Question

我已经编写了一些代码来向网站发布消息。它工作正常（对于第一个实例），问题是它一直在webBrowser1_DocumentCompleted方法中循环（一遍又一遍地运行SendData方法）。所以我一定不能正确处理这个事件。在运行SendData调用一次后，我希望它返回到最初启动的button1_Start_Click事件。

private void button1_Start_Click(object sender, EventArgs e)
    {



        GetData();


    }


    private void GetData()
    {

        webBrowser1.Navigate(inputURLID);
    }



    private void SendData()
    {

        webBrowser1.Document.GetElementById("subject").SetAttribute("value", textBox2_Subject.Text);//To (username)

        webBrowser1.Document.GetElementById("message").SetAttribute("value", richTextBox1.Text);//Subject

        webBrowser1.Document.GetElementById("Submit").InvokeMember("click");//Message
    }



    private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
    {
        SendData();
    }

Answer 1

问题在于，当您单击“提交”时，将加载新页面并再次为此新页面调用DocumentCompleted。

您可以尝试这样的事情：

bool documentCompleted = false;

private void button1_Start_Click(object sender, EventArgs e)
{
    webBrowser1.Navigate(inputURLID);
    WaitForDocumentCompleted();
    SendData();
    WaitForDocumentCompleted();
}

private void WaitForDocumentCompleted()
{
    while (!documentCompleted)
    {
        Thread.Sleep(100);
        Application.DoEvents(); 
    }

    documentCompleted = false;
}

private void SendData()
{
    webBrowser1.Document.GetElementById("subject").SetAttribute("value", textBox2_Subject.Text);//To (username)
    webBrowser1.Document.GetElementById("message").SetAttribute("value", richTextBox1.Text);//Subject
    webBrowser1.Document.GetElementById("Submit").InvokeMember("click");//Message
}

private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
    documentCompleted = true;
}

Answer 2

我必须发帖，你选择的答案会让你陷入困境。解决方法很简单，您只需要一个变量来告诉您下一个DocumentCompleted事件就是您感兴趣的事件。就像这样：

private bool WaitingForData;

private void GetData()
{
    webBrowser1.Navigate(inputURLID);
    WaitingForData = true;
}

private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
    if (WaitingForData) SendData();
    WaitingForData = false;
}

发布webBrowser1_DocumentCompleted会保持循环

2 个答案: