsChanged.emit([]) list1 = [] if len(text) > 0: print(len(text["alternative"])) for x in range(0, len(text["alternative"])): list1.append(text["alternative"][x]["transcript"]) self.itemsChanged.emit(list1) else: time.sleep(1) self.messageChanged.emit("\tNothing") except LookupError: time.sleep(1) self.messageChanged.emit("Could not Understand Value") except sr.UnknownValueError: time.sleep(1) self.messageChanged.emit( "Voice Recognition could not understand audio" ) except sr.RequestError as e: time.sleep(1) self.messageChanged.emit( "Voice Recognition could not request results ; {0}".format(e) ) else: time.sleep(1) self.messageChanged.emit( "NO Internet Connection. \nCheck your Internet Connection" ) time.sleep(1) self.messageChanged.emit("Completed") time.sleep(2) self.messageChanged.emit("Suggestions...") class Function(QtWidgets.QMainWindow, Ui_Function): def __init__(self, parent=None): super(Function, self).__init__(parent) self.setupUi(self) self.worker = SpeechWorker() self.worker.messageChanged.connect(self.updateMessage) self.worker.itemsChanged.connect(self.updateItems) self.pushButton.clicked.connect(self.worker.speech) self.pushButton_2.clicked.connect(self.updateEditBox) @QtCore.pyqtSlot(str) def updateMessage(self, message): self.label_5.setText(message) self.label_5.adjustSize() @QtCore.pyqtSlot(list) def updateItems(self, items): self.comboBox.clear() self.comboBox.addItems(items) @QtCore.pyqtSlot() def updateEditBox(self): print(self.lineEdit.text()) string=give_rec(self.lineEdit.text()) self.textEdit.clear() self.textEdit.setText("\tRecommendations of "+self.lineEdit.text().title()+"\t") i=1 for names in string: self.textEdit.append(str(i)+" - "+str(names)) i=i+1 self.comboBox.clear() self.lineEdit.setText("") if __name__ == "__main__": import sys app = QtWidgets.QApplication(sys.argv) w = Function() w.show() app.exec_()

Answer 3

这是这里提供的示例：ASP.NET Core 2.2

public void ConfigureServices(IServiceCollection services)
    {
        services.AddCors(options =>
        {
            options.AddPolicy("AllowSpecificOrigin",
                builder => builder.WithOrigins("http://example.com"));
        });
    }

    public void Configure(IApplicationBuilder app, IHostingEnvironment env, 
        ILoggerFactory loggerFactory)
    {
        loggerFactory.AddConsole();

        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        // Shows UseCors with named policy.
        app.UseCors("AllowSpecificOrigin");

        app.Run(async (context) =>
        {
            await context.Response.WriteAsync("Hello World!");
        });
    }

最终在控制器或动作上像这样使用它：

[EnableCors("AllowSpecificOrigin")]

还出于某种原因，请确保在app.UseMVC之前先调用app.UseCors。

如果您需要的只是来自单一来源的CORS，您可以使用没有政策的简单解决方案：

public void ConfigureServices(IServiceCollection services)
{
    services.AddCors();
}
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
    app.UseCors(
        options => options.WithOrigins("http://example.com").AllowAnyMethod()
    );

    app.UseMvc();
}

Answer 4

艾米的评论正确。 CORS标头需要由目标服务器而不是您的目标服务器来设置。

如果您尝试连接到其他端口上的API，但在同一IP地址上本地运行，则会经常遇到CORS问题（最常见的示例是localhost：<>尝试ping localhost <>，等等。）。

如果您尝试使用Google chrome在本地计算机上运行此程序，则可以下载以下扩展程序，该扩展程序可用于启用和禁用CORS规则，以便您可以在本地进行测试： Allow CORS: Access-Control-Allow-Origin

Answer 5

我知道这是一个老问题，但是如果像我一样，您正在使用appsettings.json文件进行配置，请确保添加以下内容：

 "cors": {
"rules": [
  {
    "origin": "https://localhost:44379",
    "allow": true
  }
]}

这种简单的添加使一切神奇地为我工作。

在ASP.NET Core中允许Cors Origin

5 个答案: