adonetaccess.aspx.cs

ASP C#代码实例 适合初学人士学习使用

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Data.OleDb;
using System.Configuration;

namespace Example_11_16
{
	/// <summary>
	/// Summary description for ADONETAccess.
	/// </summary>
	public class ADONETAccess : System.Web.UI.Page
	{
		protected System.Web.UI.WebControls.DataGrid datagrid;
		protected System.Web.UI.WebControls.Button btnAddPet;
		private readonly string OLEDBCONNECTIONSTRING = ConfigurationSettings.AppSettings["OLEDBCONNECTIONSTRING"].ToString();
	
		private void Page_Load(object sender, System.EventArgs e)
		{
			if (!IsPostBack)  ReadRecords();
		}
		private void ReadRecords()
		{
			OleDbConnection conn = null;
			OleDbDataReader reader = null;
			try
			{
				conn = new OleDbConnection(OLEDBCONNECTIONSTRING + Server.MapPath("Datas.mdb"));
				conn.Open();

				OleDbCommand cmd = 
					new OleDbCommand("Select * FROM DataTable", conn);
				reader = cmd.ExecuteReader();

				datagrid.DataSource = reader;
				datagrid.DataBind();
			}
			catch (Exception e)
			{
				Response.Write(e.Message);
				Response.End();
			}
			finally
			{
				if (reader != null)  reader.Close();
				if (conn != null)  conn.Close();
			}
		}

		private void btnAddPet_Click(object sender, System.EventArgs e)
		{
			string sql = "INSERT INTO DataTable (Name, Type)"
				+ " VALUES (\"new\", \"new\")";
			ExecuteNonQuery(sql);
			ReadRecords();
		}

		private void ExecuteNonQuery(string sql)
		{
			OleDbConnection conn = null;
			try
			{
				conn = new OleDbConnection(OLEDBCONNECTIONSTRING + Server.MapPath("Datas.mdb"));
				conn.Open();

				OleDbCommand cmd = 
					new OleDbCommand(sql, conn);
				cmd.ExecuteNonQuery();
			}
			catch (Exception e)
			{
				Response.Write(e.Message);
				Response.End();
			}
			finally
			{
				if (conn != null)  conn.Close();
			}
		}

		private void datagrid_CancelCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
		{
			datagrid.EditItemIndex = -1;
			ReadRecords();	
		}
		private void datagrid_EditCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
		{
			datagrid.EditItemIndex = e.Item.ItemIndex;
			ReadRecords();
		}
		private void datagrid_DeleteCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
		{
			int ID = (int) datagrid.DataKeys[(int) e.Item.ItemIndex];

			string sql = "DELETE FROM DataTable WHERE ID=" + ID;
			ExecuteNonQuery(sql);
			ReadRecords();
		}

		private void datagrid_UpdateCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
		{
			int ID = (int) datagrid.DataKeys[(int) e.Item.ItemIndex];

			string name = ((TextBox)e.Item.Cells[1].Controls[0]).Text;
			string type = ((TextBox)e.Item.Cells[2].Controls[0]).Text;

			string sql = 
				"UPDATE DataTable SET Name=\"" + name + 
				"\", Type=\"" + type + "\"" +
				" WHERE ID=" + ID;
			ExecuteNonQuery(sql);

			datagrid.EditItemIndex = -1;
			ReadRecords();
		}

		#region Web Form Designer generated code
		override protected void OnInit(EventArgs e)
		{
			//
			// CODEGEN: This call is required by the ASP.NET Web Form Designer.
			//
			InitializeComponent();
			base.OnInit(e);
		}
		
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{    
			this.datagrid.CancelCommand += new System.Web.UI.WebControls.DataGridCommandEventHandler(this.datagrid_CancelCommand);
			this.datagrid.EditCommand += new System.Web.UI.WebControls.DataGridCommandEventHandler(this.datagrid_EditCommand);
			this.datagrid.UpdateCommand += new System.Web.UI.WebControls.DataGridCommandEventHandler(this.datagrid_UpdateCommand);
			this.datagrid.DeleteCommand += new System.Web.UI.WebControls.DataGridCommandEventHandler(this.datagrid_DeleteCommand);
			this.btnAddPet.Click += new System.EventHandler(this.btnAddPet_Click);
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion
	}
}