我有一个输入按钮，要求上传图像。 html代码看起来像这样：
<input type="file" name="files" data-file="" data-url="../upload/student/image" accept="image/*">
由于该按钮打开了一个我们可以从其中上传图像的Windows屏幕，因此我也尝试使用机器人类，但是并未以某种方式单击该按钮。
WebElement upload= driver.findElement(By.xpath("//*[@id=\"student_image\"]/input[1]"));
upload.click();
Robot robot= new Robot();
StringSelection string= new
StringSelection("C:\\Users\\pradi\\OneDrive\\Desktop\\outline\\RHEST\\avatar.jpg");
Toolkit.getDefaultToolkit().getSystemClipboard().setContents(string,null);
robot.setAutoDelay(1000);
Ctrl+V(Pressed)
robot.keyPress(KeyEvent.VK_CONTROL);
robot.keyPress(KeyEvent.VK_V);
Ctrl+V(Released)
robot.keyRelease(KeyEvent.VK_CONTROL);
robot.keyRelease(KeyEvent.VK_V);
robot.setAutoDelay(2000);
//Press Enter
robot.keyPress(KeyEvent.VK_ENTER);
robot.keyRelease(KeyEvent.VK_ENTER);
显示错误：
org.openqa.selenium.InvalidArgumentException: invalid argument
(Session info: chrome=83.0.4103.61)
Session ID: 28dd9e0fbe4ec0e77ba63ac627a7696f at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at org.openqa.selenium.remote.http.W3CHttpResponseCodec.createException(W3CHttpResponseCodec.java:187)
at org.openqa.selenium.remote.http.W3CHttpResponseCodec.decode(W3CHttpResponseCodec.java:122)
at org.openqa.selenium.remote.http.W3CHttpResponseCodec.decode(W3CHttpResponseCodec.java:49)
at org.openqa.selenium.remote.HttpCommandExecutor.execute(HttpCommandExecutor.java:158)
at org.openqa.selenium.remote.service.DriverCommandExecutor.execute(DriverCommandExecutor.java:83)
at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:552)
at org.openqa.selenium.remote.RemoteWebElement.execute(RemoteWebElement.java:285)
at org.openqa.selenium.remote.RemoteWebElement.click(RemoteWebElement.java:84)
at student.student_form.adding_student(student_form.java:105)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:133)
at org.testng.internal.TestInvoker.invokeMethod(TestInvoker.java:584)
at org.testng.internal.TestInvoker.invokeTestMethod(TestInvoker.java:172)
at org.testng.internal.MethodRunner.runInSequence(MethodRunner.java:46)
at org.testng.internal.TestInvoker$MethodInvocationAgent.invoke(TestInvoker.java:804)
at org.testng.internal.TestInvoker.invokeTestMethods(TestInvoker.java:145)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:146)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:128)
at java.util.ArrayList.forEach(ArrayList.java:1249)
at org.testng.TestRunner.privateRun(TestRunner.java:770)
at org.testng.TestRunner.run(TestRunner.java:591)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:402)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:396)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:355)
at org.testng.SuiteRunner.run(SuiteRunner.java:304)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:53)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:96)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1180)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1102)
at org.testng.TestNG.runSuites(TestNG.java:1032)
at org.testng.TestNG.run(TestNG.java:1000)
at org.testng.remote.AbstractRemoteTestNG.run(AbstractRemoteTestNG.java:115)
at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:251)
at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:77)
只是找出我的代码停止工作的确切点，我在每一行中尝试了println，并从此行upload.click();中发现代码没有工作我正在使用Chrome版本83.0.4103.61
代替；
upload.click();
使用；
uploadElement.sendKeys("path_to_image//example_image.png");
您可以加入等待中
WebDriverWait wait = new WebDriverWait(driver, 30);
wait.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//*[@id=\"student_image\"]/input[1]"))
.sendKeys(C:\\Users\\pradi\\OneDrive\\Desktop\\outline\\RHEST\\avatar.jpg);
请确认xpath并且存在iframe