DocumentCompleted firing only once

问题:

I have a WebBrowser inside a form and I want to do some automation with it. I click a button inside a windows form that commands the Navigate method of the WebBrowser to a certain page. Then I automatically click a link after DocumentCompleted has fired but after that I want to also click a Button that exists in the new page that appeared by clicking the link. It seems DocumentCompleted fires only when I click the button in the windows form not when I automatically click the a link inside the webpage.

    void BtnTestClick(object sender, EventArgs e)
    {
        webBrowser1.Navigate(@"https://play.google.com/apps/");
        webBrowser1.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(WebBrowser_DocumentCompleted);     
    }

    public void WebBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
    {

        var webBrowser = sender as WebBrowser;
        //webBrowser.DocumentCompleted -= WebBrowser_DocumentCompleted;

        // test to see if we're on fist CONFIRM page then go forward by clicking
        var links = webBrowser1.Document.GetElementsByTagName("a");
        foreach (HtmlElement link in links)
        {
            if (link.InnerText == "Proceed anyway")
            {
                link.InvokeMember("click");
            }
        }   // this works

    webBrowser1.Document.GetElementById("gwt-uid-126").InvokeMember("click"); 
    }

After the link.InvokeMember("click"); a new page loads in the webbrowser that has a button which I also want to click ( gwt-uid-126 )

But it doesn't get clicked.

I've also tried:

var elements = webBrowser1.Document.GetElementsByTagName("button");
foreach (HtmlElement file in elements)
{
    if (file.GetAttribute("class") == "GKYRWGTDNX GKYRWGTDLY")
    {
        file.Focus();
        file.InvokeMember("click");

    }
}   

With no luck!

回答1:

From what I see, second click doesn't work because the document is not completely loaded and second click is invoked.

You will have to add another if-else block that handled second document load.

Edit1: I was on phone when I answered this, so couldn't provide any snippet. Following is the change that you can do WebBrowser_DocumentCompleted method.

var links = webBrowser1.Document.GetElementsByTagName("a");
foreach (HtmlElement link in links)
{
    if (link.InnerText == "Proceed anyway")
    {
        link.InvokeMember("click");
    }
}
// following is for the page that is loaded on click of link.
var gwt_uid_126 = webBrowser1.Document.GetElementById("gwt-uid-126");
if(gwt_uid_126 != null)
{
    gwt_uid_126.InvokeMember("click");
}

You might want to check if the WebBrowser_DocumentCompleted method is actually being called on second page load. This might be the reason why second click is not registering.

回答2:

move this part of code in the Constructor or Form_Load:

webBrowser1.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(WebBrowser_DocumentCompleted);

try this instead of using WebBrowserDocumnetCompletedEventHandler:

void btnTestClick(object sender, EventArgs e)
{
    webBrowser1.Navigate(@"https://www.google.com/");

    while (webBrowser1.ReadyState != WebBrowserReadyState.Complete)
        continue;

    var webBrowser = sender as WebBrowser;
    //webBrowser.DocumentCompleted -= WebBrowser_DocumentCompleted;

    // test to see if we're on fist CONFIRM page then go forward by clicking
    var links = webBrowser1.Document.GetElementsByTagName("a");
    foreach (HtmlElement link in links)
    {
        if (link.InnerText == "Proceed anyway")
        {
            link.InvokeMember("click");
        }
    }   // this works

    webBrowser1.Document.GetElementById("gwt-uid-126").InvokeMember("click"); 

}