using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
using System.IO;

public partial class singerInfoChange : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            db_singer();
        }
    }
    public void db_singer()
    {
        SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["LocalSqlServer"].ToString());
        try
        {
            string sqlselect = "SELECT * FROM [singer]";

            SqlCommand cmd = new SqlCommand(sqlselect, conn);
            SqlDataAdapter da = new SqlDataAdapter();
            da.SelectCommand = cmd;
            SqlCommandBuilder sqlcb = new SqlCommandBuilder(da);
            DataTable dt = new DataTable();

            da.Fill(dt);
            if (dt.Rows.Count > 0)
            {
                dg.DataSource = dt;
                dg.DataBind();
            }
            else
            {
                msg.Text = "暂时还没有添加任何歌手！";
                dg.Visible = false;
            }
            //弹出是否删除框
            for (int i = 0; i < this.dg.Items.Count; i++)
            {
                this.dg.Items[i].Cells[1].Attributes.Add("onclick", "return confirm('确定删除该记录？')");
            }
        }
        catch (Exception ex)
        {
            msg.Text = ex.Message.ToString();
        }
        finally
        {
            conn.Close();
        }
    }
    protected void dg_DeleteCommand(object source, DataGridCommandEventArgs e)
    {
        SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["LocalSqlServer"].ToString());
        string singer_name = dg.DataKeys[e.Item.ItemIndex].ToString();
        conn.Open();
        SqlTransaction myTrans = conn.BeginTransaction();
        try
        {
            SqlCommand cmd = new SqlCommand();
            cmd.Transaction = myTrans;
            cmd.CommandText = "delete from [singer] where singer=@singer";
            cmd.Connection = conn;
            cmd.Parameters.Add("@singer", SqlDbType.NChar).Value = dg.DataKeys[e.Item.ItemIndex].ToString();
            cmd.ExecuteNonQuery();

            cmd.CommandText = "select * from [music] where singer = @singer";
            string musicpath = "";
            SqlDataReader dr =cmd.ExecuteReader();
            while (dr.Read())
            {
                musicpath = new DirectoryInfo(Server.MapPath("")).FullName.ToString() + @"\file\" + dr.GetString(1).Trim().ToString();
                File.Delete(musicpath);
            }
            dr.Close();

            cmd.CommandText = "delete from [music] where singer =@singer";
            cmd.ExecuteNonQuery();

            cmd.CommandText = "delete from [album] where singer =@singer";
            cmd.ExecuteNonQuery();
           
            myTrans.Commit();

            db_singer();
        }
        catch (Exception ex)
        {
            msg.Text = ex.ToString();
            myTrans.Rollback();
        }
        finally
        {
            conn.Close();
        }
    }
    protected void dg_PageIndexChanged(object source, DataGridPageChangedEventArgs e)
    {
        dg.CurrentPageIndex = e.NewPageIndex;
        db_singer();
    }
}