EditStaff got input string problem

Question

i got the error message: Input string was not in a correct format. I cannot find the error.

 

 

string staffId = null;

SqlConnection conn = null;

SqlCommand cmd = null;

string connectionString = null;

protected void btnSubmit_Click(object sender, EventArgs e)

{

connectionString = ConfigurationManager.ConnectionStrings["FacilityCS"].ConnectionString;

conn = new SqlConnection(connectionString);

string sql = "UPDATE Staff SET StaffId=@staffId, Password=@password, StaffName=@staffName,";

sql+=" Email=@email, PhoneNo=@phoneNo, Title=@title, Role=@role";

try

{

cmd = new SqlCommand(sql, conn);

cmd.Parameters.AddWithValue("@staffId", tbStaffId.Text);

cmd.Parameters.AddWithValue("@password", tbPassword.Text);

cmd.Parameters.AddWithValue("@staffName", tbStaffName.Text);

cmd.Parameters.AddWithValue("@email", tbEmail.Text);

cmd.Parameters.AddWithValue("@phoneNo", tbPhoneNo.Text);

cmd.Parameters.AddWithValue("@title", Convert.ToInt32(ddlTitle.SelectedValue));

cmd.Parameters.AddWithValue("@role", Convert.ToInt32(rbRole.SelectedValue));

conn.Open();

int row = cmd.ExecuteNonQuery();

if(row>0)

{

lblOutput.Text = "Record Updated successfully";

}

}

catch(Exception ex)

{

lblOutput.Text = "Error Message: " + ex.Message;

}

finally

{

if (conn != null)

conn.Close();

}

}