Command webbrowser

Question

I can not fix the error anyone can help me? ..

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace test
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void button1_Click(object sender, EventArgs e)
{

webBrowser1.Navigate(" http://www.httpsurf.com/ ");

//the debugger tells me that the error in this line
webBrowser1.Document.GetElementById("url").InnerText = textBox1.Text;

webBrowser1.Document.GetElementById("go").InvokeMember("Click");

}

private void textBox1_TextChanged(object sender, EventArgs e)
{

}
}
}

Sam Hobbs · Answer

First please don't use such a large font; it makes it diffcult to see all the code. Second please see my article Introduction to Web Site Scraping .

Javeed M Shaikh · Answer

try this... webBrowser1.Navigate( http://www.httpsurf.com/ ); webBrowser1.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(webBrowser1_DocumentCompleted); // here is the event void webBrowser1_DocumentCompleted(object sender WebBrowserDocumentCompletedEventArgs e) { webBrowser1.Document.GetElementById(Url).InnerText = textBox1.Text; }

Jean Paul · Answer

The error was occurring because the code was accessing Document object which was not created yet (as navigation in progress). Following is the corrected code. webBrowser1.Navigate( http://www.httpsurf.com/ ); webBrowser1.Navigated += (object sender2 WebBrowserNavigatedEventArgs e2) => { //the debugger tells me that the error in this line webBrowser1.Document.GetElementById(url).InnerText = textBox1.Text; //webBrowser1.Document.GetElementById(go).InvokeMember(Click); }; Please note that you have to ensure the event is not called multiple times (delegate invoking click)

bugmenot bugmenot · Answer

I tried that code but it does not work..

Vulpes · Answer

You haven't said what the error is but if there isn't an HTMLElement with an ID of url this expression will be null: webBrowser1.Document.GetElementById(url) and the line you specified will then give an 'object not set to an instance of an object' exception. To prevent the exception you'd therefore need to do this: if (webBrowser1.Document.GetElementById(url) != null) { webBrowser1.Document.GetElementById(url).InnerText = textBox1.Text; }