如何修复更新按钮即使单击也不起作用

Question

我有正在运行的更新查询，但是我不知道现在更改了什么，它不起作用，只是弹出了消息框消息，但是代码更新不适用于数据库。

 private void btnUpdate_Click(object sender, EventArgs e)
    {
        var database = DBConnection.DBConnect();
        SqlCommand cmd = new SqlCommand("dbo.Customer_update", database);
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.Parameters.Add("@Id",SqlDbType.Int).Value = txtId.Text;
        cmd.Parameters.Add("@Firstname", SqlDbType.NVarChar).Value = txtFirstName.Text;
        cmd.Parameters.Add("@Lastname", SqlDbType.NVarChar).Value = txtLastName.Text;
        cmd.Parameters.Add("@City", SqlDbType.NVarChar).Value = txtCity.Text;
        cmd.Parameters.Add("@Country", SqlDbType.NVarChar).Value = txtCountry.Text;
        cmd.Parameters.Add("@Phone", SqlDbType.NVarChar).Value = txtPhone.Text;
        SqlDataAdapter adapter = new SqlDataAdapter(cmd);
        DataTable ds = new DataTable();
        adapter.Fill(ds);
        ShowCustomers();
        MessageBox.Show("Succeccfully updated into DataBase");           
    }       

这是存储过程

ALTER procedure [dbo].[Customer_update] 
( @Id int null ,
@Firstname nvarchar(40)=null,
@Lastname nvarchar(40)=null,
@City nvarchar(40)=null,
@Country nvarchar(40)=null,
@Phone nvarchar(20)=null
)
as 
begin 
update Customer 
set FirstName=@FirstName,
LastName=@Lastname,
City=@City,
Country=@Country,
Phone=@Phone
where Id=@Id 
end