C#怎么调用浏览器去登陆网页

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

/////引入ShellExecute函数/////////
[DllImport("shell32.dll")]
public static extern int ShellExecute(
IntPtr hwnd,
StringBuilder lpszOp,
StringBuilder lpszFile,
StringBuilder lpszParams,
StringBuilder lpszDir,
int FsShowCmd);
/////引入ShellExecute函数/////////
private void button1_Click(object sender, EventArgs e)
{
/////调用ShellExecute函数打开网站/////////
ShellExecute(IntPtr.Zero, new StringBuilder("Open"), new StringBuilder("http://www.baidu.com/"), new StringBuilder(""), new StringBuilder(""), 1);