C# AutoLogin

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 AutoLogin
 {
     public partial class Form1 : Form
     {
         public Form1()
         {
             InitializeComponent();
         }        int step = 0;
        private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
         {
             HtmlElement ClickBtn = null;
             if (step==0)
             {                HtmlDocument doc = webBrowser1.Document;
                for (int i = 0; i < doc.All.Count; i++)
                 {                    if (doc.All[i].TagName.ToUpper().Equals("INPUT"))
                     {                        switch (doc.All[i].Name)
                         {                            case "userLoginId":
                                 //name=userLoginId value="name"
                                 doc.All[i].InnerText = "name";　　// 用户名                                break;
                             //value="password" name=password
                             case "password":                                doc.All[i].InnerText = "password";　　　　　　// 密码
                                break;
                             //INPUT type=submit value=Submit
                             case "btnSubmit":                                ClickBtn = doc.All[i];
                                break;
                        }
                         if (doc.All[i].GetAttribute("type").ToLower().Equals("submit"))
                         {
                             ClickBtn = doc.All[i];
                         }                    }
                }
                 if (ClickBtn != null)
                 {
                     ClickBtn.InvokeMember("Click");　// 点击“登录”按钮
                 }                step = 1;
                 webBrowser1.Navigate("http://url");
             }
             if (step==1)
             {
                 step = 2;
                 webBrowser1.Navigate("http://url");                
             }
             
        }
        private void button1_Click(object sender, EventArgs e)
         {
             string sUrl = txb_Url.Text.Trim();            if (sUrl.Length > 0)
             {                webBrowser1.Navigate(sUrl);
            }
         }        private void Form1_Load(object sender, EventArgs e)
         {
             button1_Click(sender,  e);
         }
     }
 }
namespace AutoLogin
 {
     partial class Form1
     {
         /// <summary>
         /// Required designer variable.
         /// </summary>
         private System.ComponentModel.IContainer components = null;        /// <summary>
         /// Clean up any resources being used.
         /// </summary>
         /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
         protected override void Dispose(bool disposing)
         {
             if (disposing && (components != null))
             {
                 components.Dispose();
             }
             base.Dispose(disposing);
         }        #region Windows Form Designer generated code
        /// <summary>
         /// Required method for Designer support - do not modify
         /// the contents of this method with the code editor.
         /// </summary>
         private void InitializeComponent()
         {
             this.webBrowser1 = new System.Windows.Forms.WebBrowser();
             this.panel1 = new System.Windows.Forms.Panel();
             this.txb_Url = new System.Windows.Forms.TextBox();
             this.button1 = new System.Windows.Forms.Button();
             this.panel1.SuspendLayout();
             this.SuspendLayout();
             // 
             // webBrowser1
             // 
             this.webBrowser1.Dock = System.Windows.Forms.DockStyle.Fill;
             this.webBrowser1.Location = new System.Drawing.Point(0, 0);
             this.webBrowser1.MinimumSize = new System.Drawing.Size(20, 20);
             this.webBrowser1.Name = "webBrowser1";
             this.webBrowser1.Size = new System.Drawing.Size(719, 677);
             this.webBrowser1.TabIndex = 2;
             this.webBrowser1.DocumentCompleted += new System.Windows.Forms.WebBrowserDocumentCompletedEventHandler(this.webBrowser1_DocumentCompleted);
             // 
             // panel1
             // 
             this.panel1.Controls.Add(this.button1);
             this.panel1.Controls.Add(this.txb_Url);
             this.panel1.Dock = System.Windows.Forms.DockStyle.Top;
             this.panel1.Location = new System.Drawing.Point(0, 0);
             this.panel1.Name = "panel1";
             this.panel1.Size = new System.Drawing.Size(719, 24);
             this.panel1.TabIndex = 3;
             // 
             // txb_Url
             // 
             this.txb_Url.Dock = System.Windows.Forms.DockStyle.Left;
             this.txb_Url.Location = new System.Drawing.Point(0, 0);
             this.txb_Url.Name = "txb_Url";
             this.txb_Url.Size = new System.Drawing.Size(638, 21);
             this.txb_Url.TabIndex = 0;
             this.txb_Url.Text = "http://url";
             // 
             // button1
             // 
             this.button1.Dock = System.Windows.Forms.DockStyle.Right;
             this.button1.Location = new System.Drawing.Point(644, 0);
             this.button1.Name = "button1";
             this.button1.Size = new System.Drawing.Size(75, 24);
             this.button1.TabIndex = 1;
             this.button1.Text = "button1";
             this.button1.UseVisualStyleBackColor = true;
             this.button1.Click += new System.EventHandler(this.button1_Click);
             // 
             // Form1
             // 
             this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
             this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
             this.ClientSize = new System.Drawing.Size(719, 677);
             this.Controls.Add(this.panel1);
             this.Controls.Add(this.webBrowser1);
             this.Name = "Form1";
             this.Text = "auto login";
             this.Load += new System.EventHandler(this.Form1_Load);
             this.panel1.ResumeLayout(false);
             this.panel1.PerformLayout();
             this.ResumeLayout(false);        }
        #endregion
        private System.Windows.Forms.WebBrowser webBrowser1;
         private System.Windows.Forms.Panel panel1;
         private System.Windows.Forms.Button button1;
         private System.Windows.Forms.TextBox txb_Url;
     }
 }