GridView

Question

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)

{

TextBox UserName = (TextBox)GridView1.Rows[e.RowIndex].FindControl("TextBox1");

string EmailAddress = GridView1.DataKeys[e.RowIndex].Values["EmailAddress"].ToString();

TextBox FirstName = (TextBox)GridView1.Rows[e.RowIndex].FindControl("TextBox3");

TextBox LastName = (TextBox)GridView1.Rows[e.RowIndex].FindControl("TextBox4");

TextBox Password = (TextBox)GridView1.Rows[e.RowIndex].FindControl("Password");

TextBox ConformPassword = (TextBox)GridView1.Rows[e.RowIndex].FindControl("ConformPassword");

TextBox Address = (TextBox)GridView1.Rows[e.RowIndex].FindControl("TextBox7");

DropDownList State = (DropDownList)GridView1.Rows[e.RowIndex].FindControl("DDL1");

DropDownList City = (DropDownList)GridView1.Rows[e.RowIndex].FindControl("DDL2");

Con.Open();

String S = "Update Registration set UserName='" + UserName.Text + "',FirstName='" + FirstName.Text + "',LastName='" + LastName.Text + "',Password='" + Password.Text + "',ConformPassword='" + ConformPassword.Text + "',Address='" + Address.Text + "',State='" + State.SelectedItem + "',City='" + City.SelectedItem + "' where EmailAddress='" + EmailAddress + "'";

//string S = "Update Registration set UserName=@p1,FirstName=@p3,LastName=@p4,Password=@p5,ConformPassword=@p6,Address=@p7,State=@p8,City=@p9 where EmailAddress=@p2";

SqlCommand Cmd = new SqlCommand(S, Con);

//Cmd.Parameters.AddWithValue("@p1", UserName);

//Cmd.Parameters.AddWithValue("@p2", EmailAddress);

//Cmd.Parameters.AddWithValue("@p3", FirstName);

//Cmd.Parameters.AddWithValue("@p4", LastName);

//Cmd.Parameters.AddWithValue("@p5", Password);

//Cmd.Parameters.AddWithValue("@p6", ConformPassword);

//Cmd.Parameters.AddWithValue("@p7", Address);

//Cmd.Parameters.AddWithValue("@p8", State);

//Cmd.Parameters.AddWithValue("@p9", City);

Cmd.ExecuteNonQuery();

Con.Close();

GridView1.EditIndex = -1;

GetData();

}

 

 I am getting this error Hoe to solve please tell me argent

 

Object reference not set to an instance of an object. in this line

 

String S = "Update Registration set UserName='" + UserName.Text + "',FirstName='" + FirstName.Text + "',LastName='" + LastName.Text + "',Password='" + Password.Text + "',ConformPassword='" + ConformPassword.Text + "',Address='" + Address.Text + "',State='" + State.SelectedItem + "',City='" + City.SelectedItem + "' where EmailAddress='" + EmailAddress + "'";